[Show abstract][Hide abstract] ABSTRACT: Background Cigarette smoking is the major cause of chronic obstructive pulmonary disease and emphysema. Recent studies suggest that susceptibility to cigarette smoke may vary by race/ethnicity; however, they were generally small and relied on self-reported race/ethnicity.
Objective To test the hypothesis that relationships of smoking to lung function and per cent emphysema differ by genetic ancestry and self-reported race/ethnicity among Caucasians, African-Americans, Hispanics and Chinese-Americans.
Design Cross-sectional population-based study of adults age 45–84 years in the USA.
Measurements Principal components of genetic ancestry and continental ancestry estimated from one million genome-wide single nucleotide polymorphisms; pack-years of smoking; spirometry measured for 3344 participants; and per cent emphysema on computed tomography for 8224 participants.
Results The prevalence of ever-smoking was: Caucasians, 57.6%; African-Americans, 56.4%; Hispanics, 46.7%; and Chinese-Americans, 26.8%. Every 10 pack-years was associated with −0.73% (95% CI −0.90% to −0.56%) decrement in the forced expiratory volume in 1 s to forced vital capacity (FEV1 to FVC) and a 0.23% (95% CI 0.08% to 0.38%) increase in per cent emphysema. There was no evidence that relationships of pack-years to the FEV1 to FVC, airflow obstruction and per cent emphysema varied by genetic ancestry (all p>0.10), self-reported race/ethnicity (all p>0.10) or, among African-Americans, African ancestry. There were small differences in relationships of pack-years to the FEV1 among male Chinese-Americans and to the FEV1 to FVC ratio with African and Native American ancestry among male Hispanics only.
Conclusions In this large cohort, there was little to no evidence that the associations of smoking to lung function and per cent emphysema differed by genetic ancestry or self-reported race/ethnicity.
[Show abstract][Hide abstract] ABSTRACT: Background:
The contribution of obesity to hypoxemia has not been reported in a community-based study. Our hypothesis was that increasing obesity would be independently associated with lower SpO2 in an ambulatory elderly population.
The Cardiovascular Health Study ascertained resting SpO2 in 2,252 subjects over age 64. We used multiple linear regression to estimate the association of body mass index (BMI) with SpO2 and to adjust for potentially confounding factors. Covariates including age, sex, race, smoking, airway obstruction (based on spirometry), self reported diagnosis of emphysema, asthma, heart failure, and left ventricular function (by echocardiography) were evaluated.
Among 2,252 subjects the mean and median SpO2 were 97.6% and 98.0% respectively; 5% of subjects had SpO2 values below 95%. BMI was negatively correlated with SpO2 (Spearman R = -0.27, P < .001). The mean difference in SpO2 between the lowest and highest BMI categories (< 25 kg/m(2) and ≥ 35 kg/m(2)) was 1.33% (95% CI 0.89-1.78%). In multivariable linear regression analysis, SpO2 was significantly inversely associated with BMI (1.4% per 10 units of BMI, 95% CI 1.2-1.6, for whites/others, and 0.87% per 10 units of BMI, 95% CI 0.47-1.27, for African Americans).
We found a narrow distribution of SpO2 values in a community-based sample of ambulatory elderly. Obesity was a strong independent contributor to a low SpO2, with effects comparable to or greater than other factors clinically associated with lower SpO2.
No preview · Article · Oct 2012 · Respiratory care
[Show abstract][Hide abstract] ABSTRACT: Metabolic syndrome (MetS), Type 2 diabetes (T2D), and cardiovascular disease (CVD) share an inflammatory etiology and are known to be influenced by diet. We investigated associations of hypothesized prooxidative (Fe) and antioxidative (Zn, Mg, β-carotene, vitamin C, vitamin E) micronutrients with incident MetS, T2D, and CVD in the Multi-Ethnic Study of Atherosclerosis. Participants, 45-84 y at baseline (2000-2002), were followed through 2010. Diet was assessed by FFQ. After adjusting for demographics and behavioral confounders, including BMI, dietary vitamin E intake was inversely associated with incident MetS and CVD [HR for extreme quintiles: MetS = 0.78 (95% CI = 0.62, 0.97), P-trend = 0.01; CVD: HR = 0.69 (95% CI = 0.46, 1.03), P-trend = 0.04]. Intakes of heme iron and Zn from red meat, but not from other sources, were positively associated with risk of MetS [heme iron from red meat: HR = 1.25 (95% CI = 0.99,1.56), P-trend = 0.03; Zn from red meat: HR = 1.29 (95% CI = 1.03,1.61), P-trend = 0.04] and CVD [heme iron from red meat: HR = 1.65 (95% CI = 1.10,2.47), P-trend = 0.01; Zn from red meat: HR = 1.51 (95% CI = 1.02, 2.24), P-trend = 0.01]. Dietary intakes of nonheme iron, Mg, vitamin C, and β-carotene were not associated with risk of MetS, T2D, or CVD. Data provided little support for the associations between specific micronutrients and MetS, T2D, or CVD. However, nutrients consumed in red meat, or red meat as a whole, may increase risk of MetS and CVD.
Full-text · Article · Mar 2012 · Journal of Nutrition
[Show abstract][Hide abstract] ABSTRACT: Airflow obstruction is an independent risk factor for cardiovascular events in the general population. The affected vascular bed and contribution of emphysema to cardiovascular risk are unclear. We examined whether an obstructive pattern of spirometry and quantitatively defined emphysema were associated with subclinical atherosclerosis in the carotid, peripheral and coronary circulations. The Multi-Ethnic Study of Atherosclerosis recruited participants aged 45-84 yrs without clinical cardiovascular disease. Spirometry, carotid intima-media thickness (IMT), ankle-brachial index (ABI) and coronary artery calcium (CAC) were measured using standard protocols. Percentage of emphysema-like lung was measured in the lung windows of cardiac computed tomography scans among 3,642 participants. Multiple linear regression was used to adjust for cardiac risk factors, including C-reactive protein. Decrements in forced expiratory volume in 1 s (FEV(1)) and FEV(1)/forced vital capacity ratio were associated with greater internal carotid IMT, particularly among smokers (p=0.03 and p<0.001, respectively) whereas percentage emphysema was associated with reduced ABI regardless of smoking history (p=0.004). CAC was associated with neither lung function (prevalence ratio for the presence of CAC in severe airflow obstruction 0.99, 95% CI 0.91-1.07) nor percentage emphysema. An obstructive pattern of spirometry and emphysema were associated distinctly and independently with subclinical atherosclerosis in the carotid arteries and peripheral circulation, respectively, and were not independently related to CAC.
Full-text · Article · Oct 2011 · European Respiratory Journal
[Show abstract][Hide abstract] ABSTRACT: Few studies have examined associations of dietary micronutrients with markers of inflammation and subclinical atherosclerosis. The present study investigated associations of heme iron, nonheme iron, zinc (Zn), magnesium (Mg), β-carotene, vitamin C, and vitamin E with C-reactive protein (CRP), IL-6, total homocysteine (tHcy), fibrinogen, coronary artery calcium, and common and internal carotid artery intima media thickness. Micronutrient intakes and markers of inflammation and subclinical atherosclerosis were studied in 5,181 participants from the Multi-Ethnic Study of Atherosclerosis who were aged 45-84 y and free of diabetes and cardiovascular disease. Models were adjusted for energy intake, demographics, lifestyle characteristics, and BMI. Dietary nonheme iron and Mg intakes were inversely associated with tHcy concentrations (mean tHcy: 9.11, 8.86, 8.74, 8.71, and 8.50 μmol/L, and 9.20, 9.00, 8.65, 8.76, and 8.33 μmol/L across increasing quintiles of nonheme iron and Mg, respectively; P-trend < 0.001 for both). However, dietary Zn and heme iron were positively associated with CRP [mean: 1.73, 1.75, 1.78, 1.88, and 1.96 mg/L across increasing quintiles of Zn and 1.72, 1.76, 1.83, 1.86, and 1.94 mg/L across increasing quintiles of heme iron (P-trend = 0.002 and 0.01, respectively). Other tested micronutrient-marker associations were not significant. In conclusion, of the 49 tested associations, only 7 were significant. Although this study does not provide strong support for associations between the micronutrients and markers of inflammation and subclinical atherosclerosis, the results are consistent with dietary guidelines that advocate for a balanced diet that includes a variety of plant foods containing Mg, Zn, and nonheme iron.
Full-text · Article · Jun 2011 · Journal of Nutrition
[Show abstract][Hide abstract] ABSTRACT: Forced expiratory volume in one second strongly predicts mortality from cardiovascular disease. FEV(1) has been associated with aortic stiffness a strong independent predictor of cardiovascular mortality. However, the anatomical site and possible mechanisms linking aortic stiffness and lung function are unknown. We therefore examined if FEV(1) and CT percent emphysema were associated with calcification of the abdominal aorta or reduced distensibility of the proximal thoracic aorta.The Multi-Ethnic Study of Atherosclerosis (MESA) measured aortic calcification on cardiac and abdominal CT scans and proximal aortic distensibility using magnetic resonance among participants aged 45-84 years without clinical cardiovascular disease. Spirometry was measured following ATS/ERS guidelines and percent emphysema was measured in the lung fields of cardiac CT scans. Multivariate analyses adjusted for age, sex, race/ethnicity and cardiovascular risk factors. Of 1,917 participants with aortic distensibility measures, 13% were current and 38% were former smokers. Eighteen percent had airflow limitation without asthma. FEV(1) was associated with the extent of distal aortic calcification (0.76; 95%CI 0.60-0.97, p = 0.02) but not proximal aortic calcification or proximal aortic distensibility (-0.04 mmHg(-1); 95%CI -0.16-0.09 mmHg(-1), p = 0.60). Percent emphysema was associated with neither measure. FEV(1) was associated with severity of distal aortic calcification where it was present independently of smoking and other cardiovascular risk factors but not with distensibility or calcification of the proximal aorta.
[Show abstract][Hide abstract] ABSTRACT: Higher socioeconomic status (SES) has been associated with lower respiratory mortality and better lung function, but whether a similar gradient exists for computed tomography (CT) measures of subclinical emphysema is unknown.
The Multi-Ethnic Study of Atherosclerosis (MESA) recruited African-American, Chinese, Hispanic, and white participants, ages 45 to 84 years, without clinical cardiovascular disease, from six US sites between 2000 and 2002. The MESA Lung Study assessed percent emphysema, defined based on the proportion of pixels below an attenuation threshold of 910 HU from lung windows of cardiac CT scans. Generalized linear models were adjusted for demographic characteristics, height, body mass index, history of respiratory illness, occupational and residential exposures, tobacco use, and CT scanner type.
Among 3706 participants with a mean age of 61 (±10), the median value for percent emphysema was 18 (interquartile range = 20). Compared with those who did not complete high school, participants with a graduate degree had a higher percent emphysema (difference of 4; P < .001). Income and wealth were also positively associated with percent emphysema. In contrast, higher SES was associated with better lung function. Descriptive and subgroup analyses were used to explore potential explanations for divergent results, including the possibility that suboptimal inspiration during CT scanning would decrease percent emphysema, making the lungs appear healthier when effort is relatively poor.
Although SES indicators were positively associated with subclinical emphysema detectable on CT scan, this unexpected association may highlight potential bias because of effort dependence of both CT measures and spirometry.
Full-text · Article · Feb 2011 · Academic radiology
[Show abstract][Hide abstract] ABSTRACT: Dairy products contain vitamin D and other nutrients that may be beneficial for lung function, but they are also high in fats that may have mixed effects on lung function. However, the overall associations of dairy intake with lung density and lung function have not been studied.
We examined the cross-sectional relationships between dairy intake and computed tomography (CT) lung density and lung function in the Multi-Ethnic Study of Atherosclerosis (MESA). Total, low-fat, and high-fat dairy intakes were quantified from food frequency questionnaire responses of men and women who were ages 45-84 years and free of clinical cardiovascular disease. The MESA-Lung Study assessed CT lung density from cardiac CT imaging and prebronchodilator spirometry among 3965 MESA participants.
Total dairy intake was inversely associated with apical-basilar difference in percent emphysema and positively associated with forced vital capacity (FVC) (the multivariate-adjusted mean difference between the highest and lowest quintiles of total dairy intake was -0.92 [p for trend = 0.04] for apical-basilar difference in percent emphysema and 72.0 mL [p = 0.01] for FVC). Greater low-fat dairy intake was associated with higher alpha (higher alpha values indicate less emphysema) and lower apical-basilar difference in percent emphysema (corresponding differences in alpha and apical-basilar difference in percent emphysema were 0.04 [p = 0.02] and -0.98 [p = 0.01] for low-fat dairy intake, respectively). High-fat dairy intake was not associated with lung density measures. Greater low- or high-fat dairy intake was not associated with higher forced expiratory volume in 1 second (FEV(1)), FVC, and FEV(1)/FVC.
Higher low-fat dairy intake but not high-fat dairy intake was associated with moderately improved CT lung density.
No preview · Article · Oct 2010 · Journal of the American College of Nutrition
[Show abstract][Hide abstract] ABSTRACT: Cigarette smoking is the major cause of chronic obstructive pulmonary disease, but studies on the contribution of other smoking techniques are sparse.
To determine whether pipe and cigar smoking was associated with elevated cotinine levels, decrements in lung function, and increased odds of airflow obstruction.
Population-based sample from 6 U.S. communities.
Men and women aged 48 to 90 years without clinical cardiovascular disease at enrollment who were part of MESA (Multi-Ethnic Study of Atherosclerosis).
The MESA Lung Study measured spirometry according to American Thoracic Society guidelines and urine cotinine levels by immunoassay on a subsample of MESA. Pipe-years and cigar-years were calculated as years from self-reported age of starting to age of quitting (or to current age in current users) multiplied by pipe-bowls or cigars per day.
Of 3528 participants, 9% reported pipe smoking (median, 15 pipe-years), 11% reported cigar smoking (median, 6 cigar-years), and 52% reported cigarette smoking (median, 18 pack-years). Self-reported current pipe and cigar smokers had elevated urine cotinine levels compared with never-smokers. Pipe-years were associated with decrements in FEV(1), and cigar-years were associated with decrements in the FEV(1)-FVC ratio. Participants who smoked pipes or cigars had increased odds of airflow obstruction whether they had also smoked cigarettes (odds ratio, 3.43 [95% CI, 1.75 to 6.71]; P < 0.001) or not (odds ratio, 2.31 [CI, 1.04 to 5.11]; P = 0.039) compared with participants with no smoking history.
Pipe and cigar smoking increased urine cotinine levels and was associated with decreased lung function and increased odds of airflow obstruction, even in participants who had never smoked cigarettes.
National Heart, Lung, and Blood Institute, National Institutes of Health.
Preview · Article · Feb 2010 · Annals of internal medicine
[Show abstract][Hide abstract] ABSTRACT: Very severe chronic obstructive pulmonary disease causes cor pulmonale with elevated pulmonary vascular resistance and secondary reductions in left ventricular filling, stroke volume, and cardiac output. We hypothesized that emphysema, as detected on computed tomography (CT), and airflow obstruction are inversely related to left ventricular end-diastolic volume, stroke volume, and cardiac output among persons without very severe lung disease.
We measured left ventricular structure and function with the use of magnetic resonance imaging in 2816 persons who were 45 to 84 years of age. The extent of emphysema (expressed as percent emphysema) was defined as the percentage of voxels below -910 Hounsfield units in the lung windows on cardiac computed tomographic scans. Spirometry was performed according to American Thoracic Society guidelines. Generalized additive models were used to test for threshold effects.
Of the study participants, 13% were current smokers, 38% were former smokers, and 49% had never smoked. A 10-point increase in percent emphysema was linearly related to reductions in left ventricular end-diastolic volume (-4.1 ml; 95% confidence interval [CI], -3.3 to -4.9; P<0.001), stroke volume (-2.7 ml; 95% CI, -2.2 to -3.3; P<0.001), and cardiac output (-0.19 liters per minute; 95% CI, -0.14 to -0.23; P<0.001). These associations were of greater magnitude among current smokers than among former smokers and those who had never smoked. The extent of airflow obstruction was similarly associated with left ventricular structure and function, and smoking status had similar modifying effects on these associations. Percent emphysema and airflow obstruction were not associated with the left ventricular ejection fraction.
In a population-based study, a greater extent of emphysema on CT scanning and more severe airflow obstruction were linearly related to impaired left ventricular filling, reduced stroke volume, and lower cardiac output without changes in the ejection fraction.
Full-text · Article · Jan 2010 · New England Journal of Medicine
[Show abstract][Hide abstract] ABSTRACT: Maximum inspiratory pressure (MIP) is an important and noninvasive index of diaphragm strength and an independent predictor of all-cause mortality. The ability of adults over a wide age range and multiple race/ethnicities to perform MIP tests has previously not been evaluated.
The Multi-Ethnic Study of Atherosclerosis recruited white, African American, Hispanic, and Chinese American participants, ages 45-84 years, and free of clinical cardiovascular disease in 6 United States cities. MIP was measured using standard techniques among 3,849 Multi-Ethnic Study of Atherosclerosis participants. The MIP quality goal was 5 maneuvers, with the 2 largest values matching within 10 cm H2O. Correlates of MIP quality and values were assessed in logistic and linear regression models.
The 3,849 participants with MIP measures were 51% female, 35% white, 26% African American, 23% Hispanic, and 16% Chinese American. Mean+/-SD MIP was 73+/-26 cm H2O for women and 97+/-29 cm H2O for men. The quality goal was achieved by 83% of the cohort and was associated with female sex, older age, race/ethnicity, study site, low ratio of forced expiratory volume in the first second to forced vital capacity (FEV1/FVC), and wheeze with dyspnea. The multivariate correlates of MIP were male sex, younger age, higher body mass index, shorter height, higher FVC, higher systolic blood pressure (in women) and health status (in men). There were no clinically important race/ethnic differences in MIP values.
Race-specific reference equations for MIP are unnecessary in the United States. More than 80% of adults can be successfully coached for 5 maneuvers, with repeatability within 10 cm H2O.
[Show abstract][Hide abstract] ABSTRACT: Cardiac computed tomographic (CT) scans for the assessment of coronary calcium scores include approximately 70% of the lung volume and may be useful for the quantitative assessment of emphysema. The reproducibility of lung density measures from cardiac computed tomography and their validity compared to lung density measures from full-lung scans is unknown.
The Multi-Ethnic Study of Atherosclerosis (MESA) performed paired cardiac CT scans for 6814 participants at baseline and at follow-up. The MESA-Lung Study assessed lung density measures in the lung fields of these cardiac scans, counting voxels below -910 HU as moderate-to-severe emphysema-like lung regions. We evaluated: 1) the reproducibility of lung density measures among 120 randomly selected participants; 2) the comparability of measures acquired on electron beam CT (EBCT) and multidetector CT (MDCT) scanners among 10 participants; and 3) the validity of these measures compared to full-lung scans among 42 participants. Limits of agreement were determined using Bland-Altman approaches.
Percent emphysema measures from paired cardiac scans were highly correlated (r = 0.92-0.95) with mean difference of -0.05% (95% limits of agreement: -8.3, 8.4%). Measures from EBCT and MDCT scanners were comparable (mean difference -0.9%; 95% limits of agreement: -5.1, 3.3%). Percent emphysema measures from MDCT cardiac and MDCT full-lung scans were highly correlated (r = 0.93) and demonstrated reasonable agreement (mean difference 2.2%; 95% limits of agreement: -9.2, 13.8%).
Although full-lung imaging is preferred for the quantification of emphysema, the lung imaging from paired cardiac computed tomography provided a reproducible and valid quantitative assessment of emphysema in a population-based sample.
[Show abstract][Hide abstract] ABSTRACT: Cigarette smoking is a risk factor for diffuse parenchymal lung disease. Risk factors for subclinical parenchymal lung disease have not been described.
To determine if cigarette smoking is associated with subclinical parenchymal lung disease, as measured by spirometric restriction and regions of high attenuation on computed tomography (CT) imaging.
We examined 2,563 adults without airflow obstruction or clinical cardiovascular disease in the Multi-Ethnic Study of Atherosclerosis, a population-based cohort sampled from six communities in the United States. Cumulative and current cigarette smoking were assessed by pack-years and urine cotinine, respectively. Spirometric restriction was defined as a forced vital capacity less than the lower limit of normal. High attenuation areas on the lung fields of cardiac CT scans were defined as regions having an attenuation between -600 and -250 Hounsfield units, reflecting ground-glass and reticular abnormalities. Generalized additive models were used to adjust for age, gender, race/ethnicity, smoking status, anthropometrics, center, and CT scan parameters.
The prevalence of spirometric restriction was 10.0% (95% confidence interval [CI], 8.9-11.2%) and increased relatively by 8% (95% CI, 3-12%) for each 10 cigarette pack-years in multivariate analysis. The median volume of high attenuation areas was 119 cm(3) (interquartile range, 100-143 cm(3)). The volume of high attenuation areas increased by 1.6 cm(3) (95% CI, 0.9-2.4 cm(3)) for each 10 cigarette pack-years in multivariate analysis.
Smoking may cause subclinical parenchymal lung disease detectable by spirometry and CT imaging, even among a generally healthy cohort.
Full-text · Article · Jul 2009 · American Journal of Respiratory and Critical Care Medicine
[Show abstract][Hide abstract] ABSTRACT: The cardioprotective effects of long-chain n-3 polyunsaturated fatty acids (PUFAs) and fish consumption have been observed. However, data on the specific associations of these dietary factors with inflammation and endothelial activation are sparse. A cross-sectional study was conducted of 5,677 men and women from the Multi-Ethnic Study of Atherosclerosis (MESA) cohort, including African Americans, Caucasians, Chinese, and Hispanics aged 45 to 84 years and free of clinical cardiovascular disease. Dietary information was collected using a self-administered food frequency questionnaire. Multivariate linear regression analyses were used to examine relations between the intake of long-chain n-3 PUFAs, nonfried fish, and fried fish and biomarkers of inflammation and endothelial activation. Long-chain n-3 PUFA intake was inversely associated with plasma concentrations of interleukin-6 (p = 0.01) and matrix metalloproteinase-3 (p = 0.03) independent of age, body mass index, physical activity, smoking, alcohol consumption, and dietary variables. Nonfried fish consumption was inversely related to C-reactive protein (p = 0.045) and interleukin-6 (p <0.01), and fried fish consumption was inversely related to soluble intercellular adhesion molecule-1 (p <0.01) but was not associated with other biomarkers after adjustment for potential confounders. In conclusion, the results of this study suggest that the dietary intake of long-chain n-3 PUFAs and fish is inversely associated with concentrations of some biomarkers, reflecting lower levels of inflammation and endothelial activation. These results may partially explain the cardioprotective effects of fish consumption.
Preview · Article · May 2009 · The American journal of cardiology