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Karri Silventoinen

Publications and source records attributed to Karri Silventoinen.

At least 19 recordsLinked to original sources
PubMed2026

Robust inference and correlates from genetic associations with personality.

Personality traits describe stable differences in how people think, feel and behave, and how they interact with and experience their social and physical environments1,2. Many questions remain unanswered about associations between DNA and personality traits, such as their robustness, their generalizability and the biological and social pathways through which they act. Here we meta-analyse data across 46 cohorts comprising 611,037 to 1.14 million participants with European-like and African-like genomes for genome-wide association studies (GWAS) of the Big Five personality traits (extraversion, agreeableness, conscientiousness, neuroticism and openness to experience), and data from up to 50,725 participants for within-family GWAS. We identify 1,260 lead genetic variants associated with personality, including 824 novel variants3. Common genetic variants explain a moderate 4.8-9.3% of the variance in measures of each trait, and 9.3-13.3% among instruments with typical measurement reliability. Genetic associations with personality are highly consistent but not identical across geography, reporter (self versus close other), age group and measurement instrument, and we find minimal spousal assortment for personality in recent history. In contrast to many other social and behavioural traits4,5, within-family GWAS and polygenic index analyses indicate that genetic associations with personality are minimally confounded by the shared family environment. Polygenic prediction, genetic correlation and Mendelian randomization analyses indicate that personality traits have widespread, potentially causal associations with consequential behaviours and life outcomes. Overall, we find that the genetic architecture of personality is robustly generalizable, minimally confounded and widely relevant to human experience.

Journal Article↗
PubMed2006

Association between height and coronary heart disease mortality: a prospective study of 35,000 twin pairs.

An inverse association between height and risk of coronary heart disease (CHD) is well demonstrated, but it is not known whether this association is because of genetic factors, socioeconomic background, or other environmental factors. Four population-based twin cohorts with register-based follow-up data on CHD mortality from Denmark (1966-1996), Finland (1975-2001), and Sweden (1963-2001 and 1972-2001) were used to investigate this question; response rates varied between 65% and 86%. Together, the cohorts included 74,704 twin individuals (35,042 complete twin pairs) with 5,943 CHD deaths during 1.99 million person-years of follow-up. Cox and conditional logistic regression models were used. Per 1-standard deviation decrease in height, height was inversely associated with CHD mortality in men (hazard ratio = 1.08, 95% confidence interval (CI): 1.04, 1.12) and in women (hazard ratio = 1.06, 95% CI: 1.01, 1.10). A twin who had died from CHD was on average shorter than the co-twin within monozygotic pairs (odds ratio = 1.27, 95% CI: 1.12, 1.44, with no sex difference), whereas a weaker association was found within dizygotic pairs in men (odds ratio = 1.01, 95% CI: 0.91, 1.13) and in women (odds ratio = 1.14, 95% CI: 1.01, 1.28). The inverse association between height and CHD mortality found within monozygotic discordant twin pairs suggests that this association is because of environmental factors that directly affect height and CHD risk.

Body Height↗
PubMed2006

Mental health functioning (SF-36) and intentions to retire early among ageing municipal employees: the Helsinki Health Study.

AIMS: To examine the associations of mental health functioning with intentions to retire early among ageing municipal employees. METHODS: Cross-sectional survey data (n = 7,765) from the Helsinki Health Study in 2000, 2001, and 2002 were used. Intentions to retire early were sought with a question: "Have you considered retiring before normal retirement age?" The dependent variable was divided into three categories: 1 = no intentions to retire early; 2 = weak intentions; 3 = strong intentions. Mental health functioning was measured by the Short Form 36 (SF-36) mental component summary (MCS). Other variables included age, sex, physical health functioning (SF-36), limiting longstanding illness, socioeconomic status, and spouse's employment status. Multinomial regression analysis was used to examine the association of mental health functioning with intentions to retire early. RESULTS: Employees with the poorest mental health functioning were much more likely to report strong intentions to retire early (OR 6.09, 95% CI 4.97-7.47) than those with the best mental health functioning. Adjustments for physical health, socioeconomic status, and spouse's employment status did not substantially affect this association. CONCLUSIONS: The findings highlight the importance of mental health for intentions to retire early. Strategies aimed at keeping people at work for longer should emphasize the importance of mental well-being and the prevention of poor mental health. More evidence is needed on why mental problems among ageing baby-boomer employees are giving rise to increasing social consequences, although the overall prevalence of mental problems has not increased.

Adult↗
PubMed2006

Genetic architecture of smoking behavior: a study of Finnish adult twins.

Both genetic and environmental factors affect smoking initiation and maintenance, but less is known about the genetic architecture of various other smoking-related behaviors. The aim of this study is to examine the genetic architecture of smoking behavior in a large twin cohort. Questionnaires with an extensive smoking history section were mailed to same-sex adult twins of the Finnish twin cohort. The final study population included 2923 monozygotic and 6018 dizygotic twin pairs aged 24 to 88 years. Two-stage bivariate genetic modeling of age at initiation with amount smoked (less than 20 cigarettes per day vs. 20 or more) and age at initiation with smoking cessation was done by using the Mx statistical package. For men the heritability estimate for age at initiation was .59 (95% confidence interval [CI] .49-.69), for amount smoked .54 (95% CI .45-.62) and for smoking cessation .58 (95% CI .50-.65). For women the heritability estimates were .36 (95% CI .28-.43), .61 (95% CI .46-.70) and .50 (95% CI .39-.60), respectively. The genetic correlations between age at initiation and amount smoked or smoking cessation were at most .22 in magnitude, indicating that genetic influences in age at initiation accounted for at most about 4% of the genetic factors in amount smoked or in cessation. Genetic factors are important in amount smoked and smoking cessation and they are largely independent of genetic influences on age at initiation. This has implications for defining phenotypes in searches for genes underlying smoking behaviors.

Age Factors↗
PubMed2005

Leisure time, occupational, and commuting physical activity and the risk of stroke.

BACKGROUND AND PURPOSE: The role of physical activity, especially that of occupational and commuting physical activity, in the prediction of stroke risk is not properly established. We assessed the relationship of different types of physical activity with total and type-specific stroke risk. METHODS: We prospectively followed 47 721 Finnish subjects 25 to 64 years of age without a history of coronary heart disease, stroke, or cancer at baseline. Hazard ratios (HRs) for incident stroke were estimated for different levels of leisure time, occupational, and commuting physical activity. RESULTS: During a mean follow-up of 19.0 years, 2863 incident stroke events were ascertained. The multivariate-adjusted (age, sex, area, study year, body mass index, systolic blood pressure, cholesterol, education, smoking, alcohol consumption, diabetes, and other 2 types of physical activity) HRs associated with low, moderate, and high leisure time physical activity were 1.00, 0.86, and 0.74 (Ptrend<0.001) for total stroke, 1.00, 0.87, and 0.46 (Ptrend=0.011) for subarachnoid hemorrhage, 1.00, 0.77, and 0.63 (Ptrend=0.024) for intracerebral hemorrhage, and 1.00, 0.87, and 0.80 (Ptrend=0.001) for ischemic stroke, respectively. The multivariate-adjusted HRs associated with none, 1 to 29, and > or =30 minutes of active commuting were 1.00, 0.92, and 0.89 (Ptrend=0.043) for total stroke, and 1.00, 0.93, and 0.86 (Ptrend=0.028) for ischemic stroke, respectively. Occupational activity had a modest association with ischemic stroke in the multivariate analysis (Ptrend=0.046). CONCLUSIONS: A high level of leisure time physical activity reduces the risk of all subtypes of stroke. Daily active commuting also reduces the risk of ischemic stroke.

Adult↗
PubMed2005

Educational inequalities in the metabolic syndrome and coronary heart disease among middle-aged men and women.

BACKGROUND: Previous studies have shown socioeconomic inequalities in the metabolic syndrome and coronary heart disease (CHD), but it is not known whether educational disparities in the metabolic syndrome explain educational inequalities in CHD. We investigated this question in a prospective study of middle-aged men and women. METHODS: Baseline data were collected in 1992 in Finland from 864 men and 1045 women aged 45-64 years without history of CHD. A total of 113 new CHD cases were identified by the end of 2001. Logistic and Cox regression models were used in data analysis. RESULTS: The metabolic syndrome defined by NCEP criteria was less prevalent in subjects with university education (21% in men and 14% in women) compared with basic level education (41% and 27%, respectively). Adjusting for health behavioural factors had only a slight effect on the educational gradient in the metabolic syndrome. An educational gradient in CHD incidence was clear [hazard ratio (HR) = 0.67 95% confidence interval (CI) 0.48-0.94, men and women combined]. Adjustment for the metabolic syndrome attenuated this gradient only slightly, but when individual components of the metabolic syndrome were included as covariates the attenuation was more substantial (HR = 0.73 95% CI 0.52-1.04). CONCLUSIONS: Educational differences in the metabolic syndrome and CHD incidence are clear. Metabolic risk factors explain the gradient in CHD incidence partly, but only when they are treated as independent risk factors. Screening for the metabolic syndrome alone is not sufficient to account for socioeconomic inequalities in cardiovascular disease.

Coronary Disease↗
PubMed2005

The validity of the Finnish Diabetes Risk Score for the prediction of the incidence of coronary heart disease and stroke, and total mortality.

BACKGROUND: Cardiovascular disease shares several risk factors with type 2 diabetes. We tested whether the Finnish Diabetes Risk Score (FINDRISC), recently developed in a Finnish population to estimate the future risk of diabetes, would also identify individuals at high risk of coronary heart disease (CHD) and stroke, and total mortality in this same population. DESIGN: Independent risk factor surveys were conducted in 1987, 1992, and 1997 in Finland, comprising 8268 men and 9457 women aged 25-64 years and free of CHD and stroke at baseline. During the follow-up until the end of 2001, 699 incident acute CHD events, 324 acute stroke events, and 765 deaths occurred. METHODS: The data were analysed by using receiver operating characteristic (ROC) curves and the Cox-regression model. RESULTS: The areas under the ROC curves (AUC) were 71% for CHD, 73% for stroke, and 68% for total mortality in men and 78, 68, and 72% in women, respectively. The addition of systolic and diastolic blood pressures, total and high-density lipoprotein cholesterol, and smoking increased the AUC values modestly (the change of the absolute values from 2.6 to 6.5%), but the additional use of plasma glucose had only a slight effect on the AUC values for CHD and stroke. CONCLUSIONS: The FINDRISC is a reasonably good predictor of CHD, stroke and total mortality.

Adult↗
PubMed2004

Physical activity, body mass index, and risk of type 2 diabetes in patients with normal or impaired glucose regulation.

BACKGROUND: Sedentary lifestyle, obesity, and impaired glucose regulation are associated with the risk of type 2 diabetes. However, the joint associations of these risk factors are not known. METHODS: We prospectively followed up 2017 Finnish men and 2352 Finnish women aged between 45 and 64 years without a history of known or newly diagnosed diabetes at baseline. Single and joint associations of physical activity, body mass index (BMI), and blood glucose levels with risk of type 2 diabetes were examined using Cox proportional hazards models. RESULTS: During a mean follow-up of 9.4 years, there were 120 incident cases of type 2 diabetes. After adjustment for confounding factors (age, study year, sex, systolic blood pressure, smoking, and education), physical activity was found to be inversely associated with the risk of type 2 diabetes. This association was persistent in subjects with (1) both obesity and impaired glucose regulation, (2) either obesity or impaired glucose regulation, and (3) a normal BMI and glucose regulation. Similarly, the multivariate-adjusted positive association between BMI and risk of type 2 diabetes was consistently observed. Obesity in subjects who reported being inactive and had normal glucose levels was associated with an increased risk of diabetes compared with a normal BMI in subjects who reported being active and had impaired glucose regulation. CONCLUSIONS: Increasing physical activity can reduce the risk of type 2 diabetes. The protective effect of physical activity was observed in subjects with an excessive BMI and elevated glucose levels. Physical activity and weight control are critical factors in diabetes prevention in subjects with both normal and impaired blood glucose regulation.

Blood Glucose↗
PubMed2004

Joint effects of physical activity, body mass index, waist circumference and waist-to-hip ratio with the risk of cardiovascular disease among middle-aged Finnish men and women.

AIMS: To assess joint associations of physical activity and different indicators of obesity (body mass index, waist circumference, and waist-to-hip ratio) with the risk of cardiovascular disease (CVD). METHODS AND RESULTS: The study comprised 18,892 Finnish men and women aged 25-74 years without history of coronary heart disease, stroke, or heart failure at baseline. Physical activity, different indicators of obesity, education, smoking, blood pressure, total and high-density lipoprotein cholesterol and history of diabetes were measured at baseline. An incident CVD event was defined as the first stroke or coronary heart disease event or CVD death based on national hospital discharge and mortality register data. The median follow-up time was 9.8 years. Physical activity had a strong, independent, and inverse association with CVD risk in both genders. All obesity indicators had a significant direct association with CVD risk after adjustment for age, smoking, education and physical activity. Further adjustment for the obesity-related risk factors weakened the associations and they remained statistically significant in men only. Physical activity and the obesity indicators both predicted CVD risk in men, but in women the joint effect was inconsistent. CONCLUSION: Both regular physical activity and normal weight can reduce the risk of CVD. Physical inactivity seems to have an independent effect on CVD risk, whereas obesity increases the risk partly through the modification of other risk factors.

Adult↗
PubMed2004

Smoking cessation by socioeconomic status and marital status: the contribution of smoking behavior and family background.

We studied socioeconomic status and marital status as predictors of smoking cessation, adjusting for previous smoking behavior and family background by using a large Finnish prospective twin dataset unselected for smoking behavior. The data were collected by postal surveys in 1981 and 1990, and the sample comprised 3,069 current smokers, of whom 20% had quit smoking by 1990. Logistic regression analyses of all twin individuals and conditional logistic regression analysis of discordant pairs were used to predict smoking cessation. High education predicted smoking cessation among both men (OR=2.32, 95% CI=1.31-4.10) and women (OR=3.98, 95% CI=1.85-8.51) as did high social class among women. Additionally, starting at a late age, smoking a small number of cigarettes per day, and a low level of nicotine per cigarette predicted cessation. Socioeconomic differences in cessation diminished only slightly when we adjusted for smoking behavior factors. Among the twin pairs who were discordant in terms of smoking cessation, the twin who continued smoking also smoked more on average at baseline (men: OR=.94, 95% CI=.89-.99; women: OR=.82, 95% CI=.71-.94). The male twins who continued smoking had a smaller probability of getting married during the follow-up than had the cotwin who had quit smoking (OR=3.91, 95% CI=1.02-15.02). Indicators of socioeconomic status were important predictors of smoking cessation even when we adjusted for previous smoking behavior. For men, marriage was associated with an increased probability of cessation

Adolescent↗
PubMed2004

Effect of environmental and genetic factors on education-associated disparities in weight and weight gain: a study of Finnish adult twins.

BACKGROUND: Disparities in body mass index (BMI) between persons with different educational levels in Western countries are well documented, but the background of these education-associated disparities remains poorly understood. OBJECTIVE: The objective was to examine the influence of environmental and genetic factors on education-associated disparities in self-reported BMI and weight change. DESIGN: Longitudinal postal surveys were performed in 1975, 1981, and 1990. The data were analyzed by using multivariate genetic models for twin data. The data derived from the Finnish Twin Cohort included 2482 monozygotic and 5113 dizygotic same-sex male and female twin pairs born between 1915 and 1957. RESULTS: Education-associated differences in BMI and in weight change were clear in 1975 and 1981, respectively, whereas no differences were seen in weight change between 1981 and 1990 when age and baseline BMI were adjusted for. The trait correlation between baseline BMI and educational attainment (-0.15 in men and women) was mainly due to correlations between additive genetic factors that contributed to BMI and education in men (-0.20; 95% CI: -0.25, -0.14) and women (-0.32; 95% CI: -0.40, -0.25) when adjusted for age. Among women, a weaker positive correlation was found for the unshared environmental effects contributing to the 2 traits (0.06; 95% CI: 0.02, 0.12). The same factors that affected the association between education and BMI in 1975 largely explained the association between education and weight change in 1981. CONCLUSION: The results suggest the possibility that common genetic factors affect educational attainment and body weight, which contribute to education-associated disparities in BMI in adulthood.

Adult↗
PubMed2004

Factors contributing to sense of coherence among men and women.

BACKGROUND: The purpose of this study was to examine the associations of four key areas of resistance resources (GRR), i.e. childhood living conditions, work and family life, and social relationships, with sense of coherence (SOC) among Finnish men and women. A particular interest was devoted to interactions between sex and GRR. METHODS: The data derived from a representative personal interview survey collected by Statistics Finland in 1994 (N=8650, response rate 73%). This study included ages 25-64 (N=6506, 49% women). The associations of age, educational attainment, childhood living conditions, work and family, and social relationships with SOC were analysed using ordinary regression analysis. RESULTS: Among both men and women, psycho-emotional resources rather than socio-economic circumstances were associated with SOC. These resources included the quality of the relationship with partner, social support, quality of work, and childhood living conditions. Although sex differences were small, the association of living without a partner with low SOC was stronger among men than women. CONCLUSION: SOC is strongly associated with the psycho-emotional resistance resources. In the Finnish context, the SOC scale was largely sex neutral.

Adaptation, Psychological↗
PubMed2004

gamma-Glutamyltransferase, obesity, and the risk of type 2 diabetes: observational cohort study among 20,158 middle-aged men and women.

Serum gamma-glutamyltransferase (GGT) concentration within its normal range has emerged as an important predictor in the pathogenesis of diabetes. We studied serum GGT as a predictor of type 2 diabetes incidence and a possible interaction between obesity and GGT on the development of type 2 diabetes in men and women. A prospective cohort study of 20,158 Finnish men and women aged 25-64 yr who participated in cardiovascular risk-factor surveys carried out in four areas during 10 yr. The average follow-up time was 12.7 yr, and there were 388 incident diabetes cases. Serum GGT cut points were at the 25th, 50th, 75th, and 90th percentiles. Initiation of new diabetes medication defined incidence cases. After adjustment for known risk factors of type 2 diabetes, relative risks for incident diabetes across GGT categories were 1.0, 1.2, 2.3, 3.1, and 3.9 among men and 1.0, 0.8, 1.7, 3.5, and 6.4 among women (P for trend < 0.01, respectively). Body mass index appeared to be more strongly associated with type 2 diabetes in both men and women over age 50 yr with GGT median or greater, compared with subjects with GGT less than median. In conclusion, in women as well as men, serum GGT level within its normal range predicted type 2 diabetes and may modify the well-known association between body mass index and type 2 diabetes.

Adult↗
PubMed2004

Relative weight and income at different levels of socioeconomic status.

OBJECTIVES: We examined the association of relative weight with individual income at different levels of socioeconomic status among gainfully employed Finnish women and men. METHODS: We used a population-based survey including 2068 women and 2314 men with linked income data from a taxation register. Regression analysis was used to calculate mean income levels within educational and occupational groups. RESULTS: Compared with their normal-weight counterparts, obese women with higher education or in upper white-collar positions had significantly lower income; a smaller income disadvantage was seen in overweight women with secondary education and in manual workers. Excess body weight was not associated with income disadvantages in men. CONCLUSIONS: Obesity is associated with a clear income disadvantage, particularly among women with higher socioeconomic status.

Adult↗
PubMed2003

Determinants of variation in adult body height.

Final body height is achieved as the result of a combination of genetic and environmental factors. The aim of this article is to review past studies on body height that have followed different scientific traditions. In modern Western societies, about 20% of variation in body height is due to environmental variation. In poorer environments, this proportion is probably larger, with lower heritability of body height as well as larger socioeconomic body height differences. The role of childhood environment is seen in the increase in body height during the 20th century simultaneously with the increase in the standard of living. The most important non-genetic factors affecting growth and adult body height are nutrition and diseases. Short stature is associated with poorer education and lower social position in adulthood. This is mainly due to family background, but other environmental factors in childhood also contribute to this association. Body height is a good indicator of childhood living conditions, not only in developing countries but also in modern Western societies. Future studies combining different scientific traditions in auxology are needed to create a more holistic view of body height.

Adolescent↗
PubMed2003

Appropriateness of anthropometric obesity indicators in assessment of coronary heart disease risk among Finnish men and women.

AIMS: The aim of the study was to compare the appropriateness of different obesity indicators in the assessment of coronary heart disease (CHD) risk. METHODS: The study cohort included 11,510 Finnish men and women aged 25 to 64 year at baseline who participated in a cardiovascular disease risk factor survey in 1987 or 1992. At baseline, data on smoking and diabetes were recorded, blood pressure. body mass index (BMI), waist circumference (WC), and waist to hip ratio (WHR) were measured, and serum total and high-density lipoprotein (HDL) cholesterol were determined. A follow-up was done to the end of 1997. Death or diagnosed event from CHD was used as an outcome variable. RESULTS: At baseline, BMI was the best explaining variable for systolic and diastolic blood pressure (DBP) and for total cholesterol, whereas WC was the best explaining variable for HDL cholesterol, among both men and women. During the follow-up, WHR was the best predictor of CHD incidence. However, after the adjustment for other CHD risk factors none of the obesity indicators remained statistically significant. In both sexes, BMI was a statistically significant predictor of CHD incidence among subjects with DBP lower than the mean. Among men, a similar interaction was seen between DBP and WC. CONCLUSION: WHR was the best predictor of CHD incidence in our data. Abdominal obesity has an effect on CHD incidence independently of general obesity.

Adult↗
PubMed2003

The association between body height and coronary heart disease among Finnish twins and singletons.

OBJECTIVE: An inverse association between body height and the incidence of coronary heart disease (CHD) has been observed. However, the mechanisms behind this association are still largely unknown. We will examine the role of genetic and familial factors behind the association in a large twin data set. DESIGN AND SETTING: The data were derived from the Finnish Twin cohort including 2438 singletons, 4073 monozygotic (MZ) twins, and 9202 dizygotic (DZ) twins aged 25-69 years at baseline in 1976. Incident CHD cases were derived from hospital discharge data and cause of death data between 1977 and 1995. Cox regression analysis and conditional logistic regression analysis were used. RESULTS: In population-level analyses no differences in the general risk of CHD between zygosity groups were found. The association between body height and CHD was similar between sexes and zygosity groups. When men and women in all zygosity groups were studied together an increased risk of CHD was found only among the shortest quartile (hazard ratio [HR] = 1.34, 95% CI: 1.14-1.57). Among the twin pairs discordant for CHD a suggestive increased risk for the shorter twin was seen among DZ twins (odds ratio [OR] = 1.19, 95% CI: 0.95-1.48) when men and women were studied together. CONCLUSION: An inverse association between body height and CHD was broadly similar between sexes and twin zygosity groups and was associated with short stature. Among discordant twin pairs we found a weak association among DZ twins but not MZ twins. This may suggest the role of genetic liability behind the association between body height and CHD.

Adult↗