No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Association of IOP with Systemic Factors in a Korean Cohort
Abstract
Purpose:
To assess the relationship of intraocular pressure (IOP) to age, sex, and other demographic and health characteristics in a Korean cohort.
Methods:
This retrospective cross-sectional study included subjects (n = 155,198) without glaucoma. All participants underwent health screening at the Kangbuk Samsung Hospital from August 2012 to July 2013. Anthropometric measurements, systemic health characteristics, and ocular examination including noncontact tonometry were performed on all participants. Additionally, sociodemographic and behavioral questionnaires were obtained. The systemic variables were analyzed by multiple regression analysis to identify their relationship with IOP.
Results:
The mean IOP tended to be highest in subjects in their 50s and lowest in subjects in their 20s and 60s for both Korean men and women. This pattern remained the same after adjusting for several demographic and health characteristics. The mean IOP for men was significantly higher than that for women (p < 0.001), but the difference between sexes decreased with increasing age. In the univariate analysis, almost all systemic factors showed a positive association with IOP except for high-density lipoprotein cholesterol. By multiple regression analysis, IOP was positively associated with sex (male), current smoking status, systolic blood pressure, fasting plasma glucose, body mass index, total cholesterol, and high-density lipoprotein (p ≤ 0.001).
Conclusions:
In a Korean cohort, the mean IOP was highest in subjects in their 50s. The mean IOP for men was significantly higher than that for women. Several systemic factors were significantly correlated with IOP.
... A number of previous studies had investigated the association between intraocular pressure and cigarette smoking. Positive association had been postulated, which showed higher intraocular pressure among smokers in Western population (5,7,8) and Asian population (9,10), yet there are few such studies in Southeast Asia and none in Malaysia. Additionally, the population-based study conducted in Asia used noncontact tonometer, which might be less precise than the Goldmann applanation tonometer (9). ...
... The IOP value for healthy young adult in this study is within the normal value of 10-21 mmHg (6). Aging caused distribution of IOP tend to be lowest in their 20s and 60s, by which it increases when one reaching their 50s and decreases as reaching their 60s, according to one retrospective cross-sectional study on Korean population (10). Healthy young adult was chosen to eliminate the influence of age-and systemic-related problems on intraocular pressure, whereby this study documented a younger age group of smokers compared to previous study. ...
... In this study, young smokers were reported to have higher IOP on both eyes as compared to that of non-smokers. This result is in accordance with previous population-based studies done on Western (7,8) and Asian population (9,10) although it contradicts a few cross sectional studies (8,(10)(11). ...
Introduction: Nicotine administration can cause changes to the aqueous humour resistance, which could influence the intraocular pressure (IOP). This preliminary study is designed to determine the difference and association of IOP in a sample of young adult smokers and non-smokers in Selangor. Methods: Healthy young adult males between 18 and 35 years old who are non-alcoholic and without ocular and systemic diseases were recruited in this study. Smokers were classified into light smokers, moderate smokers, and heavy smokers based on the smoking index. The IOP was measured using Goldmann applanation tonometer on each eye .Results: The analysis involved a total of 34 young adult males (mean age: 23.29 ± 2.19 years), with 17 (50%) smokers and 17 (50%) non-smokers. For smokers, the median IOP value was statistically higher (16.00 (1.8) mmHg), than non-smokers (11.70 (1.0) mmHg) (p <0.001). All smokers were found to be light smokers; light smokers SI 0-50 and light smokers SI 51-100 showed no significant difference on IOP. Spearman’s correlation indicates a moderate positive correlation between the IOP of both eyes to the smoking index, with rs= 0.46 (p = 0.006) Conclusion: This study exemplified a higher IOP among smokers and moderate positive association of smoking index to the IOP among healthy young adults, even for those with a brief history of smoking.
Keywords: : Intraocular pressure, Smokers, Light smokers, Smoking index
... In addition to age and sex, previous studies have also investigated the presence of associations between IOP and the body mass index (BMI), hypertension, and abnormal lipid profile parameters [15][16][17][18]. The Beaver Dam Eye Study showed that reduced IOP is linked to lower systemic blood pressure [19]. ...
... On the other hand, Stewart et al. have found that increased levels of total cholesterol and high-density lipoprotein (HDL) are not associated with an increase in IOP [22]. These studies provide controversial and conflicting evidence on the association between hypertension, age, sex, and hyperlipidemia with IOP [15]. To the best of our knowledge, studies that address the effect of systemic health parameters on IOP have not been conducted in the western region of Saudi Arabia. ...
Background
A normal intraocular pressure (IOP) is essential for maintaining the normal structure and function of the eyes. Furthermore, an elevated IOP is a known risk factor for glaucoma. As the results from studies addressing the relationship between IOP and systemic health parameters are conflicting, researchers have not reached a consensus. This study aimed to evaluate the relationship between IOP and health parameters among non-glaucomatous participants in the western region of Saudi Arabia.
Method
We retrospectively reviewed the medical records of 255 participants aged 20 years and above who had not received any medical treatment for ocular hypertension or glaucoma at King Abdulaziz University Hospital (KAUH), Jeddah, Saudi Arabia, from January 2019 to April 2021. The patients were categorized into age groups, divided by decades (ranging from 20-29 years to 80+ years); the most prevalent age group was 60-69 years. The data were entered using Microsoft Excel 2016 (Microsoft Corporation, Redmond, Washington), and Statistical Package for the Social Sciences (SPSS) software was used for univariate analysis. The relationship between continuous variables was analyzed by the Pearson correlation coefficient. The differences between continuous and categorical variables were assessed by the t-test and one-way analysis of variance (ANOVA) test, respectively.
Results
The mean (standard deviation) IOP in the right and the left eyes was 15.7 mmHg (4.0) and 15.6 mmHg (3.9), respectively. There were no significant associations between IOP and lipid profile parameters (p > 0.05). There was a statistically significant difference in the right IOP, in relation to the age groups (p = 0.006). Moreover, the mean IOP in the left eye was significantly higher among patients with diabetes than in the patients without diabetes (p = 0.007) as well as in patients with hypertension than in the patients without hypertension (p = 0.023).
Conclusion
The effect of total cholesterol, triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), BMI, and sex on IOP could not be established in our study. However, over the past years, people's diets have incorporated higher cholesterol and fat content, leading to higher BMI levels. Therefore, further studies of the association between BMI and IOP are critical to determine if BMI is certainly a significant risk factor for increased IOP and glaucoma.
... Studies have reported different results on the association between IOP and sex: some studies have reported a higher IOP in women than in men [9,10,18,19], and others have reported opposite results [5,[20][21][22][23]. Based on the KNHANES from 2009-2010, the mean IOP was significantly higher in men than in women and the higher IOP was also significantly correlated with male gender after multivariate analysis [21]. ...
... Based on the KNHANES from 2009-2010, the mean IOP was significantly higher in men than in women and the higher IOP was also significantly correlated with male gender after multivariate analysis [21]. Another study that used a large-scale database of Korean subjects (n = 155,198) also reported the same trend [20]. These studies may account for the higher IOP level in men (19 mmHg) compared with the level for women (18 mmHg) in the present study. ...
Objectives
To investigate significant intraocular pressure (IOP) levels associated with the risk of open-angle glaucoma (OAG) in the treatment-naïve Korean population.
Methods
Participants ≥20 years of age in Korea National Health and Nutrition Examination Survey 2010–2011 were divided into two groups, those with higher and lower IOP values, compared with the reference IOP value. We compared the risk of OAG in each group using regression analyses. The IOP value that yielded the highest statistical significance was determined as an IOP significantly associated with the OAG risk.
Results
A total of 7,650 participants (7,292 control, 358 OAG) were included. The mean IOP was significantly higher in OAG group (14.4 ± 2.9 mmHg), compared to control group (13.9 ± 2.7 mmHg, P = 0.022). In association with an increased risk of OAG, the significant IOP value was 18 mmHg (Odds ratio [OR] = 1.79, 95% confidence interval [CI] 1.14–2.80, P = 0.011). Additionally, sex-difference was identified and they were 19 mmHg (OR = 2.79, 95% CI 1.27–6.16, P = 0.011) in men and 18 mmHg (OR = 2.65, 95% CI 1.32–5.33, P = 0.006) in women. The IOP values associated with significantly decreased risk of glaucoma were determined to be 14 mmHg in men (OR = 0.68, 95% CI 0.47–0.99, P = 0.042) and 16 mmHg in women (OR = 0.47, 95% CI 0.27–0.81, P = 0.007).
Conclusions
In consideration of the risk to benefit ratio, the reference IOP level for screening or setting the target IOP for treatment could be considered different from traditional 21 mmHg in Korean population.
... The exclusion criteria were as follows: missing data on PA and eye examination (n = 855 and n = 209, respectively), conditions that affect PA including chronic disease (stroke, chronic renal failure, and depression), restrictions in the ability to engage in PA (dementia, fracture, etc.), and nutritional issues. We evaluated without filtering outliers since defining the normal range of IOP might lead to selection bias, although the average IOP is 14.91 mmHg [20,21]. Thus, 8343 participants in the KNHANES 2008-2012 were eligible for this study. ...
Adequate exercise is essential for maintaining a healthy lifestyle and preventing ageing-related diseases. The purpose of this study was to assess the associations between exercise and glaucoma, as well as exercise and intraocular pressure (IOP) levels. This study used data from the Korea National Health and Nutrition Examination Surveys 2008–2012, which in total included 10,243 men aged ≥40 years. The presence of glaucoma and the higher IOP of each eye (IOPmax) taken from the health examination survey and the ophthalmic examination were used for analyses. A questionnaire was used to assess exercise activity, which was analysed regarding intensity, frequency, and duration. Regression analyses were used to determine the relationships of exercise parameters with the odds of glaucoma and IOPmax. The prevalence of glaucoma was significantly lower in men who engaged in moderate-to-vigorous intensity exercise compared to those who did not exercise (p = 0.012). The odds for glaucoma were the lowest in men engaged in vigorous intensity exercise (p = 0.009). However, IOPmax was highest in the vigorous intensity exercise group (p = 0.026) with no linear trend pattern. These results suggest that exercise decreased the odds of glaucoma via several factors including non-IOP mechanisms.
... p < 0.0001) [86]. Another retrospective study showed a positive correlation between serum HDL-C levels and IOP elevation (Coefficient β (SE) = 0.002 (0.001), p-value = 0.001) [87]. Fair comparison of these studies with one another is challenging because of differences in study design, the confounding factors included in the analysis, and the population characteristics among studies. ...
There is limited understanding of the specific role of high-density lipoprotein cholesterol (HDL-C) in the development of various age-related ocular diseases, despite it being a common measurable biomarker in lipid profiles. This literature review summarizes current knowledge of the role of HDL-C, if any, in pathogenesis and progression of four age-related ocular diseases, namely age-related macular degeneration (AMD), age-related cataract, glaucoma, and diabetic retinopathy (DR), and will primarily discuss epidemiological and genetic evidence.
... P=0.47) is indicative of the absence of bias in the studies included in the meta-analysis for T6 (s=12); however, the Egger's test has low power for meta-analyses containing small to moderate numbers of studies (43). IOP can be affected by a number of factors (e.g., age, gender, blood pressure, BMI, total cholesterol, low-density lipoprotein, high-density lipoprotein, blood glucose, diabetes, smoking) (76). Although the researchers conducting each study included in the meta-analysis attempted to control for factors other than the effect of Trendelenburg position on IOP, it is possible that the increase in IOP was affected by factors other than patient position. ...
... Previous studies reported that a number of cardiovascular and metabolic factors were associated with IOP fluctuation and glaucoma development in POAG. 10,[32][33][34] Our study found that diabetes mellitus was associated with smaller IOP fluctuation, whereas smoking was associated with greater IOP fluctuation in PACG eyes. In our current sample, we also observed that patients with diabetes mellitus tended to have higher mean IOP in general, but less IOP fluctuation. ...
Purpose:
To determine the demographic, ocular, and systemic factors associated with long-term intraocular pressure (IOP) fluctuation in primary angle closure disease (PACD).
Methods:
This prospective cohort study included 422 PACD eyes from 269 Chinese patients, including 274 primary angle closure glaucoma (PACG) eyes and 152 primary angle closure / primary angle closure suspect (PAC/PACS) eyes. Long-term IOP fluctuation defined as the standard deviation of all IOP measurements over 2 years (at least 5 measurements in total). Chinese patients with PACD were recruited and followed up three-monthly. Eyes with IOP-lowering surgery or lens extraction performed within the 2-year study period were excluded. Patient demographics, received treatments, ocular biometry, retinal nerve fiber layer thickness, and systemic factors (e.g. hypertension, smoking) were evaluated. Generalized estimating equations adjusting for inter-eye correlation were used to determine the associations.
Results:
Eyes with PACG had significantly higher IOP fluctuation than PAC/PACS (2.4±1.2▒mm Hg versus 2.1±0.9▒mm Hg, P=0.04). In the multivariate analysis with PACG eyes, higher baseline IOP (P<0.001), greater number of IOP-lowering medications (P<0.001), previous trabeculectomy (P=0.002), and current smoking (P=0.03) were significantly associated with larger IOP fluctuation, while diabetes mellitus was associated with lower IOP fluctuation (P=0.03). Among PAC/PACS eyes, younger age group (P<0.001), male gender (P=0.002), and higher baseline IOP (P<0.001) were significantly associated with larger IOP fluctuation.
Conclusions:
PACG eyes have greater IOP fluctuation than PAC/PACS eyes. Certain demographic, ocular, and systemic factors are associated with IOP fluctuation in PACD eyes.
Aims
To investigate the physiological nyctohemeral intraocular pressure (IOP) rhythms of normal Chinese adults using a novel contact lens sensor system (CLS) that can output IOP in millimetres of mercury (mm Hg) continuously.
Methods
Fifty-nine eyes of 59 normal Chinese adults completed 24-hour IOP monitoring using the novel CLS. A descriptive analysis was conducted on the 24-hour IOP mean, peak and acrophase, trough and bathyphase, fluctuation, and mean amplitude of intraocular pressure excursion (MAPE). The continuous data were analysed at several periods (diurnal period, 08:00–20:00 hours; nocturnal period, 22:00–06:00 hours; sleep time, 0:00–06:00 hours), and compared between right and left eyes, males and females, and different age ranges (<30, and ≥30), respectively.
Results
Normal adults had a lower peak, higher trough, smaller fluctuation and smaller MAPE (p<0.05 for all comparisons) but non-significantly different mean (p=0.695) in the nocturnal period or sleep time compared with the diurnal period. The 24-hour IOP peak and trough showed the frequency of occurrence ranging from 1.69% to 15.25% at an interval of 2 hours. No IOP parameter showed significant difference between right and left eyes (p>0.1 for all comparisons). The male group had larger 24-hour and diurnal IOP fluctuation and MAPE (p<0.05 for all comparisons). Subjects aged 30 or over had higher 24-hour and diurnal mean, higher peak, and larger MAPE (p<0.05 for all comparisons).
Conclusion
Continuous 24-hour IOP output from the CLS in normal Chinese was stable with a comparable mean level between day and night, as well as scattered acrophase and bathyphase. The 24-hour IOP mean increased with age, and IOP variations were positively correlated to age and male sex.
Purpose
To investigate the immediate short-term effects of smoking in habitual smokers, on the tear film, pupil size and accommodative ability of the human eye.
Methods
Habitual smokers were tested within 5 min of smoking a cigarette. The tear film analysis was undertaken using tear break–up time (TBUT), tear lipid layer thickness and tears meniscus height (TMH) measurements. Three different ways of tear break–up time (TBUT) were used; using fluorescein; a non-invasive TBUT using tearscope; and a video captured method with a corneal topographer. Pupil size was measured objectively using the video capture on the corneal topographer. Accommodative ability was checked by performing a ‘push up test' to measure amplitudes of accommodation (AoA) and by measuring defocus curves.
Results
Forty-five participants were enrolled (mean age 22.0 ± 4.4 years). TBUT was reduced after smoking a cigarette with all three assessment methods and this reduction was statistically significant (p < 0.001). A reduction in lipid layer thickness was seen after smoking a cigarette with both methods used and was statistically significant (p < 0.01). A significant reduction in pupil size (p < 0.01) and in AoA (p < 0.001) was observed after smoking a cigarette. The difference in TMH and defocus curves, before and after smoking, were not statistically significant (p > 0.05).
Conclusion
The study shows that there is an immediate adverse effect of smoking on TBUT and AoA which seems to be very transient.
Aims: To investigate the association between plasma homocysteine levels and glaucomatous retinal nerve fiber layer (RNFL) defect in South Korean population.
Materials and methods: This retrospective cross-sectional study included subjects who underwent screening at Kangbuk Samsung Hospital Health Screening Center between August 2012 and July 2013. Subjects underwent physical examination and provided samples for laboratory analysis of homocysteine. Subjects were divided equally into four quartiles (Qs) based on plasma homocysteine level. Digital fundus photographs of both eyes were obtained. Determination of glaucomatous disc appearance was based on criteria set forth by the International Society of Geographical and Epidemiological Ophthalmology and based on the appearance of the RNFL and optic disc. Multivariate logistic regression models were used to define elevated glaucoma risk with P < 0.2 on univariate analysis.
Results: A total of 78,049 subjects were included; 76,093 subjects were male, and 1956 subjects were female. When analyzed by gender, the mean homocysteine level in the male group with glaucomatous RNFL defects (11.05 ± 3.80 µmol/L) was higher than those without RNFL defects (10.81 ± 4.12 µmol/L (P = 0.000, χ² test). Upon multifactorial logistic regression analysis adjusted for age, gender, creatinine, diabetes mellitus, hypertension, and hyperlipidemia, glaucomatous RNFL defects had a significant correlation with plasma homocysteine level. Based on the Q2 level, the odds ratio (OR) of Q3 was 1.267, while the OR of Q4 was 1.285 (95% CI = 1.067−1.505, 1.081−1.529, respectively, P for trend = 0.001).
Conclusion: Our results suggest that homocysteine level is associated with the presence of glaucomatous RNFL defects.
Purpose:
To evaluate the relationship between intraocular pressure (IOP) and various anthropometric measures.
Design:
A population-based cross-sectional study.
Methods:
A total of 5008 participants, 2080 men and 2928 women ≥19 years of age were included from the Korea National Health and Nutrition Examination Survey V database, focusing on the years 2010 and 2011. We selected IOP in the right eye of a normal healthy population as the outcome variable of our study. We analyzed the relationship between IOP and anthropometric parameters using dual-energy X-ray absorptiometry by sex. Lean body mass was calculated as total body mass minus fat mass. We used general linear models and logistic regression analysis to evaluate risk factors of high IOP. Our main outcome measure was correlation between anthropometric data and IOP.
Results:
In multivariate general linear models, greater body mass index (BMI) and waist circumference were correlated with higher IOP for both men (BMI, β = 0.053, P = .026; waist circumference, β = 0.016, P = .067) and women (BMI, β = 0.074, P < .001; waist circumference, β = 0.028, P < .001). Greater fat mass (β = 0.027, P = .037) and fat mass/lean body mass (β = 1.170, P = .06) were correlated with higher IOP, while greater lean body mass/weight (β = -3.188, P = .025), lean body mass/BMI (β = -1.379, P = .002), appendicular skeletal muscle mass/BMI (β = -2.270, P = .022), and bone mineral content/BMI (β = -11.653, P = .031) were correlated with lower IOP in women, but not in men (P > .10).
Conclusions:
In healthy women, greater fat mass was associated with higher IOP, and greater muscle mass was associated with lower IOP after adjusting for weight and BMI. Fat and muscle influenced IOP in women independently.
Purpose:
Whether or which blood heavy metal levels (BHMLs) influence elevating intraocular pressure (IOP) are unknown. We examined the relationship among blood lead, mercury, and cadmium levels, blood pressure (BP), and IOP and assessed whether BP mediates these BHMLs-IOP associations.
Methods:
We analyzed data on 8371 adult (≥20 years) from the Korea National Health and Nutrition Examination Survey from 2008 to 2012. Mediation analysis was used to examine the contribution of BP to the BHMLs-IOP relationship.
Results:
IOP and three BHMLs were significantly associated with systolic and diastolic BP. But IOP was associated with only blood lead and mercury levels. BP significantly mediated lead-IOP and mercury-IOP associations: BP accounted for 20.5% and 14.2% of the association with IOP. Blood lead and mercury levels were significantly associated with IOP.
Conclusions:
BP significantly mediates the effects of those blood lead and mercury levels on IOP outcome. Prospective studies are needed to further examine the causal pathway from BHMLs to IOP elevation.
This review describes a scheme for diagnosis of glaucoma in population based prevalence surveys. Cases are diagnosed on the grounds of both structural and functional evidence of glaucomatous optic neuropathy. The scheme also makes provision for diagnosing glaucoma in eyes with severe visual loss where formal field testing is impractical, and for blind eyes in which the optic disc cannot be seen because of media opacities.
Objective
Elevated intraocular pressure (IOP) contributes to the progression of visual defects such as glaucoma. This study determined whether metabolic syndrome (MetS) and cardiovascular risk factors are associated with IOP in South Korean men.Methods
We analyzed data on 4875 men who participated in the Korean National Health and Nutrition Examination Survey 2008-2010. We recorded the values for age, weight, height, body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), insulin, homeostasis model assessment of estimated insulin resistance (HOMA-IR), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), non-HDL-C (NHDL-C), and TG/HDL-C, as well as sociodemographic factors. IOP was measured using Goldmann applanation tonometry.ResultsWeight, BMI, WC, SBP, DBP, FBG, insulin, HOMA-IR, TC, LDL-C, TG, NHDL-C, TG/HDL-C, and the prevalence of MetS differed significantly among the three groups with IOP (P<0.05). Mean IOP was higher in subjects who were obese and had hypertension, diabetes mellitus, MetS, abdominal obesity, high TG, high FBG, or high BP compared with normal subjects (P<0.005). Analysis using Pearson's correlation coefficient showed that all cardiometabolic risk factors were significantly associated with IOP (P<0.005), with the exception of WC and HDL-C. A multivariate linear regression analysis showed that IOP was positively correlated with BMI, SBP, DBP, FBG, HOMA-IR, TC, LDL-C, TG, NHDL-C, and TG/HDL-C after adjusting for all covariates (all P<0.05).Conclusions
Cardiometabolic risk factors, including the components of MetS, are associated with increased IOP.Eye advance online publication, 7 March 2014; doi:10.1038/eye.2014.43.
Aim:
To evaluate the relationship between intraocular pressure (IOP) and systemic health parameters such as age, gender, body mass index (BMI), total cholesterol, high density lipoprotein (HDL), and triglyceride (TG) in a Korean population.
Materials and Methods:
A total of 30,893 healthy subjects underwent automated multiphasic tests, including non-contact tonometry, automated perimetry, fundus photography, and blood samplings for total cholesterol, HDL, and TG. Seven age groups were divided by decades ranging from 20 to 29 years to 80 + years. The association between IOP and BMI, plasma lipid profiles was examined using cross-sectional analysis.
Results:
The mean age of subjects was 47.7 years. The mean IOP of subjects was 15.4 ± 3.2 mmHg for both eyes. The mean IOP of men was significantly higher than women (P = 0.000). By multiple linear regression analysis, IOP was positively associated with gender (male), BMI, total cholesterol, and TG and negatively associated with age (P = 0.000). BMI, total cholesterol, and TG had significantly positive correlations with IOP after adjusting for age, gender, and other variables which can influence the IOP (P = 0.000).
Conclusions:
In a Korean population, the mean IOP, total cholesterol, TG, and BMI values of men were higher than women. IOP was found to increase with total cholesterol, TG, BMI, and to decrease with only age regardless of sex.
The current study was performed to assess the distribution of intraocular pressure (IOP) and its association with metabolic syndrome (MS) in a community.
We measured IOP and MS components from 446 adults, age 20 or more years old, who reside in a community in Kyunggi Province, South Korea. We compared the level of IOP according to the number of metabolic abnormalities and between normal and abnormal metabolic components. Linear regression analyses were used to determine the relationship between IOP and metabolic components.
No significant difference in IOP (mean +/- SE) was found between men (12.24 +/- 2.42) and women (12.55 +/- 2.41 mmHg, p > 0.1), while IOP of men tended to decrease as age increased (p for trend < 0.01). After adjusting for age, IOP of subjects with abdominal obesity in men and high blood pressure in women were significantly higher than those without abdominal obesity or high blood pressure (p < 0.05). Female subjects with MS showed significantly higher IOP than those without MS. Participants with more metabolic disturbances tended to have a greater IOP elevation with a linear trend after adjusting for age and sex. In the univariate regression analysis, age and waist circumference were significantly associated with IOP in men, but systolic and diastolic blood pressure were associated with IOP in women. In final multiple regression model, age, systolic blood pressure, and triglyceride were associated with IOP in women, and age in men.
These findings suggest that MS and its components may be important determinants of elevated IOP.
The intraocular and systemic blood pressure, height, weight, and haemoglobin were measured in 573 subjects over 60 years old from a general practice population. Intraocular pressure was positively and independently related to systemic blood pressure (P less than 0.0001) and obesity (P less than 0.01) as assessed by the ponderal index. Systolic pressure rather than diastolic or mean pressure was most closely correlated with intraocular pressure and it is suggested that the systolic head of pressure increases the filtrated fraction of aqueous humour to cause a small but sustained rise in intraocular pressure. It is also suggested that obesity may decrease the facility of aqueous outflow.
The Beaver Dam Eye Study is a population-based study of age-related eye diseases in persons 43-86 yr of age. Applanation tonometry was done on all study subjects. Mean intraocular pressure (IOP) increased significantly with age. Mean IOP differed little between the sexes and was not significantly different after age adjustment (in right eyes of 2721 women, it was 15.5 mm Hg, and in right eyes of 2135 men, it was 15.3 mm Hg). There was an association of IOP with systolic and diastolic blood pressures, body mass index, hematocrit, serum glucose, glycohemoglobin, cholesterol level, pulse, nuclear sclerosis, season, and time of day of measurement. These data confirm that, in a general population, IOP is associated with important systemic and ocular characteristics. Those characteristics should be considered in further research on determinants of IOP.
Primary open-angle glaucoma (POAG) is one of the leading causes of blindness in the United States and worldwide. Three to 6 million people in the United States are at increased risk for developing POAG because of elevated intraocular pressure (IOP), or ocular hypertension. There is no consensus on the efficacy of medical treatment in delaying or preventing the onset of POAG in individuals with elevated IOP. Therefore, we designed a randomized clinical trial, the Ocular Hypertension Treatment Study.
To determine the safety and efficacy of topical ocular hypotensive medication in delaying or preventing the onset of POAG.
A total of 1636 participants with no evidence of glaucomatous damage, aged 40 to 80 years, and with an IOP between 24 mm Hg and 32 mm Hg in one eye and between 21 mm Hg and 32 mm Hg in the other eye were randomized to either observation or treatment with commercially available topical ocular hypotensive medication. The goal in the medication group was to reduce the IOP by 20% or more and to reach an IOP of 24 mm Hg or less.
The primary outcome was the development of reproducible visual field abnormality or reproducible optic disc deterioration attributed to POAG. Abnormalities were determined by masked certified readers at the reading centers, and attribution to POAG was decided by the masked Endpoint Committee.
During the course of the study, the mean +/- SD reduction in IOP in the medication group was 22.5% +/- 9.9%. The IOP declined by 4.0% +/- 11.6% in the observation group. At 60 months, the cumulative probability of developing POAG was 4.4% in the medication group and 9.5% in the observation group (hazard ratio, 0.40; 95% confidence interval, 0.27-0.59; P<.0001). There was little evidence of increased systemic or ocular risk associated with ocular hypotensive medication.
Topical ocular hypotensive medication was effective in delaying or preventing the onset of POAG in individuals with elevated IOP. Although this does not imply that all patients with borderline or elevated IOP should receive medication, clinicians should consider initiating treatment for individuals with ocular hypertension who are at moderate or high risk for developing POAG.
To evaluate the effect of hormone replacement therapy on climacteric ocular complaints, lacrimal secretion, intraocular pressure (IOP), and corneal thickness.
A prospective, controlled, randomized study on 50 healthy women (mean age 53.4 +/- 3.8 years) at least 1 year after spontaneous menopause. Twenty-five women (group A) were treated with transdermal 17beta-estradiol (50 microg/day) and medroxyprogesterone acetate (10 mg/day) for 12 days per cycle. Twenty-five untreated women (group B) were used as a control group. All participants underwent eye examination at the beginning of the study and after 3 and 6 months of therapy to detect ocular diseases and to measure lachrymal secretion, IOP, and corneal thickness.
No significant differences were observed between the two groups at the beginning of the study. After 3 and 6 months of treatment, we observed a significant reduction in the percentage of women in group A affected by ocular symptoms and in the severity of symptomatology in comparison with baseline and with group B (P < 0.01). A significant increase of both basal and stimulated lachrymal secretion was observed after 3 months of therapy in group A in comparison with baseline (P < 0.01). There was a significant decrease of IOP (P < 0.01) after 3 months of therapy in group A (P < 0.01), and a slight, nonsignificant increase of corneal thickness was observed in group A at 3 and 6 months in comparison with basal values.
Our data suggest that hormone replacement therapy may exert a beneficial effect on ocular symptomatology, increase lachrymal secretion, reduce IOP, and increase corneal thickness.
Objective:
To review the effect of smoking on common ocular disorders.
Data sources:
Medline literature search, 1966 to 1999.
Study selection:
The following key words were used: smoking; Graves' disease, age-related macular degeneration; glaucoma; cataract.
Data extraction:
Epidemiological and experimental studies were reviewed.
Data synthesis:
Cigarette smoking is an important risk factor for cardiovascular, respiratory, and malignant diseases. There is also a strong association between smoking and a number of common eye diseases, which include Graves' ophthalmopathy, age-related macular degeneration, glaucoma, and cataract. Despite the multifactorial aetiology of these ocular syndromes, smoking is an independent risk factor that has dose-response effects. It causes morphological and functional changes to the lens and retina due to its atherosclerotic and thrombotic effects on the ocular capillaries. Smoking also enhances the generation of free radicals and decreases the levels of antioxidants in the blood circulation, aqueous humour, and ocular tissue. Thus, the eyes are more at risk of having free-radical and oxidation attacks in smokers.
Conclusion:
Smoking, if continued, may perpetuate further ocular damage and lead to permanent blindness. Cessation of smoking and avoidance of passive smoking is advised to minimise the harmful effects of smoking on the eyes.
Objective:
To provide data on the distribution of intraocular pressure (IOP) in a predominantly black population, which has a high prevalence of open-angle glaucoma.Design:
Population-based prevalence study.Setting and Participants:
Participants (N=4601) (age range, 40-84 years) who had undergone applanation tonometry measurements in the Barbados Eye Study. Self-reported race was 93% black, 4% mixed (black and white), and 3% white or other.Data Collection:
A standardized protocol included applanation tonometry and other ocular measurements, fundus photography, demographic data, and an interview.Main Outcome Measures:
The average of 3 IOP measurements at the Barbados Eye Study visit was used to compare IOP by self-reported race. Descriptive data on IOP by age, sex, glaucoma status, and cup-disc ratio were examined in the black population.Results:
The IOP was highest in the population of African origin. The mean (±SD) IOP values for black, mixed, and white participants were 18.7±5.2, 18.2±3.8, and 16.5±3.0 mm Hg, respectively. An IOP greater than 21 mm Hg was present in 18.4%, 13.6%, and 4.6% of the black, mixed, and white participants, respectively. In analyses that were adjusted for age, sex, and glaucoma status, such values were 5 times as likely in black than white participants and 3.5 times as likely in mixed race participants (P<.01). Among the black participants, the mean IOP increased approximately 1 mm Hg for every increase in 10 years of age. After excluding persons with any type of glaucoma, suspected glaucoma, or a history of glaucoma treatment, women had significantly (P<.01) higher IOP values; however, no significant IOP trends by sex were evident in the group with glaucoma. The IOP was also positively associated (P<.05) with vertical cup-disc ratios. After 2 visits, the IOP remained 21 mm Hg or less in 21% of the persons with glaucoma vs 64% of those without glaucoma.Conclusions:
In the black participants, the IOP was higher than in the white participants. The IOP was also associated with age and cup-disc ratios. The results showed that open-angle glaucoma and a high IOP alone have a different distribution by sex; although open-angle glaucoma was more frequent in men, ocular hypertension was more frequent in women. These data have implications for the detection and causation of open-angle glaucoma in this high-risk population.
Objective:
The influence of lipids on blood and plasma viscosity has not been fully elucidated. In this study we evaluated the contribution of HDL cholesterol to blood and plasma viscosity, in healthy subjects.
Methods:
One hundred and forty-four (80 males and 64 females) subjects were enrolled among free-living participants to a cardiovascular disease screening. Exclusion criteria were: diabetes, elevated triglycerides, elevated LDL cholesterol, smoking and drug use. Blood lipids were measured by routine methods. Blood and plasma viscosity were measured by a cone-plate viscometer (Wells-Brookfield DV-III, Stoughton, U.S.A.). Subjects were divided in two groups: at low (<50 mg/dl) and high HDL cholesterol (>50 mg/dl).
Results:
Blood and plasma viscosity were similar in subjects at low and high HDL cholesterol. In univariate analysis none of the lipid variables was significantly correlated with blood and/or plasma viscosity. In multivariate analysis only LDL cholesterol was marginally associated with blood viscosity.
Conclusion:
HDL cholesterol does not influence blood and plasma viscosity in healthy normolipidemic subjects. LDL cholesterol is marginally associated with blood viscosity.
Objective
To provide the results of the Early Manifest Glaucoma Trial, which compared the effect of immediately lowering the intraocular pressure (IOP), vs no treatment or later treatment, on the progression of newly detected open-angle glaucoma.
Design
Randomized clinical trial.
Participants
Two hundred fifty-five patients aged 50 to 80 years (median, 68 years) with early glaucoma, visual field defects (median mean deviation, −4 dB), and a median IOP of 20 mm Hg, mainly identified through a population screening. Patients with an IOP greater than 30 mm Hg or advanced visual field loss were ineligible.
Interventions
Patients were randomized to either laser trabeculoplasty plus topical betaxolol hydrochloride (n = 129) or no initial treatment (n = 126). Study visits included Humphrey Full Threshold 30-2 visual field tests and tonometry every 3 months, and optic disc photography every 6 months. Decisions regarding treatment were made jointly with the patient when progression occurred and thereafter.
Main Outcome Measures
Glaucoma progression was defined by specific visual field and optic disc outcomes. Criteria for perimetric progression were computer based and defined as the same 3 or more test point locations showing significant deterioration from baseline in glaucoma change probability maps from 3 consecutive tests. Optic disc progression was determined by masked graders using flicker chronoscopy plus side-by-side photogradings.
Results
After a median follow-up period of 6 years (range, 51-102 months), retention was excellent, with only 6 patients lost to follow-up for reasons other than death. On average, treatment reduced the IOP by 5.1 mm Hg or 25%, a reduction maintained throughout follow-up. Progression was less frequent in the treatment group (58/129; 45%) than in controls (78/126; 62%) (P =.007) and occurred significantly later in treated patients. Treatment effects were also evident when stratifying patients by median IOP, mean deviation, and age as well as exfoliation status. Although patients reported few systemic or ocular conditions, increases in clinical nuclear lens opacity gradings were associated with treatment (P = .002).
Conclusions
The Early Manifest Glaucoma Trial is the first adequately powered randomized trial with an untreated control arm to evaluate the effects of IOP reduction in patients with open-angle glaucoma who have elevated and normal IOP. Its intent-to-treat analysis showed considerable beneficial effects of treatment that significantly delayed progression. Whereas progression varied across patient categories, treatment effects were present in both older and younger patients, high- and normal-tension glaucoma, and eyes with less and greater visual field loss.
• Subcutaneous wound-tissue oxygen (Psqo2) tension in eight volunteers fell rapidly and significantly in response to smoking, and remained low for 30 to 50 minutes. Sham "smoking" had no effect. These data suggest that a typical "pack-per-day" smoker experiences tissue hypoxia during a significant portion of each day. The degree of hypoxia found in these subjects has been associated with poor wound healing in animal and human studies. The onset and duration of tissue hypoxia paralleled the well-established plasma pharmacokinetics of nicotine. This suggests that peripheral vasoconstriction, induced by the adrenergic effects of nicotine, may contribute to the observed decrease in Psqo2.
(Arch Surg. 1991;126:1131-1134)
Objectives:
To clarify whether smoking was associated with elevated intraocular pressure (IOP) and to evaluate the interrelationship among IOP, blood viscosity, and smoking.
Methods:
This cross-sectional study analyzed health examination data obtained between 2001 and 2004 from 1113 individuals (829 men and 284 women), ranging in age from 28 to 79 years, who had not undergone any ocular surgery or medical treatment for hypertension, ocular hypertension, and glaucoma.
Results:
Multiple-regression analysis showed that systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), and number of cigarettes smoked per day had a significantly positive association with IOP in men (P < 0.05). In women also, SBP, DBP, and BMI were positively related to IOP (P < 0.05). On the contrary, age had a significant negative association with IOP in both sexes (P < 0.01). Analysis of covariance and multiple logistic regression analyses showed that the adjusted mean IOP and the multivariate odds ratios for IOP increased with increasing cigarette consumption in men (P for trend = 0.01 and 0.06, respectively). Analysis of covariance found that smoking was significantly associated with both high IOP and high hematocrit in men (P for trend <0.05); however, the adjusted mean IOP values were higher in smokers than in nonsmokers, regardless of the hematocrit level.
Conclusions:
The results of this study suggested that the IOP level may be substantially affected by smoking habit in middle-aged and older Japanese men.
Objective
To describe the distribution and associations of demographic, familial, medical, and ocular factors with intraocular pressure (IOP).
Methods
A cluster stratified random sample of urban and rural residents of Victoria, Australia, aged 40 years and older. Participants completed an interview and underwent a standardized dilated ophthalmic examination including measurement of IOP with an electronic applanation tonometer (Tono-Pen). Glaucoma status(possible, probable, definite) was determined by a consensus panel. The main outcome measure was IOP.
Results
The mean age of the 4576 participants was 59 years, 53% were women, 32% were born overseas, and 132 had open-angle glaucoma. Geometric mean (SD) IOP was 14.3 (±1.5) mm Hg. The relationship between IOP and nuclear sclerosis, iris color, and family history of glaucoma depended on glaucoma status. In those with glaucoma, family history of glaucoma and country of birth were significantly associated with IOP in multivariate models (model: r2 = 0.08, P = .01). In the group without glaucoma, place of residence, use of alcohol, iris color, vitamin E intake, and spherical equivalent were associated with IOP (model: r2 = 0.01, P = .006).
Conclusion
In participants with glaucoma, genetic factors seem to be stronger predictors of IOP, whereas in those without glaucoma, lifestyle and physiological factors seem to play a greater role.
To investigate the distribution of intraocular pressure (IOP) and its associated factors in a large Korean population based on the data from the nationwide cross-sectional survey.
We obtained 2009-2010 data from the Korea National Health and Nutrition Examination Survey (KNHANES) (n = 17 901). After excluding individuals under 19 years of age, a total of 13 431 subjects were enrolled. All participants completed a comprehensive questionnaire and underwent an ocular examination including measurement of IOP by Goldmann applanation tonometry, as well as a systemic evaluation including blood pressure measurements, anthropometry and blood tests.
The mean IOP in the right eye was 13.99 ± 2.75 mmHg, and in the left eye, 13.99 ± 2.75 mmHg, representing no significant bilateral difference. There was, however, a significant difference between males (14.19 ± 2.78 mmHg) and females (13.79 ± 2.70 mmHg) (p < 0.001). Multiple regression analysis revealed that higher IOP was significantly correlated with male sex, higher myopic refractive error, higher body mass index, higher systolic blood pressure, higher fasting plasma glucose and higher total cholesterol (all p < 0.05). On the other hand, age, histories of smoking or migraine or cold hands/feet were not significantly correlated with IOP (all p > 0.05).
In the general Korean population, IOP increases with male sex and increasing myopia. Further, IOP is significantly correlated with systemic factors relating to cardiovascular disease and metabolic syndrome.
Background and aim:
The relationship between hyperlipidemia and blood and plasma viscosity is not completely clear. While increasing viscosity is often reported with increasing blood lipids, lipid-lowering treatments are often unable to normalize the viscosity values. Aim of this study is to try to clarify the relationship between blood lipids and viscosity.
Methods and results:
Apparently healthy subjects were enrolled (n = 410). Smokers, diabetics, obese, and hypertriglyceridemic (above 400 mg/dl) were excluded. Blood (at shear rate 225/s) and plasma viscosity were measured at 37°C. Erythrocyte rigidity (Tk) was calculated according to Dintenfass. Blood lipids and glucose were measured by routine methods. Hyperlipidemic subjects (n = 315) had higher values of plasma viscosity (1.44 ± 0.13 vs. 1.40 ± 0.12 cP, p = 0.007), and blood viscosity (4.51 ± 0.54 vs. 4.35 ± 0.55 cP, p = 0.013), compared to normolipidemic subjects (n = 95). In simple correlation analysis, plasma viscosity was directly associated with LDL cholesterol, and inversely with Tk and HDL cholesterol. In multiple regression analysis the association with LDL and HDL was strengthened, though these two variables as a whole accounted for only 5% (adjusted R2) of the variability of plasma viscosity. Blood viscosity was significantly associated with haematocrit, plasma viscosity, Tk and all considered variables but age in simple correlation analysis, but only with haematocrit, plasma viscosity and Tk in multiple regression analysis.
Conclusions:
LDL cholesterol and HDL cholesterol influence plasma viscosity, but not blood viscosity. Triglycerides up to values of 400 mg/dl do not seem to have important effects, at least in apparently healthy subjects and at the shear rates used in the present study. The contribution of LDL and HDL cholesterol to plasma viscosity seems however quite limited.
Objective:
This study aimed to investigate the association between intraocular pressure and metabolic syndrome according to menopause status in nonglaucomatous Korean women.
Methods:
We examined the relationship between intraocular pressure and metabolic syndrome in 4,524 nonglaucomatous Korean women (2,866 premenopausal women and 1,658 postmenopausal women) who participated in the 2008 Korean National Health and Nutrition Examination Survey. Multivariate linear regression analysis was used to assess the relationship between metabolic syndrome and intraocular pressure after adjusting for age, body mass index, smoking status, alcohol consumption, regular exercise, hypertension medication, and diabetes medication according to menopause status in women.
Results:
The prevalence of metabolic syndrome was 5.4% for premenopausal women and 28.0% for postmenopausal women. The mean intraocular pressure gradually increased in accordance with the increasing number of components for metabolic syndrome in postmenopausal women (P = 0.002), but not in premenopausal women (P = 0.387). In multivariate regression analysis, intraocular pressure was significantly associated with metabolic syndrome in postmenopausal women (P = 0.015) after adjusting for confounding variables, but not in premenopausal women (P = 0.940).
Conclusions:
Intraocular pressure was associated with metabolic syndrome in postmenopausal women, but not in premenopausal women. These findings suggest that intraocular pressure changes may be linked to metabolic syndrome in postmenopausal women.
Background Mean intraocular pressure in postmenopausal women is higher than that in menstruating women. Intraocular pressure is positively correlated with systemic blood pressure. No previous study has compared intraocular pressure in postmenopausal women with systemic hypertension and those without.
Purpose To investigate the effects of menopause on intraocular pressure in subjects with and without high blood pressure, after eliminating those factors that can affect intraocular pressure.
Methods Normotensive menstruating and menopausal, along with hypertensive menopausal subjects of the same age groups were studied. Intraocular pressure was measured with the Goldmann applanation tonometer.
Results The mean intraocular pressure of the normotensive and hypertensive postmenopausal women were 0.73 ≥ 0.27 ( p < 0.05). and 1.09 ≥ 0.34 ( p < 0.01) mmHg higher than normotensive menstruating women respectively. The mean intraocular pressure of hypertensive postmenopausal women was 0.36 ≥ 0.15 mmHg ( p < 0.05) higher than that of normotensive postmenopausal women.
Conclusions Menopause significantly increases intraocular pressure. Mean intraocular pressure of hypertensive postmenopausal women was significantly ( p < 0.05) higher than that of normotensive postmenopausal women. Knowledge of the normal level of intraocular pressure during various stages of female sexual life may help glaucoma screeners.
To evaluate the intraocular pressure (IOP) distribution and its regional association in the South Korean population.
Cross-sectional, epidemiologic study.
All participants underwent interview and the following ocular examinations: visual acuity measurement, autorefraction, pachymetry, anterior segment evaluation, slit-lamp examination, Goldmann applanation tonometry, binocular optic disc evaluation, fundus photography, and visual field test. Patients with ocular diseases other than mild senile cataract or with history of ocular surgery were excluded.
A total of 3191 subjects residing in urban and rural areas were recruited. Mean IOP of patients from the urban area was significantly higher than that of those from the rural area (14.45 ± 2.67 mm Hg vs 13.53 ± 2.76 mm Hg, P < .05). There was regional difference of mean IOP, even after controlling for different demographic factors in the 2 areas (P < .05). Average IOP in the right eye of the investigated sample of South Korean population was 14.10 ± 2.74 mm Hg. Multiple regression analysis showed positive correlation between mean IOP and central corneal thickness, vertical cup-to-disc ratio, history of hypertension, smoking, and female sex, whereas IOP tended to decrease by approximately 0.2 mm Hg when age increased by 10 years.
This is the first population-based epidemiologic study measuring IOP in the South Korean population. Mean IOP of the urban area was found to be significantly higher than the corresponding value of the rural area. Therefore, the regional difference, as well as other various factors, has to be considered in epidemiologic study of the distribution of IOP.
To examine the distribution of intraocular pressure (IOP) and its related systemic and ocular biometric factors in a population-based study in a southwestern island of Japan.
Cross-sectional, population-based study.
All residents of Kumejima Island, Japan, located in southwestern Japan (eastern longitude, 126 degrees 48 minutes and northern latitude 26 degrees 20 minutes), 40 years of age and older were asked to undergo a comprehensive questionnaire and ocular examination, including measurement of IOP with Goldmann applanation tonometry.
Of the 4632 eligible residents, 3762 (81.2%) underwent the examination. In 2838 non-glaucomatous subjects from whom reliable measurements of IOP were obtained, the mean IOPs +/- standard deviation in all, men, and women were 15.1 +/- 3.1 mm Hg (n = 2838), 15.2 +/- 3.1 mm Hg (n = 1450), and 15.1 +/- 3.0 mm Hg (n = 1388), respectively, with no significant intersex difference (P = .63). Multivariate regression analysis demonstrated that higher IOP was significantly correlated with younger age (P < .001), higher body mass index (P < .001), higher systolic blood pressure (P < .001), history of diabetes mellitus (P = .001), thicker central corneal thickness (P < .001), steeper corneal curvature (P < .001), and longer axial length (P < .018), but not with anterior chamber depth and the Shaffer angle width grade.
Younger age, higher body mass index, higher systolic blood pressure, diabetes, thicker central corneal thickness, and steeper corneal curvature were significantly correlated with higher IOP. The present results confirm that IOP is associated with systemic and ocular biometric factors and may define specific subgroups most likely to have an elevated IOP.
This study aimed to investigate the association of intraocular pressure (IOP) with the metabolic syndrome and other emerging cardiometabolic risk factors.
A total of 1112 participants undergoing a health check-up in a community hospital were recruited. All participants underwent ophthalmological examination including IOP measurement.
Participants with metabolic syndrome had significantly higher IOP than those without metabolic syndrome (mean IOP+/-SD: 15.07+/-2.74 vs 14.29+/-2.72 mm Hg, P=2x10(-4)). Each additional component of the metabolic syndrome was associated with a mean increase in IOP of 0.33 mm Hg (95% confidence interval: 0.18-0.48, trend P<0.0001). Other insulin resistance-related features, including hepatic steatosis, increased left ventricular mass, and proteinuria, were also associated with IOP (P<0.0001, 0.002, and 0.01, respectively). However, we did not find significant association of plasma apolipoprotein A, apolipoprotein B1, homocysteine, or highly sensitive C-reactive protein levels with IOP. IOP was also not associated with measures of subclinical atherosclerosis including brachial-ankle pulse wave velocity, ankle-brachial index, and vertebral artery flow.
Metabolic syndrome and other insulin resistance-related features, including hepatic steatosis, increased left ventricular mass, and proteinuria, are strongly associated with IOP.
To describe the distribution of intraocular pressure (IOP) and its cross-sectional relationship to age, systolic blood pressure (sBP), and central corneal thickness (CCT) in an Asian population.
This was a population-based, cross-sectional study of 3280 Malay subjects (78.7% response) aged 40 to 80 years residing in Singapore. The participants had a standardized interview, examination, and ocular imaging at a centralized study clinic. IOP was measured with Goldmann applanation tonometry (GAT) before pupil dilation, CCT measurements were obtained with an ultrasound pachymeters, and sBP was taken with participants seated after 5 minutes of rest with an automatic blood pressure monitor.
IOP increased with age to the sixth decade, after which a decrease in IOP was seen with further increase in age, resulting in an inverted U pattern. sBP increased linearly with age whereas CCT decreased linearly with age. In regression models, age, CCT, and sBP were all significant determinants of IOP (P < 0.001 for all three). In younger persons aged 40 to 59 years, both CCT and sBP were positively associated with IOP (P < 0.001 for both), but in older persons of 60 to 80 years, only age and sBP had a positive association with of IOP (P = 0.001 for age, P < 0.001 for sBP).
Age, CCT and sBP are significant determinants of IOP in persons aged 40 to 80 years, with CCT being a more important determinant in younger persons. The opposing effects of age-specific changes in sBP and CCT interact to lead to a relatively flat profile of IOP with age, possibly with a subtle inverted U-shaped relationship.
To evaluate the epidemiologic evidence for a causal association between tobacco smoking and primary open angle glaucoma (POAG).
Systematic review, including quality assessment, of published analytical epidemiologic studies and evaluation of the evidence using established causality criteria (strength, consistency, temporality, dose response, reversibility, and biologic plausibility).
Eleven papers describing 9 case-control studies, 1 prospective cohort study, and a paper describing a pooled analysis based on 2 prospective cohort studies were included in the review. The methodologic quality of most included studies was poor. The strongest studies methodologically were the cohort studies on which the pooled analysis was based. Neither the prospective cohort study (rate ratio not reported) nor the pooled analysis of 2 prospective cohort studies (adjusted rate ratio 0.9) found an association between smoking and POAG. There was a significant positive association between smoking and POAG in only 2 of the case-control studies (adjusted odds ratio 2.9 and 10.8). There was no evidence of a dose-response relationship with smoking or of reversibility of effect in the studies where this was assessed.
This systematic review provided little evidence for a causal association between smoking and development of POAG. Given the limited evidence from high quality studies, and the possibility that flaws in many of the studies reviewed biased the results toward the null, further high quality research to confirm our conclusions is needed. However, it remains important to warn ophthalmic patients of the dangers of smoking and provide cessation support owing to the clear evidence of links between smoking and other ocular and systemic diseases.
As intraocular pressure (IOP) and age are consistent risk factors of glaucoma, it is of special interest to know the association between IOP and possibly relating factors including age in Japan where a high prevalence of normal-tension glaucoma has been reported. The aim of this report was to evaluate the distribution of and factors related to applanation IOP in a population-based study in Japan.
A randomly sampled group of 3021 residents (response rate 78.1%) of Tajimi City, aged 40 years or older, underwent screening examinations including measurements of IOP with Goldmann applanation tonometry and central corneal thickness.
Among right eyes without glaucoma, suspected glaucoma or other disorders which could affect correct IOP measurements, IOP averaged 14.6 (SD 2.7) and 14.5 (2.5) mm Hg in men and women, respectively, with no significant intergender difference (p = 0.342). Multiple regression analyses revealed that age was significantly negatively correlated with IOP (non-standardised beta (B) = -0.020/year, p = 0.0001). Higher body mass index (B = 0.14/BMI, p<0.0001), higher mean blood pressure (B = 0.022/mm Hg, p<0.0001), history of diabetes (p = 0.0019), thicker cornea (B = 0.014/microm, p<0.0001), higher myopia (B = 0.055/dioptres, p = 0.0043) and steeper corneal curvature (B = -0.72/mm, p = 0.0002) were also significantly correlated with higher IOP.
In an adult Japanese population, applanation IOP averaged 14.5 mm Hg and was negatively correlated with age after adjusting for other related factors. A positive correlation between IOP and myopia was found.
Specimens from 17 human eyes, ranging in age from 3 to 80 years, were subjected to morphometric studies using light microscope, transmission electron microscope and scanning electron microscope, in order to clarify the age-related changes in the normal trabecular tissue. Statistical analyses showed that the cellularity in the various regions of the trabecular meshwork significantly declined with age. The spaces corresponding to the aqueous outflow pathway in each region of the meshwork also significantly decreased with age. On the other hand, extracellular materials significantly increased in amount with age in all regions of the trabecular meshwork. However, the decrease in the cellularity and the outflow pathway spaces did not show any statistically significant regional difference. These results suggest that general narrowing of the outflow pathway spaces due to the accumulation of extracellular materials with age is the cause of the increase in aqueous outflow resistance with age, and that each region of the trabecular meshwork is equally responsible for the increased resistance.
Using computer-filed data for approximately 187,000 eyes of 94,000 Japanese subjects who underwent automated multiphasic tests, we studied the mean and the upper limit of intraocular pressure by stratifying the whole sample by age, systolic blood pressure, and degree of obesity. Intraocular pressure increased when systolic blood pressure or obesity increased and intraocular pressure decreased with advancing age when systolic blood pressure and the degree of obesity were kept constant. Apparent disparities in the upper limit of intraocular pressure were noted between the "obese and hypertensive" and "lean and hypotensive" groups, who were at the highest and the lowest extremes, respectively. Stratified normal intraocular pressure is a standard specifically applied for different sex, age, or other systemic conditions; however, the values for the group with the highest intraocular pressure should eventually be modified by the data for Western populations.
Intraocular pressure (IOP) was measured in a mixed population of 12,803 apparently healthy employed people. Mean IOP was 13.5 +/- 3.3 mmHg, without sex difference. Frequency distribution demonstrated skewness towards high values. IOP weakly correlated with age (R = 0.06), and older subgroups showed more marked skewness, but further analysis showed this effect to be spurious. The correlations of IOP with heart rate and with systolic blood pressure were small, but stronger than with age (R = .16 and .15, respectively). Moreover, when corrected for heart rate, the effect of age was nullified. Other factors found to be correlated with IOP included blood glucose and hemoglobin concentration, smoking, and height. None of these factors significantly increased the correlation between IOP and heart rate or blood pressure, and the skewness was not fully explained by any of these factors or their combinations. The value of the epidemiologic approach to detection of factors responsible for ocular hypertension is stressed.
Statistical analysis of intraocular pressure was conducted on approximately 200,000 healthy subjects who were examined at the Aichi Prefectural Center of Health Care in Nagoya, Japan, during the last decade. The IOP was estimated with either Schl øtz or noncontact tonometers, which consistently showed a decreasing tendency of IOP with age in both sexes. Multivariate analysis on systemic values disclosed that obesity, systolic BP, and age were the most influential factors of IOP. Stratification of the sample by systolic BP, obesity index, and age indicated that young, obese, and hypertensive subjects had the highest IOP, while old, lean, and hypotensive subjects showed the lowest IOP. It was confirmed that the IOP is physiologically maintained by a counterbalance between the IOP-lowering effect of age and the IOP-raising effects of obesity and systolic hypertension, which are largely age dependent.
The rate of aqueous formation was measured with fluorophotometry in a group of 113 normal human subjects who ranged in age from 20 to 83 years. A slight decrease in the rate of aqueous humor formation with aging was detected, but the rate was remarkably stable. The rate of aqueous humor formation was more stable than intraocular pressure or anterior chamber volume in this group and more stable than the tonographic C value reported by other investigators.
The purpose of this study is to investigate the association of primary open-angle glaucoma (POAG), intraocular pressure (IOP), and systemic blood pressure.
Subjects participating in the Rotterdam Study (n = 4187, 55 years of age and older) were examined according to standard protocols, including a medical history interview, IOP measurement, perimetry, funduscopy, and blood pressure measurement. Primary open-angle glaucoma was defined by the presence of a glaucomatous visual field defect. Additionally, the distinction was made between high-tension glaucoma, defined as POAG with an IOP of more than 21 mmHg, and normal-tension glaucoma, defined as POAG with an IOP of 21 mmHg or less. The relation between blood pressure and hypertension with IOP, POAG, high-tension glaucoma, and normal-tension glaucoma was studied by means of regression analysis.
A systolic blood pressure or diastolic blood pressure that was 10 mmHg higher was associated with an IOP that was, on average, 0.23 mmHg (95% confidence interval [CI], 0.19-0.27) or 0.24 mmHg (95% CI, 0.16-0.32) higher, respectively. The presence of hypertension was associated with a higher mean IOP of 0.66 mmHg (95% CI, 0.39-0.93). A higher systolic blood pressure of 10 mmHg was associated with an odds ratio of 1.22 (95% CI, 1.03-1.46) for high-tension glaucoma and 0.90 (95% CI, 0.72-1.12) for normal-tension glaucoma. Hypertension was associated with an odds ratio of 2.33 (95% CI, 0.99-5.47) for high-tension glaucoma and 0.77 (95% CI, 0.22-2.72) for normal-tension glaucoma.
Systemic blood pressure and hypertension are associated with IOP and high-tension glaucoma. No association was found between blood pressure or hypertension and normal-tension glaucoma.
To evaluate a possible association of glaucoma with alcohol ingestion and cigarette-smoking behavior.
A population-based survey was performed of persons 43 to 84 years of age in Beaver Dam, Wisconsin (n = 4926). The diagnosis of glaucoma was based on visual field testing, measurement of intraocular pressure, and cup-to-disc ratios based on detailed protocols for examination, measurement, and gradings of photographs. Alcohol intake and smoking history were based on questionnaire responses. The prevalence of glaucoma in "heavy drinkers," whether current or past, was contrasted with the prevalence in those not reporting heavy drinking. Prevalences in never, past, and current smokers were compared.
There was no difference in frequency of glaucoma by drinking status. Similarly, there was no difference in the frequency of glaucoma by cigarette-smoking status.
In these prevalence data, neither heavy drinking nor cigarette-smoking behavior was related to the prevalence of open-angle glaucoma. This finding may reflect a real absence of a pathologic effect.
Because the protean biological effects of ethanol include acute alterations in both cortical function and circulatory control, we investigated the effect of acute alcohol consumption on retrobulbar hemodynamics and contrast sensitivity in healthy human volunteers.
Twelve young adults received orange juice with and without ethanol in a double-masked fashion. The ethanol dose was sufficient to raise blood alcohol to 0.07 +/- 0.003 g/dl. Retrobulbar hemodynamics were assessed at baseline and twice at elevated blood alcohol by color Doppler imaging.
Acute elevation of blood alcohol lowered intraocular pressure from 13.0 +/- 0.7 to 10.7 +/- 0.7 mm Hg (p < 0.05). In contrast, elevated blood alcohol left peak systolic velocity, end-diastolic velocity and the resistance index constant in three retrobulbar arteries (ophthalmic, central retinal and posterior ciliary). For example, in the central retinal artery, peak systolic velocity, end-diastolic velocity and the resistance index averaged 11.0 +/- 1.3 cm/s, 2.8 +/- 0.4 cm/s and 0.75 +/- 0.03 before ethanol, as compared with 10.5 +/- 1.0 cm/s, 2.9 +/- 0.3 cm/s and 0.72 +/- 0.03 after ethanol (all p = NS). Alcohol ingestion also failed to alter either visual acuity or contrast sensitivity, as assessed under both photopic and mesopic conditions.
Although ethanol has widespread cognitive and cardiovascular effects, at blood levels near legal definitions of intoxication we found it ineffective in altering either retrobulbar hemodynamics or contrast sensitivity.
This case-control study evaluated risk factors for open-angle glaucoma (OAG) and high intraocular pressure (IOP), including systemic hypertension and its treatment, other systemic factors, familial, and demographic variables. The three study groups were based on masked ophthalmologic gradings of visual fields and fundus photographs, as well as tonometry. The OAG group (n = 122) had OAG field defects, IOP > 21 mmHG, and cup-disc ratios > or = 0.5 and/or evidence of glaucoma disc damage. The ocular hypertensives (n = 108) had no field defects, IOP > 21 mmHg and normal discs. The controls (n = 190) had no field defects, IOP < 21 mmHg and normal discs. The data collection protocol included a standardized interview and measurements. Medical history was confirmed by contacting the primary care physicians (89% response from physicians). Study groups were compared by polychotomous logistic regression analyses. Men were more likely to have OAG and less likely to have ocular hypertension. Systemic hypertension was more frequent in ocular hypertensives (Odds Ratio = 2.36); high diastolic pressure was associated with OAG and ocular hypertension (OR = 2.13 and 2.21, respectively). Treatment for systemic hypertension was unrelated to OAG risk. Low perfusion pressures (blood pressure-IOP differences) were strongly associated with OAG and ocular hypertension, a finding that could be due to the high IOP in these groups. A family history of glaucoma was more frequent in OAG (OR = 3.08) and ocular hypertension (OR = 2.38) than in controls. Alcohol consumption was related to ocular hypertension (OR = 2.32). No other associations were significant. The results confirm an association of blood pressure with intraocular pressure. Since the OAG and ocular hypertensive groups had similar blood pressure results, an independent effect of blood pressure on OAG was not substantiated.
To evaluate the demographic, medical, ocular, familial, and other factors possibly associated with intraocular pressure (IOP) in a black population, after excluding persons with any type of glaucoma.
The Barbados Eye Study was a population-based study of a random sample of residents of Barbados, West Indies, aged 40 to 84 years.
A subset of the Barbados Eye Study population consisting of 3752 black Barbados Eye Study participants without glaucoma.
A standardized protocol included applanation tonometry and other ocular data, blood pressure measurements, anthropometry, complexion pigmentation gradings, and a comprehensive interview.
Intraocular pressure was based on the average of 3 measurements at the Barbados Eye Study visit. Multiple linear regression was used to evaluate factors associated with IOP.
Systolic blood pressure (or hypertension), diabetes history, and age were the major factors positively associated with IOP (P<.01). Other positively related factors were female gender, darker complexion, pulse rate, higher body mass, seasonality, family history of glaucoma, current alcohol use, and current smoking. These factors explained 10% of the variation in IOP.
By identifying risk factors, these results define specific subgroups most likely to have an elevated IOP. The high IOP in this population may be linked to the high prevalence of hypertension and diabetes. Aside from age and a family history of glaucoma, none of the risk factors for high IOP evaluated in this study was similar to those associated with open-angle glaucoma.
Tobacco smoke is composed of as many as 4,000 active compounds, most of them toxic on either acute or long-term exposure. Many of them are also poisonous to ocular tissues, affecting the eye mainly through ischemic or oxidative mechanisms. The list of ophthalmologic disorders associated with cigarette smoking continues to grow. Most chronic ocular diseases, with the possible exception of diabetic retinopathy and primary open-angle glaucoma, appear to be associated with smoking. Both cataract development and age-related macular degeneration, the leading causes of severe visual impairment and blindness, are directly accelerated by smoking. Other common ocular disorders, such as retinal ischemia, anterior ischemic optic neuropathy, and Graves ophthalmopathy, are also significantly linked to this harmful habit. Tobacco smoking is the direct cause of tobacco-alcohol amblyopia, a once common but now rare disease characterized by severe visual loss, which is probably a result of toxic optic nerve damage. Cigarette smoking is highly irritating to the conjunctival mucosa, also affecting the eyes of nonsmokers by passive exposure (secondhand smoking). The dangerous effects of smoking are transmitted through the placenta, and offspring of smoking mothers are prone to develop strabismus. Efforts should be directed toward augmenting the campaign against tobacco smoking by adding the increased risk of blindness to the better-known arguments against smoking. We should urge our patients to quit smoking, and we must make them keenly aware of the afflictions that can develop when smoke gets in our eyes.
To assess the influence of aging, blood pressure, and body mass index (BMI) on intraocular pressure (IOP) in a large Japanese population.
Cross-sectional and longitudinal study.
The participants in this study were 69,643 Japanese men and women 20 to 79 years of age. They were office workers and their family members who had received annual health examinations from 1989 to 1997. The records of the participants who received health examinations were reviewed retrospectively. Each participant was examined according to a standard protocol, including tonometry with a noncontact tonometer, anthropometric measurements, and blood pressure measurements. The data from the subjects' most recent visit were analyzed cross-sectionally. The data from the 68,998 men and women of the total participants who were born between the 1920s and 1960s were used in longitudinal analysis.
Tonometric and anthropometric measurements.
Mean values of IOP, systolic blood pressure, diastolic blood pressure, and BMI were determined. The relationship among IOP, age, systolic blood pressure, diastolic blood pressure, and BMI was studied using the multiple linear regression model with cross-sectional analysis. In longitudinal analysis, regression coefficients of IOP against age, systolic blood pressure, diastolic blood pressure, and BMI were calculated using the mixed effect model.
The mean (+/-standard deviation) IOP values for men and women were 11.9+/-2.5 and 11.5+/-2.4 mmHg, respectively. In cross-sectional analysis, IOP decreased significantly with age (P < 0.001). However, longitudinal analysis showed that IOP increased significantly with age in both men and women (P < 0.001). Systolic blood pressure and BMI were positively correlated to IOP in both the cross-sectional and longitudinal studies.
The authors found an inconsistency in the change in IOP against age between cross-sectional and longitudinal analysis. It is suspected that birth cohort differences in ocular characteristics influence IOP in the Japanese population.
Some cross-sectional studies have suggested that age, systolic blood pressure and obesity are positively related to intraocular pressure (IOP), but few longitudinal studies have examined this relationship. This study was carried out to evaluate the association between intraocular pressure and obesity by cross-sectional and longitudinal analyses in a large Japanese population.
Data were collected from annual health examinations between 1989 and 1997 and reviewed retrospectively. Subjects of the cross-sectional analysis were 70 139 males and females aged 14-94 years. Among these subjects, 25 216 males and females who had undergone IOP measurements more than three times were analysed longitudinally. The association between IOP and obesity was examined cross-sectionally and longitudinally.
Cross-sectional analysis: The mean IOP at the last visit was 11.6 mmHg. The IOP decreased gradually with age and was significantly higher in males than in females in almost all age groups. Body mass index (BMI) significantly correlated with IOP after controlling for age, gender and blood pressure. Longitudinal analysis: There was a significant association between longitudinal change in IOP and change in weight. This relationship remained significant after controlling for initial BMI, initial blood pressure, change in blood pressure, gender and age.
This study showed a significant association between IOP and obesity in both cross-sectional and longitudinal analysis. These findings suggest that obesity is an independent risk factor for increase in IOP.
This study aimed to assess the influence of age on intraocular pressure(IOP) in a general population. The Blue Mountains Eye Study assessed 3654 residents aged 49+ years during 1992-1994. Intraocular pressure was measured using Goldmann applanation tonometry. Subjects with glaucoma, those currently on glaucoma medications and those with a history of cataract surgery were excluded. The IOP was reliably measured in 3260 subjects. Mean IOP was 16.0 mmHg with no significant difference found between men and women (P < 0.89). In univariate analyses, age was positively associated with IOP (P < 0.05). Systolic blood pressure (SBP) was strongly positively associated with IOP (P < 0.001). After adjusting for SBP, there was a trend for IOP to decrease with increasing age(P < 0.051). After further adjusting for other potential confounders (diabetes, glaucoma family history and myopia), age was no longer significantly associated with intraocular pressure (P < 0.29). In summary,no evidence was found of an independent age affect on IOP.
This study aimed to evaluate the relationship between intraocular pressure (IOP) and age and obesity, adjusted for systemic health parameters such as sex and mean blood pressure, in a Korean population.
A total of 13 212 healthy participants underwent automated multiphasic tests, including tonometry, automated perimetry, fundus photography, blood pressure and body mass index (BMI). Six age groups were used, divided by decades ranging from 20-29 years to 70+ years. The association between IOP and systemic health para-meters was examined using cross-sectional analysis.
The median age of participants was 47.6 years (range 20-84 years), and 6684 (50.6%) of participants were men. The mean IOP of participants was 15.5 mmHg. The mean IOP, blood pressure and BMI values were significantly higher in men than in women (P < 0.05). The overall prevalence of ocular hypertension, defined as IOP >21 mmHg without signs of glaucomatous visual field loss or optic disc damage, was 6.1% in men and 2.5% in women. Intraocular pressure was associated with mean blood pressure, sex, age and BMI by multiple regression analysis (P < 0.05). The relationship between IOP and age adjusted for sex, mean blood pressure and BMI had a significantly negative tendency for both sexes (P < 0.05). Body mass index had a significantly positive relation with IOP after controlling for age, sex and mean blood pressure in men (P < 0.05), but not in women.
In this Korean population, after multiple adjustment, IOP was found to decrease with age and to increase with BMI in men.
This study examined the influence of age, sex, blood pressure, and obesity index on intraocular pressure (IOP), in order to investigate the relationship between the upper limits of the following two conditions in the general Korean population: the "systolic or diastolic hypertensive and obese" group and the "systolic or diastolic hypotensive and lean" group. A total of 6828 healthy subjects (13,656 eyes) underwent automated multi-phasic tests, including tonometry, blood pressure, visual field, and body mass index. The 6,828 subjects were divided into five groups based on age; less than 40, 40 to 49, 50 to 59, 60 to 69, and over 70 years old. They were also divided into four categories on the basis of sex, age, blood pressure, and obesity index. The mean IOP in males (15.8+/-3.3 mmHg) was significantly higher than in females (14.8+/-3.1 mmHg) (P < 0.05), but this difference decreased proportionally with increasing age. IOP had a tendency to decrease with increasing age (P < 0.05). IOP increased significantly with increasing systolic blood pressure, diastolic blood pressure and obesity index (all, P < 0.05). The mean IOP of the "systolic or diastolic hypertensive and obese" group was higher than that of the "systolic or diastolic hypotensive and lean" group in the general Korean population (P < 0.05). These data could aid investigation into the epidemiological, etiologic and oriental influences related to the risk factors of glaucoma, especially in oriental populations.
Previous cross-sectional Japanese studies have shown that intraocular pressure (IOP) decreases with age. However, central corneal thickness (CCT) variation should also be considered when examining the relationship between age and IOP, since tonometry has an inherent measurement error due to CCT variations. This study investigates the influence of CCT variation on the age-IOP relationship in a Japanese population.
The right eyes of 1317 subjects from 40 to 80 years old selected from a general population using a random sampling method were assessed in cross-section. The IOP was measured with a non-contact tonometer, and CCT was measured with a specular microscope. The relationships between age, IOP, and CCT were assessed using correlation analyses, while the relationship between age and IOP controlled for CCT, blood pressure, and body mass index was investigated using multivariate regression analyses.
The mean (+/- SD) IOP value was 13.6 (+/- 2.6) mmHg in men and 13.3 (+/- 2.6) mmHg in women. The IOP correlated inversely with age in men (r = -0.14, p < 0.001), but showed only a marginal inverse correlation in women (r = -0.07, p = 0.066). The mean (+/- SD) CCT value was 518.3 (+/- 33.2) microm in men and 511.1 (+/- 33.0) microm in women. Only in men was an inverse correlation seen between CCT and age (r = -0.10, p = 0.009), but both genders had positive correlations between CCT and IOP (man: r = 0.44, p < 0.001; woman: r = 0.48, p < 0.001). In multivariate analyses, CCT was shown to have an effect on IOP measurement, however, it was shown that IOP still decreases with age in both sexes even when adjusted for CCT (p = 0.001).
The IOP decreases with age in the Japanese, and CCT variation has practically no effect on the unique age-IOP relationship.
Diabetes and hypertension are recognized risk factors for raised intraocular pressure (IOP). This report examines the longitudinal relationship of hypertension and diabetes to a 4-year IOP change in a black population with high prevalence of these conditions.
Population-based cohort study of a simple random sample of residents of Barbados, West Indies, aged >/=40 years.
A total of 2996 persons without open-angle glaucoma or receiving IOP-lowering medication at baseline.
Participants underwent standardized examinations including applanation tonometry, measurement of blood pressure, and anthropometric indices; a detailed interview; various ocular measurements; and venipuncture for glycosylated hemoglobin (GHb). Diabetes was defined by self-reported physician diagnosis and hypertension by blood pressure >/=140/90 mmHg and/or treatment history.
The 4-year person-based IOP change between baseline and follow-up was defined as the more positive IOP difference in either eye.
An IOP >21 mmHg at baseline was more likely in black and in mixed (black and white) participants (age-gender adjusted odds ratio [OR], 3.9 and 3.8, respectively) than in whites. Similarly, these groups had more hypertension (age-gender adjusted OR, 2.4 and 2.1, respectively) and diabetes (age-gender adjusted OR, 3.9 and 1.7, respectively) than did whites. Mean IOP in black participants increased by 2.5 (standard deviation, 3.9) mmHg over 4 years. Multiple regression analyses showed that baseline diabetes history and hypertension, as well as older age, elevated GHb, higher blood pressures, and lower baseline IOP were associated with a 4-year increase of IOP. The association between diabetes history/GHb and IOP increase became borderline/nonsignificant when persons who underwent cataract surgery during follow-up were excluded.
This report provides new data on the relationship of systemic factors to longitudinal increases in IOP in an African-origin population. Results highlight the increased risk of elevated IOP in populations with high prevalences of diabetes and hypertension.
To assess the relationship between smoking and intraocular pressure.
The Blue Mountains Eye Study examined 3654 residents aged 49 years and older in an area west of Sydney, Australia from 1992 to 1994. A trained interviewer collected a detailed history of smoking. Intraocular pressure was measured using Goldmann applanation tonometry; as the correlation between right and left eyes was very high, only right-eye data are presented. Participants using glaucoma medications or who had evidence of previous cataract surgery were excluded.
Current smokers (15.8% of participants) had slightly higher mean intraocular pressures (16.34 mm Hg) than nonsmokers (16.04 mm Hg). Intraocular pressure (in the right eye) was significantly associated with current smoking, after adjusting for age and sex (P = 0.03). This association remained unchanged after simultaneous adjustment for other variables associated with intraocular pressure, including blood pressure, diabetes, myopia, glaucoma, family history, and pseudoexfoliation (P = 0.02).
This study identified a modest cross-sectional positive association between current smoking and intraocular pressure.
The purpose of this study was to assess the effect that changes in sex hormone levels have on intraocular pressure (IOP) in menopausal women.
Thirty menopausal women on hormone replacement therapy and 32 menopausal women who had never received hormone replacement therapy (HRT), matched for age and duration of amenorrhea, participated in this study. Intraocular pressures were measured with Goldmann applanation tonometer. Serum levels were measured for estradiol, free testosterone, and follicle stimulating hormone (FSH). The influence of serum hormone levels on IOP was assessed by correlation analysis.
The mean IOP of postmenopausal women receiving HRT (13.29 +/- 2.28 mm Hg) was not significantly different from that of menopausal women not receiving HRT (13.56 +/- 2.5 mm Hg, P = 0.24). Higher testosterone levels were associated with higher IOPs in women receiving HRT (r = 0.48, P = 0.02) and in those not receiving HRT (r =0.42, P = 0.003). No significant correlations were observed between IOP and serum levels of estradiol and FSH in either group.
Our data provide evidence for a relation between serum testosterone levels and IOP in menopause. Higher testosterone seems to have a tendency to increase IOP in menopausal women.
Elevated intraocular pressure (IOP), a well-known risk factor for glaucoma, has recently been shown to be associated with some metabolic complications and obesity. We investigated the link between IOP and metabolic disturbances, focusing especially on metabolic syndrome and insulin resistance.
Eye examinations, including IOP measurement, were conducted on 943 subjects (533 men and 410 women). Body mass index (BMI), percent body fat, waist circumference, systolic and diastolic pressure, fasting insulin, glucose, lipids, and other metabolic parameters were measured. The homeostasis model assessment (HOMA) score and McAuley index were calculated to assess whole-body insulin resistance.
Both of these insulin resistance indices showed positive associations with IOP (p < 0.05), even after statistical adjustment for other risk factors. IOP was higher in participants with metabolic syndrome, as compared to those who did not have metabolic syndrome. The mean IOP tended to increase linearly with the presence of increasing numbers of components for metabolic syndrome.
These results suggest that insulin resistance might contribute to an explanation that would account for many previous findings concerning the association between IOP and obesity, hypertension, and diabetes.
To determine the proportion of age-related ophthalmologic diseases discovered in a healthy Japanese adult population, as well as to evaluate the age-related changes in intraocular pressure (IOP) in this population during a 10-year period.
Ophthalmologic surveys were conducted in 1988 and 1998 at Tamaho-cho in Yamanashi Prefecture. The target population of the first survey was 1389 subjects over 40 years of age, and of these, 1250 subjects (473 men and 777 women) participated in the survey. Their mean age was 57.8 +/- 11.9 years. Of these 1250 subjects, 245 subjects participated in the second ophthalmologic survey in 1998. The cases of glaucoma or age-related ophthalmologic diseases developing over the intervening 10-year period were determined among the subjects who had been diagnosed with no ophthalmologic abnormalities in the 1988 survey. We also compared the IOP values of the 219 subjects who were diagnosed with no ophthalmologic abnormalities in either the 1988 or the 1998 survey.
The number of cases in the 1998 survey with newly discovered ocular diseases were as follows: two cases (0.82%) of normal-tension glaucoma, two cases (0.82%) of epiretinal membrane, one case (0.41%) of age-related macular degeneration, one case (0.41%) of angle-closure glaucoma, and one case (0.41%) of branch retinal vein occlusion. The mean IOP of the 219 subjects diagnosed with no ophthalmic abnormalities in either survey was 13.88 +/- 3.04 mmHg in 1988, which declined significantly to 13.16 +/- 2.75 mmHg in 1998 (P < 0.0001).
The 10-year follow-up of the 245 subjects participating in both surveys showed one or two de novo cases of age-related macular degeneration, epiretinal membrane, branch retinal vein occlusion, normal-tension glaucoma, or angle-closure glaucoma. IOP was found to decline significantly with age.
To investigate the relation between change in systemic blood pressures and change in intraocular pressure.
This was a population based study of people 43-86 years old living in Beaver Dam, Wisconsin. Measurements at baseline (1988-90) and 5 year follow up of systemic blood pressures, intraocular pressures, and history of use of blood pressure medications.
Intraocular pressures were significantly correlated with systolic and diastolic blood pressures at both baseline and follow up. There were significant direct correlations between changes in systemic blood pressures and changes in intraocular pressure. There was a 0.21 (95% CI: 0.16 to 0.27) mm Hg increase in IOP for a 10 mm Hg increase in systolic and 0.43 (0.35 to 0.52) mm Hg increase in IOP for a 10 mm Hg increase in diastolic blood pressure. Further adjustment for diabetes and medication use did not alter these associations. Decreased systolic or diastolic blood pressures of more than 10 mm Hg over 5 years were significantly associated with decreased IOP.
Reduced systemic blood pressure is associated with reduced intraocular pressure. This finding should be evaluated in other studies, especially with respect to the possibility of resultant decreased risk of open angle glaucoma.
To determine the distribution of intraocular pressure (IOP) as measured by a noncontact tonometer (NCT) and risk factors responsible for ocular hypertension in elderly Chinese people.
Population-based study of randomly sampled Chinese people 65 years and older in Shihpai, Taipei, Taiwan.
Participants completed an interview and underwent a physical examination and a standardized ophthalmic examination, including IOP measurement with the NCT. People with a history of glaucoma were excluded. Risk factors were assessed using multivariate regression analysis.
Of 1361 study participants examined, 1292 (95.4%) had no history of glaucoma and were therefore included in the study. Their mean +/- SD IOP was 12.9 +/- 3.1 mm Hg. The IOP decreased significantly (P<.001) with age, changing from 13.3 +/- 3.0 mm Hg in participants aged 65 to 69 years to 11.6 +/- 2.8 mm Hg in those 80 years and older. Women had significantly higher IOP than men (P<.001). In the multivariate regression analysis, decreasing age, female sex, increasing systolic blood pressure, a history of diabetes, and alcohol drinking were significantly associated with increasing IOP.
The distribution of IOP in elderly Chinese people is similar to that found in other East Asian people, with a negative age-IOP relationship. The mean IOP values in this elderly Chinese population were lower than in white people but higher than in Japanese people in similarly aged groups. Establishing the epidemiologic characteristics of IOP with the NCT is important for the mass screening of ocular hypertension.