[show abstract][hide abstract] ABSTRACT: BACKGROUND: Young adults born preterm at very-low-birth-weight (VLBW, ≤1500g) have higher levels of cardiovascular risk factors, including impaired glucose regulation, than their term-born peers. This could be mediated through altered hypothalamic-pituitary-adrenal axis (HPAA) response to stress. OBJECTIVE: To compare HPAA, glucose and insulin responses provoked by psychosocial stress in VLBW subjects versus a comparison group of term-born controls. DESIGN AND PARTICIPANTS: We studied 54 unimpaired young adults, aged 19-27 years, born at VLBW and a comparison group of 40 adults born at term, group-matched for age, sex and birth hospital, from one regional centre in Southern Finland. The participants underwent a standardized psychosocial stress test (Trier Social Stress Test, TSST). MEASUREMENTS: In conjunction with TSST we measured salivary cortisol, plasma ACTH, cortisol, glucose and insulin. Data were analyzed with mixed effects model and multiple linear regression analyses. RESULTS: Baseline concentrations for cortisol, ACTH, insulin and glucose were similar in VLBW and comparison groups. During TSST, analyzed with mixed effects model, overall concentrations of plasma cortisol were 17.2% lower (95% CI; 3.5 to 28.9) in the VLBW group. The VLBW group also had lower salivary (P=0.04) and plasma cortisol (P=0.02) responses to TSST. Insulin and glucose concentrations correlated with changes in cortisol concentrations. Accordingly, VLBW subjects had 26.5% lower increment of insulin (95% CI; 9.8 to 40.1). Analyses were adjusted for age, sex, BMI, hormonal contraception, menstrual cycle phase, time of day and parental education. CONCLUSIONS: VLBW adults have lower HPAA responses to psychosocial stress than term-born controls. This is accompanied by a lower insulin response. This article is protected by copyright. All rights reserved.
[show abstract][hide abstract] ABSTRACT: The influence of environmental conditions early in life - including temperature and season - on health later in life has so far not attracted much attention.
Using data from the Helsinki Birth Cohort Study of 13,345 men and women, the influence of temperature and season at month of conception on birth weight, and on cardiovascular diseases and obesity-related traits in later life was studied.
Linear regressions were fitted to examine the relationship between birth weight/obesity-related variables/hypertension and alternatively month of conception and average temperature of month of conception. The incidence of both coronary heart disease and cerebrovascular disease was assumed to follow a Weibull hazard model, and was modelled accordingly using survival analysis techniques.
In women, unusually cold temperatures at month of conception predicted lower body mass index (BMI) and fat percentage, and protected from obesity. Warmer temperatures at month of conception were associated with higher risk for hypertension. In men, warmer temperatures around conception predicted lower BMI. No seasonal influences were detected on obesity-related variables, nor were there seasonal or temperature mediated influences on birth weight, coronary heart disease or cerebrovascular disease observed.
We suggest that ambient temperature has an influence on obesity-related outcomes and hypertension. This merits further study, also with regard to other health outcomes and from a global perspective.
International journal of circumpolar health. 01/2013; 72.
[show abstract][hide abstract] ABSTRACT: Background/objectives:Shorter leukocyte telomere length (LTL) is associated with several chronic diseases, but only a few studies have assessed the association between dietary factors and LTL. Our objective was to study the association between fats, fruits, vegetables and LTL in a cross-sectional study design. We hypothesized that intakes of fruits and vegetables would be positively associated with LTL and that intakes of fats, and especially saturated fatty acids (SFAs), would be negatively associated with LTL.Subjects/methods:LTL was measured by quantitative real-time polymerase chain reaction in 1942 men and women aged 57-70 years from the Helsinki Birth Cohort Study. We assessed the whole diet by a validated semiquantitative 128-item food-frequency questionnaire.Results:In general, there were only a few significant results. However, total fat and SFA intake (P=0.04 and 0.01, respectively) were inversely associated with LTL in men adjusting for age and energy intake. In women, vegetable intake was positively associated with LTL (P=0.05). Men consuming the most butter and least fruits had significantly shorter telomeres than those consuming the lowest amounts of butter and highest amounts of fruits (P=0.05). We found no association between LTL and body mass index, waist-hip ratio, smoking, physical activity or educational attainment.Conclusions:In this cross-sectional study of elderly men and women, there were only a few statistically significant effects of diet, but in general they support the hypothesis that fat and vegetable intakes were associated with LTL.European Journal of Clinical Nutrition advance online publication, 17 October 2012; doi:10.1038/ejcn.2012.143.
European journal of clinical nutrition 10/2012; · 3.07 Impact Factor
[show abstract][hide abstract] ABSTRACT: The incidence of type 2 diabetes is increasing among Finnish young adults. A slightly increased risk in men was found in the north-east and western part of the country. The higher risk areas in women were found in the western coastal area and in eastern Finland. The present register-based study aimed to evaluate the regional association of the incidence of type 2 diabetes among young adults with the concentration of magnesium in local ground water. The association was evaluated using Bayesian modeling of geo-referenced data aggregated into a regular 10 km × 10 km grid cells. No marked association was found, although suggestive findings were detected for magnesium in well water and diabetes in young adult women. The results of this register-based study did not completely rule out the association of well water magnesium with the geographical variation of type 2 diabetes. The incidence of type 2 diabetes was much higher among individuals aged 40 or over. These suggestive findings indicate that the association between magnesium and type 2 diabetes would also be worth examining among individuals over 40 years of age.
Environmental Research 11/2011; 112:126-8. · 3.24 Impact Factor
[show abstract][hide abstract] ABSTRACT: Low birth-weight is associated with an increased risk of cardiovascular disease, hypertension, and the metabolic syndrome (MetS) in adulthood. Resting metabolic rate (RMR) has been suggested to be associated with the development of obesity as well as MetS and might be an indirect indicator of sympathetic activity. This study's aim was to examine the association between birth-weight and adult RMR.
A total of 896 men and women from the Helsinki Birth Cohort Study born 1934-44, for whom a detailed set of birth records were available, underwent measurement of body composition and RMR in adulthood.
Among women, birth-weight adjusted for age and fat-free mass (FFM) was inversely associated with RMR (r = -0.12; P < 0.01). For men, a u-shaped relationship was observed, both independently and after adjustment for age, fat mass, and FFM (P = 0.05 for final model).
The sex-specific differences for the association between birth-weight and adult RMR might partly be explained by differences in the developmental programming of the sympathetic nervous system between men and women. The higher adjusted RMR among those with the lowest birth-weights is consistent with previous evidence of higher sympathetic drive among these individuals.
Annals of medicine 02/2011; 44(3):296-303. · 3.52 Impact Factor
[show abstract][hide abstract] ABSTRACT: Epidemiologic evidence suggests that prenatal growth influences adult blood pressure. Nutritional factors, including salt intake, also influence blood pressure. However, it is unknown whether prenatal growth modifies the association between salt intake and blood pressure in later life.
Our aim was to examine whether the relation between salt intake and adult blood pressure is modified by birth weight.
We studied 1512 participants of the Helsinki Birth Cohort Study who were born between 1934 and 1944. Information on birth weight was abstracted from birth records, and preterm births were excluded. During a clinical study, at the mean age of 62 y, blood pressure, weight, and height were measured. Diet was assessed with a validated food-frequency questionnaire. The relation between salt intake and blood pressure was tested by a piecewise multivariate regression analysis with the best fitting breakpoints to birth weight and salt intake.
An inverse association was observed between birth weight and systolic blood pressure (SBP) (P = 0.02). No significant association between salt intake and SBP was observed in the whole study population. Of those whose birth weight was ≤3050 g, a 1-g higher daily salt intake was associated with a 2.48-mm Hg (95% CI: 0.40, 4.52 mm Hg) higher SBP (P = 0.017) until the saturation point of 10 g. Of those whose birth weight exceeded 3050 g, SBP was not significantly associated with salt intake. For diastolic blood pressure, no significant relations were observed.
Adult individuals with low birth weight may be particularly sensitive to the blood pressure-raising effect of salt.
American Journal of Clinical Nutrition 11/2010; 93(2):422-6. · 6.50 Impact Factor
[show abstract][hide abstract] ABSTRACT: Background. Increased rates of coronary heart disease (CHD) and cerebrovascular disease in later life have been repeatedly observed in subjects with low birth-weight. One possible reason for low birth-weight is prenatal stress. Little is known about the influence of prenatal stress on lifelong health outcomes. Aims. In this study we investigate the influence of prenatal stress on CHD and cerebrovascular disease incidence in adult life. Methods. We analysed data originating from the Helsinki Birth Cohort Study including hospital data from all men and women born between 1934 and 1944 (n = 13,039) in two hospitals of Helsinki. We estimated the hazard function based on Weibull distribution. We compared those exposed and unexposed to bombings while in utero in terms of lifelong CHD and cerebrovascular disease hazard. Results. In women exposed to bombings while in utero, we observed higher survival rates of both CHD and cerebrovascular disease than in those unexposed. In men, the results were ambiguous. Conclusions. Our findings suggest that prenatal exposure to severe stress may be associated with protective effects on the development of CHD in later life.
Annals of medicine 10/2010; 43(7):555-61. · 3.52 Impact Factor
[show abstract][hide abstract] ABSTRACT: To determine if there is a worldwide seasonal pattern in the clinical onset of Type 1 diabetes.
Analysis of the seasonality in diagnosis of Type 1 diabetes was based on the incidence data in 0- to 14-year-old children collected by the World Health Organization Diabetes Mondiale (WHO DiaMond) Project over the period 1990-1999. One hundred and five centres from 53 countries worldwide provided enough data for the seasonality analysis. The incidence seasonality patterns were also determined for age- and sex-specific groups.
Forty-two out of 105 centres exhibited significant seasonality in the incidence of Type 1 diabetes (P < 0.05). The existence of significant seasonal patterns correlated with higher level of incidence and of the average yearly counts. The correlation disappeared after adjustment for latitude. Twenty-eight of those centres had peaks in October to January and 33 had troughs in June to August. Two out of the four centres with significant seasonality in the southern hemisphere demonstrated a different pattern with a peak in July to September and a trough in January to March.
The seasonality of the incidence of Type 1 diabetes mellitus in children under 15 years of age is a real phenomenon, as was reported previously and as is now demonstrated by this large standardized study. The seasonality pattern appears to be dependent on the geographical position, at least as far as the northern/southern hemisphere dichotomy is concerned. However, more data are needed on the populations living below the 30th parallel north in order to complete the picture.
Diabetic Medicine 08/2009; 26(7):673-8. · 3.24 Impact Factor
[show abstract][hide abstract] ABSTRACT: To examine the effects of the size of the mother and the newborn, including placental weight and gestational age at delivery, on the risk for young adult-onset type 1 diabetes (T1DM) and type 2 diabetes (T2DM).
Subjects with T1DM and T2DM aged 15-39 at diagnosis between the years 1992 and 1996. The number of case-control pairs was 858 for T1DM and 355 for T2DM.
Diabetic subjects were identified from the Finnish national healthcare registers and reports from diabetes nurses. Control subjects were obtained from the population register. Data on perinatal factors were obtained from the original healthcare records. The odds ratios (ORs) for both types of diabetes were estimated using conditional logistic regression.
The risk for early-onset T2DM decreased with increasing birthweight until 4.2 kg (OR 0.49 (95% confidence interval 0.37-0.66) per 1 kg), but with birthweight above 4.2 kg the risk increased (OR 4.8 (1.3-17.6) per 1 kg). The risk for T2DM decreased also with increasing birth length (OR 0.88 (0.81-0.95) per 1 cm), body mass index at birth (OR 0.81 (0.73-0.90) per 1 kg/m2), and placental weight (OR 0.77 (0.61-0.98) per 100 g). The latter was not significant when adjusted for birthweight. The examined perinatal factors did not affect the risk for T1DM in young adults.
Birth size significantly affects the risk for T2DM diagnosed in young adulthood but no evidence was found of an association between late-onset T1DM and perinatal factors.
[show abstract][hide abstract] ABSTRACT: The aim of this study was to examine the effects of childhood BMI growth dynamics on the risk of developing young adult-onset type 1 and type 2 diabetes.
Finnish national healthcare registers were used to identify individuals with diabetes diagnosed between 1992 and 1996 at 15-39 years of age. Non-diabetic control participants were chosen from the National Population Registry. Anthropometric measurements were obtained from the original child welfare clinic records. Only the case-control pairs with sufficient growth data recorded were included in the analyses (218/1,388 for type 1 diabetes [16%] and 64/1,121 for type 2 diabetes [6%]). Two developmental stages in BMI growth (the points of infancy maximum BMI and the BMI rebound) were examined, and conditional logistic regression was applied to the variables of interest.
The risk for type 1 diabetes increased 1.19-fold per 1 kg/m(2) rise in the infancy maximum BMI (p = 0.02). In addition, there was a 1.77-fold increase in the risk for type 2 diabetes per 1 kg/m(2) rise in the level of BMI at the BMI rebound (p = 0.04). Higher values of BMI at these points corresponded to a larger BMI gain from birth to that developmental stage. Age at the infancy maximum BMI or age at the BMI rebound did not affect the risk for either type of diabetes.
The BMI gain in infancy among individuals who subsequently developed young adult-onset type 1 diabetes was faster than that of those who remained healthy. The excess BMI gain in individuals who developed young adult-onset type 2 diabetes could already be seen during early childhood.
[show abstract][hide abstract] ABSTRACT: Previous studies have suggested that seasonal variation and weather conditions have an influence on the incidence and mortality of acute myocardial infarction (AMI). The influence of these factors on AMI: case fatality is less studied. Aims. The aim of this study was to examine the temporal variation of AMI case fatality and the effect of daily weather conditions on it.
We analysed death registry and hospital discharge data from all men and women (n=7328) with their first AMI occurrence in the seven largest cities in Finland in the years 1983, 1988, and 1993, aged 25 to 74 years.
The mean annual 28-day case fatality was 44%. We found significant weekly and monthly variation of case fatality (P<0.001). The December holiday season had the highest case fatality throughout the year in women and men aged 65-74 years (P<0.05). The highest weekly case fatality was on Sundays; it differed significantly from the rest of the weekdays only for the oldest age-group (64-74) (P<0.01).
There is significant weekly and monthly variation in case fatality of AMI. The highest case fatality risk for AMI is during the Christmas season and on Sundays. Weather conditions were not found to have an effect on the case fatality.
Annals of medicine 10/2008; 41(1):73-80. · 3.52 Impact Factor
[show abstract][hide abstract] ABSTRACT: The protective role of water hardness and Mg in cardiovascular illness has been suggested in several epidemiological studies. In the present ecological study, the association of Ca, Mg, Al, Cu, F, Fe, Zn and NO3 in local ground water and spatial variation of acute myocardial infarction (AMI) incidence among men and women 35–74 years of age in rural Finland in 1991–2003 were examined. Data on AMI cases, 67,755 men and 25,450 women, were obtained from the Finnish Cardiovascular Disease Register. The statistical analysis was carried out using Bayesian modeling. 10 × 10 km grid cells were used instead of administrative boundaries to partition the study area. On average, 1 mg/L increment in Mg level in local ground water was associated with 2% (95% HDR −0.0391, −0.0028) decrease in incidence of AMI in the rural population. In conclusion, high AMI incidence in eastern Finland is associated with soft ground water, low in Mg.
[show abstract][hide abstract] ABSTRACT: The aim of this study was to examine the effects of birth order and parental age on the risk of type 1 and type 2 diabetes among Finnish individuals aged 15-39 years.
Data on all cases of type 1 diabetes (n = 1,345) and type 2 diabetes (n = 1,072), diagnosed between 1992 and 1996, were collected from four sources: standardised national reports from diabetes nurses, the National Hospital Discharge Register, the Drug Prescription Register and the Drug Reimbursement Register. Information on matched controls and the family members of all study subjects were obtained from the National Population Registry. The odds ratios (ORs) for both types of diabetes were estimated using a conditional logistic regression model.
There was a U-shaped relationship between maternal age and the risk of type 2 diabetes in the offspring: the risk was higher in children born to young and old mothers compared with children born to mothers aged around 30 years. The children born second (OR 0.76, 95% CI 0.62-0.94), third (OR 0.73, 95% CI 0.55-0.95), or fourth (OR 0.66, 95% CI 0.47-0.94) had a lower risk of type 2 diabetes than the first-born children. Maternal age, paternal age, and birth order did not have an effect on the risk of type 1 diabetes in the individuals aged 15-39 years at the time of diagnosis.
Maternal age and birth order are both associated with the risk of early-onset type 2 diabetes. However, part of these associations may be due to low birthweight. In this study neither parental age nor birth order showed a significant association with the risk of type 1 diabetes diagnosed after 15 years of age.
[show abstract][hide abstract] ABSTRACT: A shared and additive genetic variance component-long-term survivor (LTS) model for familial aggregation studies of complex diseases with variable age-at-onset phenotype and non-susceptible subjects in the study cohort is proposed. LTS has been used from the early 1970s, especially in epidemiological studies of cancer. The LTS model utilizes information on the age at onset (survival) distribution to make inference on partially latent susceptibility. Bayesian modeling with uninformative priors is used and estimates of the posterior distribution of age at onset and susceptibility parameters of interest have been obtained using Bayesian Markov chain Monte Carlo (MCMC) methods with OpenBugs program. A simulation study confirms that we obtain posterior estimates of the model parameters on shared and genetic variance components of age at onset and susceptibility with good coverage rates. Further, we analyze familial aggregation of diabetic nephropathy (DN) in large Finnish cohort of 528 sibships with type 1 diabetes (T1D). According to the variance components estimated a substantial familial variation in the susceptibility to DN exist among families, while time to DN is less influenced by shared familial factors.
[show abstract][hide abstract] ABSTRACT: The aim of this study was to examine the incidence and trends of type 1 and type 2 diabetes in the 15-39 year-old population between 1992 and 1996 in Finland.
Data on the nationwide incidence of diabetes were obtained from four data sources: standardised reports from diabetes nurses, the Finnish National Hospital Discharge Register, the Drug Reimbursement Register and the Drug Prescription Register. The inclusion criterion was consistency in the diagnosis of diabetes across at least two data sources. The sex- and age-specific incidence was calculated for 5-year age groups, both for type 1 and type 2 diabetes. The effects of age, sex and year of diagnosis were assessed by fitting the linear regression model to the incidence data.
Between 1992 and 1996 the age-adjusted incidence of type 1 diabetes among 15-39 year olds was 15.9 per 100,000/year. The incidence was highest among the 15-19 year olds and decreased with age. Conversely, the incidence of type 2 diabetes was very low among 15-19 year olds and increased with age. The total age-adjusted incidence of type 2 diabetes among 15-39 year olds was 11.8 per 100,000/year. The average annual increase in the incidence of type 2 diabetes was 7.9% (95% CI 3.7-12.2%).
The age at which the Finnish population is at risk of type 1 diabetes extends into young adulthood. The rapid increase in the incidence of type 2 diabetes in the young adult population is a current public health problem.
[show abstract][hide abstract] ABSTRACT: Several epidemiologic studies have shown an association between calcium and magnesium and coronary heart disease mortality and morbidity. In this small-area study, we examined the relationship between acute myocardial infarction (AMI) risk and content of Ca, Mg, and chromium in local groundwater in Finnish rural areas using Bayesian modeling and geospatial data aggregated into 10 km times symbol 10 km grid cells. Data on 14,495 men 35-74 years of age with their first AMI in the years 1983, 1988, or 1993 were pooled. Geochemical data consisted of 4,300 measurements of each element in local groundwater. The median concentrations of Mg, Ca, and Cr and the Ca:Mg ratio in well water were 2.61 mg/L, 12.23 mg/L, 0.27 microg/L, and 5.39, respectively. Each 1 mg/L increment in Mg level decreased the AMI risk by 4.9%, whereas a one unit increment in the Ca:Mg ratio increased the risk by 3.1%. Ca and Cr did not show any statistically significant effect on the incidence and spatial variation of AMI. Results of this study with specific Bayesian statistical analysis support earlier findings of a protective role of Mg and low Ca:Mg ratio against coronary heart disease but do not support the earlier hypothesis of a protective role of Ca.
Environmental Health Perspectives 06/2006; 114(5):730-4. · 7.26 Impact Factor
[show abstract][hide abstract] ABSTRACT: Bayesian spatial modeling has become important in disease mapping and has also been suggested as a useful tool in genetic fine mapping. We have implemented the Potts model and applied it to the Genetic Analysis Workshop 14 (GAW14) simulated data. Because the "answers" were known we have analyzed latent phenotype P1-related observed phenotypes affection status (genetically determined) and i (random) in the Danacaa population replicate 2. Analysis of the microsatellite/single-nucleotide polymorphism-based haplotypes at chromosomes 1 and 3 failed to identify multiple clusters of haplotype effects. However, the analysis of separately simulated data with postulated differences in the effects of the two clusters has yielded clear estimated division into the two clusters, demonstrating the correctness of the algorithm. Although we could not clearly identify the disease-related and the non-associated groups of haplotypes, results of both GAW14 and our own simulation encourage us to improve the efficiency and sensitivity of the estimation algorithm and to further compare the proposed method with more traditional methods.
[show abstract][hide abstract] ABSTRACT: Childhood diabetes is one of the major non-communicable diseases in children under 15 years of age. It requires a life-long insulin treatment and may lead to serious complications. Along with the worldwide increase in the incidence several countries have recently reported a decreasing trend in the age of onset of the disease. The aim of this study is to analyse long-term data on the incidence of the childhood diabetes in Finland from the birth cohorts perspective. The annual incidence data were available for the period 1965--1996 which translates into 1951--1996 birth cohorts. Hence the data consist of completely and partially observed cohorts. Bayesian modelling was employed in the analysis. Several different priors and cohort combinations were tried in order to determine the sensitivity of the results. The cumulative birth cohort incidence of diabetes was determined to have an increasing average annual trend of 2.5 per cent. Although the average birth cohort-specific age of onset was estimated to have decreased slightly over the years of observation, the trend could be a result of random variation.
Statistics in Medicine 11/2005; 24(19):2989-3004. · 2.04 Impact Factor