Dietary Saturated Fat and Bone Health in Young Adults: The Young Finns Cohort.

Previous studies suggest that saturated fat (SFA) intake may negatively impact on bone. However, few human studies on the topic exist. Women and men aged 31-46 years from the Cardiovascular Risk in Young Finns study attended the peripheral quantitative computed tomography and ultrasound bone measurements in 2008 (n = 1884-1953, ~ 56% women). In addition, fracture diagnoses in 1980-2018 were searched for the national health care registers and 431 participants had at least one fracture. Food consumption was gathered with the 48-h dietary recall interviews and food frequency questionnaire in 1980-2007. In the present study, radial, tibial, and calcaneal bone traits, and fractures were examined relative to the long-term intake of SFA. No consistent associations were seen between bone outcomes and SFA intake that would have replicated in both women and men. The only evidence for differential distributions was seen in cortical density and cortical-to-total area ratio at the radial shaft, and speed of sound at the calcaneus, which were 0.1-0.4% higher in women in the lowest tertile of SFA intake compared with the highest tertile. In addition, among men, the odds ratio (OR) of fractures was greater in the second (OR 1.86, 95% confidence interval (CI) 1.03-3.33) and third tertile of SFA intake (OR 2.45, 95% CI 1.38-4.36) compared with the lowest tertile, independently of many risk factors of osteoporosis. In this observational study, we found no robust evidence of the associations of dietary long-term SFA intake with bone outcomes. Therefore, additional studies are needed to confirm the association of dietary SFA with bone health in humans.

Childhood Oral Infections Associate with Adulthood Metabolic Syndrome: A Longitudinal Cohort Study.

Chronic oral infection/inflammation is cross-sectionally associated with metabolic syndrome (MetS) in adults, but there are few longitudinal studies and studies on childhood oral infections and adult MetS risk. We investigated whether childhood clinical parameters indicative of oral infection/inflammation were associated with adulthood MetS and its components. A total of 755 children aged 6, 9, and 12 y underwent a clinical oral examination in 1980 as part of the Cardiovascular Risk in Young Finns Study. Oral health measures included bleeding on probing (BOP), periodontal probing pocket depth, caries, fillings, and visible plaque. Metabolic parameters were determined at baseline and during follow-up. MetS was diagnosed (n = 588, 77.9%) in the adulthood at 21 y (in 2001), 27 y (in 2007), and 31 y (in 2011) after the oral assessment, when the participants were 27 to 43 y old. Regression analyses were adjusted for childhood age, sex, body mass index, and family income, as well as adulthood smoking and education level. In adulthood, MetS was diagnosed in 11.9% (2001), 18.7% (2007), and 20.7% (2011) of participants at the 3 follow-ups. Childhood caries and fillings were associated with increased risk of adult MetS (risk ratio [95% CI], 1.25 [0.90 to 2.45] and 1.27 [1.02 to 1.99]) and with increased systolic blood pressure (1.78 [1.01 to 4.26] and 2.48 [1.11 to 4.12]) and waist circumference (2.25 [1.02 to 4.99] and 1.56 [1.01 to 3.25]), whereas BOP and visible plaque were associated with plasma glucose (1.97 [1.08 to 3.60] and 1.88 [1.00 to 3.53]). Severity of BOP (P = 0.015) and caries (P = 0.005) and teeth with plaque (P = 0.027) were associated with number of MetS components. No such trends were seen with probing pocket depth. Childhood oral infection/inflammation was associated with adverse metabolic parameters and MetS in adulthood.

Increase in adiposity from childhood to adulthood predicts a metabolically obese phenotype in normal-weight adults.

Normal weight is associated with a favorable cardiometabolic risk profile and low risk of type 2 diabetes and cardiovascular disease. However, some normal-weight individuals-the "metabolically obese normal weight" (MONW)-show a cardiometabolic risk profile similar to the obese. Previous studies have shown that older age, central body fat distribution, and unfavorable lifestyle increase the risk of MONW. However, the role of early-life factors in MONW remains unknown. We examined the associations of early-life factors with adult MONW in 1178 individuals from the Cardiovascular Risk in Young Finns study who were followed up from childhood to adulthood. The strongest early predictor for adult MONW was an increase in BMI from childhood to adulthood (p = 3.1 × 10-11); each 1 SD increase in BMI z-score from childhood to adulthood led to a 2.56-fold increase in the risk of adult MONW (CI 95% = 1.94-3.38). Other significant predictors of adult MONW were male sex (OR = 2.38, 95% = 1.63-3.47, p = 7.0 × 10-6), higher childhood LDL cholesterol (OR = 1.41 per 1 SD increase in LDL cholesterol, CI 95% = 1.14-1.73, p = 0.001), and lower HDL cholesterol (OR = 1.51 per 1 SD decrease in HDL cholesterol, CI 95% = 1.23-1.85, p = 5.4 × 10-5). Our results suggest that an increase in adiposity from childhood to adulthood is detrimental to cardiometabolic health, even among individuals remaining normal weight.

Geographic origin as a determinant of left ventricular mass and diastolic function - the Cardiovascular Risk in Young Finns Study.

AIMS: Eastern Finns have higher risk of coronary heart disease (CHD) and carotid intima-media thickness than western Finns although current differences in CHD risk factors are minimal. Left ventricular (LV) mass and diastolic function predict future cardiovascular events but their east-west differences are unknown. We examined the association of eastern/western baseline origin with LV mass and diastolic function. METHODS: The study population included 2045 subjects of the Cardiovascular Risk in Young Finns Study with data from the baseline survey (1980) and the latest follow-up (2011) when echocardiography was performed at the age of 34-49 years. RESULTS: Subjects with eastern baseline origin had in 2011 higher LV mass (139±1.0 vs. 135±1.0 g, p=0.006) and E/e'-ratio indicating weaker LV diastolic function (4.86±0.03 vs. 4.74±0.03, p=0.02) than western subjects. Results were independent of age, sex, area of examination and CHD risk factors such as blood pressure and BMI (LV mass indexed with height: p<0.0001; E/e'-ratio: p=0.01). LV end-diastolic volume was higher among subjects with eastern baseline origin (135±0.9 vs. 131±0.9 ml, p=0.0011) but left atrial end-systolic volume, also indicating LV diastolic function, was not different between eastern and western subjects (43.4±0.5 vs. 44.0±0.5 ml, p=0.45). Most of the subjects were well within the normal limits of these echocardiographic measurements. CONCLUSIONS: In our healthy middle-aged population, geographic origin in eastern Finland associated with higher LV mass compared to western Finland. Higher E/e'-ratio suggests that subjects with eastern baseline origin might have higher prevalence of diastolic dysfunction in the future than western subjects.

Longitudinal physical activity trajectories from childhood to adulthood and their determinants: The Young Finns Study.

Determining lifelong physical activity (PA) trajectories and their determinants is essential to promote a physically active lifestyle throughout the life-course. We aimed to identify PA trajectories from childhood to midlife and their determinants in a longitudinal population-based cohort. This study is a part of the Cardiovascular Risk in Young Finns Study. From 1980, a population-based cohort (N = 3596; 1764 boys/1832 girls, age 3-18 years) has been followed up for 31 years. PA indices were formed based on self-reported data (between age 9-49 years) on frequency, duration, and intensity of leisure (during childhood) or high-intensity (at later age) PA and on sports club participation/competitions. PA trajectories were analyzed using group-based trajectory modeling. Childhood (age 12 years), young adulthood (age 24 years), and early midlife (age 37 years) determinants were analyzed. Five PA trajectories were identified: persistently active (6.6%), decreasingly active (13.9%), increasingly active (13.5%), persistently low active (51.4%, reference group), persistently inactive (14.6%). In childhood, rural residential area (OR 0.45, 95% CI 0.21-0.96) and high academic performance (OR 2.18; 95% CI 1.58-3.00) associated with persistently active group. In early midlife, smoking (OR 1.66; 95% CI 1.07-2.58) associated with persistently inactive group, regular alcohol drinking (OR 2.91; 95% CI 1.12-7.55) with persistently active group and having children (OR 2.07; 95% CI 1.27-3.38) with decreasingly active group. High adulthood education associated with both decreasingly (OR 1.87; 95% CI 1.05-3.35) and increasingly (OR 2.09; 95% CI 1.19-3.68) active groups. We identified five PA trajectories from childhood into midlife. Most prominent determinants were academic achievement, education, having children and health habits (i.e. smoking/alcohol use).

Education as a moderator of genetic risk for higher body mass index: prospective cohort study from childhood to adulthood.

OBJECTIVES: The life-course development of body mass index (BMI) may be driven by interactions between genes and obesity-inducing social environments. We examined whether lower parental or own education accentuates the genetic risk for higher BMI over the life course, and whether diet and physical activity account for the educational differences in genetic associations with BMI. SUBJECTS/METHODS: The study comprised 2441 participants (1319 women, 3-18 years at baseline) from the prospective, population-based Cardiovascular Risk in Young Finns Study. BMI (kg/m2) trajectories were calculated from 18 to 49 years, using data from six time points spanning 31 years. A polygenic risk score for BMI was calculated as a weighted sum of risk alleles in 97 single-nucleotide polymorphisms. Education was assessed via self-reports, measured prospectively from participants in adulthood and from parents when participants were children. Diet and physical activity were self-reported in adulthood. RESULTS: Mean BMI increased from 22.6 to 26.6 kg/m2 during the follow-up. In growth curve analyses, the genetic risk score was associated with faster BMI increase over time (b=0.02, (95% CI, 0.01-0.02, P<0.001)). The association between the genetic risk score and BMI was more pronounced among those with lower educational level in adulthood (b=-0.12 (95% CI, -0.23-0.01); P=0.036)). No interaction effect was observed between the genetic risk score and parental education (b=0.05 (95% CI, -0.09-0.18; P=0.51)). Diet and physical activity explained little of the interaction effect between the genetic risk score and adulthood education. CONCLUSIONS: In this prospective study, the association of a risk score of 97 genetic variants with BMI was stronger among those with low compared with high education. This suggests lower education in adulthood accentuates the risk of higher BMI in people at genetic risk.

Early work-related physical exposures and low back pain in midlife: the Cardiovascular Risk in Young Finns Study.

OBJECTIVE: To examine whether heavy physical workload in young adulthood increases the risk of local and radiating low back pain (LBP) in midlife. METHODS: Longitudinal nationally representative Young Finns Study data among women (n=414) and men (n=324), aged 18-24 years in 1986 (baseline), were used. Physical heaviness of work was reported at baseline and follow-up (2007), and local and radiating LBP at follow-up. Covariates were age, smoking and body mass index. Logistic regression was used to examine the associations between physical heaviness of work and LBP. Additionally, the mediating effect of back pain at baseline was examined (the Sobel test). RESULTS: After adjustment for the covariates, and as compared with sedentary/light physical workload, heavy physical workload was associated with radiating LBP among women (OR 4.09, 95% CI 1.62 to 10.31) and men (OR 2.01, 95% CI 1.06 to 3.82). Among men, early back pain mediated the association (p value from the Sobel test=0.006). Among women, early exposure to physically heavy work showed the most consistent associations, while early and late exposures were associated with radiating and local LBP among men. Persistently heavy physical work was associated with radiating LBP among women and men. CONCLUSIONS: Physically heavy work at a young age can have a long-lasting effect on the risk of LBP, radiating LBP in particular. These results highlight the need to consider early and persistent exposures to prevent the adverse consequences of physical workload for the low back.

Longitudinal investigation of adenovirus 36 seropositivity and human obesity: the Cardiovascular Risk in Young Finns Study.

BACKGROUND/OBJECTIVES: Adenovirus-36 (Adv-36) infection is associated with exaggerated adipogenesis in cell culture and the development of obesity in animal models and humans, but a causal relationship remains unproven. Our objective was to determine whether serological evidence of Adv-36 infection in childhood and/or adulthood is associated with adult obesity. SUBJECTS/METHODS: Paired plasma concentrations of Adv-36 antibodies were measured by a novel enzyme-linked immunosorbent assay in a subgroup (n=449) of the Cardiovascular Risk in Young Finns Study in childhood (mean age 11.9 years) and adulthood (mean age 41.3 years). The study group included (1) individuals who had maintained normal-weight status (2) those who became obese adults from a normal-weight status in childhood and (3) those that were overweight/obese as a child and obese as an adult. RESULTS: Mean (s.d.) time between baseline and follow-up was 29.4 (3.2) years (range 21-31 years). A total of 24.4% of individuals who were normal weight throughout life were seropositive for Adv-36 during child and/or adulthood as compared with 32.3% of those who became obese adults (P=0.11). Those who became obese in adulthood were more likely to be Adv-36 seropositive as adults compared with those who maintained normal weight (21.3% vs. 11.6%, P=0.02). This difference was mediated by a decline in Adv-36 seropositivity between child and adulthood in those maintaining normal weight. No differences were observed in body mass index across the life course, nor in waist circumference in adult life, between those who were Adv-36 seronegative or seropositive at any age. CONCLUSIONS: Individuals who gained weight across the life course were more likely to be Adv-36 seropositive in adult life than those who did not gain weight. However, analysis of change in weight status in relation to Adv-36 positivity did not support a causal role for Adv-36 in the development of obesity.

Adolescence physical activity is associated with higher tibial pQCT bone values in adulthood after 28-years of follow-up--the Cardiovascular Risk in Young Finns Study.

High peak bone mass and strong bone phenotype are known to be partly explained by physical activity during growth but there are few prospective studies on this topic. In this 28-year follow-up of Cardiovascular Risk in Young Finns Study cohort, we assessed whether habitual childhood and adolescence physical activity or inactivity at the age of 3-18 years were associated with adult phenotype of weight-bearing tibia and the risk of low-energy fractures. Baseline physical activity and data on clinical, nutritional and lifestyle factors were assessed separately for females and males aged 3-6-years (N=395-421) and 9-18-years (N=923-965). At the age of 31-46-years, the prevalence of low-energy fractures was assessed with a questionnaire and several tibial traits were measured with pQCT (bone mineral content (BMC; mg), total and cortical cross-sectional areas (mm(2)), trabecular (for the distal site only) and cortical (for the shaft only) bone densities (mg/cm(3)), stress-strain index (SSI; mm(3), for the shaft only), bone strength index (BSI; mg(2)/cm(4), for the distal site only) and the cortical strength index (CSI, for the shaft only)). For the statistical analysis, each bone trait was categorized as below the cohort median or the median and above and the adjusted odds ratios (OR) were determined. In females, frequent physical activity at the age of 9-18-years was associated with higher adulthood values of BSI, total and cortical areas, BMC, CSI and SSI at the tibia independently of many health and lifestyle factors (ORs 0.33-0.53, P≤0.05; P-values for trend 0.002-0.05). Cortical density at the tibial shaft showed the opposite trend (P-value for trend 0.03). Similarly in males, frequent physical activity was associated with higher values of adult total and cortical areas and CSI at the tibia (ORs 0.48-0.53, P≤0.05; P-values for trend 0.01-0.02). However, there was no evidence that childhood or adolescence physical activity was associated with lower risk of low energy fractures during the follow-up. In conclusion, frequent habitual physical activity in adolescence seems to confer benefits on tibial bone size and geometry in adulthood.

High serum n6 fatty acid proportion is associated with lowered LDL oxidation and inflammation: the Cardiovascular Risk in Young Finns Study.

The intake of polyunsaturated fatty acids (PUFAs) is generally linked with a reduced cardiovascular disease (CVD) risk, but an elevated n6PUFA intake, without simultaneous n3PUFA supply, may elevate the risk. PUFAs are suspected as being easily oxidized and have a potential role in lipoprotein oxidation and inflammation. Saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) are resistant to oxidation. However, in a Western diet, their most important source is red meat, a food stuff rich in heme iron which can catalyze oxidative reactions. Therefore, different serum fatty acid (FA) proportions (free + esterified) were correlated with the status of low-density lipoprotein (LDL) oxidation in vivo (conjugated dienes = oxLDLlipids and antibody-based oxidized proteins = oxLDLprot) and inflammation (serum CRP) in 2196 Finnish subjects (age: 24-39 years) using CVD risk factor-adjusted linear regression models. High n6PUFA, PUFA/SFA and n6/n3 ratios, and low SFA and MUFA were all associated with reduced levels of oxLDLlipids, oxLDLprot, and CRP. These findings at the population level suggest that PUFAs are negatively and SFAs and MUFAs positively related with LDL oxidation and inflammation; these conclusions are in line with previous observations linking PUFAs, particularly n6PUFAs, with lower CVD risk, and SFAs with increased risk.

Depressive symptoms are associated with lower bone mineral density in young adults with high job strain. The Cardiovascular Risk in Young Finns Study.

BACKGROUND: Job strain has been associated with depressive symptoms, and depression has been associated with low bone mineral density (BMD). PURPOSE: The associations between BMD and job strain have not been studied. We examined the relations between BMD, job strain, and depressive symptoms in a population-based group of young adults in Finland. METHOD: Ultrasonic measurement of BMD at the calcaneus was performed on 777 participants (men 45 %, aged 30-45) drawn from the Cardiovascular Risk in Young Finns Study. Job strain was assessed by self-administered questionnaires by the combination of job demands and job control. Depressive symptoms were assessed with a modified Beck Depression Inventory. The effects of job strain on BMD were studied with multivariable analyses with age, sex, BMI, vitamin D, and calcium intake, physical activity, cigarette smoking, alcohol use, and depressive symptoms as covariates. RESULTS: Depressive symptoms were independently associated with lower BMD T score in participants with high job strain (ß = -0.241, p = 0.02), but depressive symptoms were not significantly associated with BMD in the low (ß = -0.160, p = 0.26) and intermediate (ß = -0.042, p = 0.66) job strain categories. CONCLUSION: The results suggest that job strain modifies the association between depressive symptoms and BMD. Depressed individuals with high work-related stress might be in increased risk of lower bone mineral density.

Childhood and adult socio-economic position and social mobility as determinants of low back pain outcomes.

BACKGROUND: Low back pain (LBP) is a prevalent problem and tends to be socio-economically patterned. Relatively little is known about life-course socio-economic circumstances as determinants of different types of LBP. Our aim was to examine whether childhood and adult socio-economic position and social mobility are associated with radiating and non-specific LBP and sciatica. METHOD: Data were derived from the Young Finns Study (n = 2231). Childhood socio-economic position was based on parental education, occupational class and family income at baseline in 1980. Data on own education and LBP outcomes were collected at the end of follow-up in 2007. Social mobility was based on parental and own education. Covariates were composed of age, parental body mass index and smoking. RESULTS: Both childhood and own socio-economic position remained associated with radiating LBP and sciatica after adjustments. However, the associations varied by socio-economic indicator and gender. Stable lower socio-economic position and downward mobility were associated with radiating LBP. CONCLUSION: Childhood socio-economic circumstances affect the risk of radiating LBP and sciatica in adulthood. To prevent low back disorders, early socio-economic circumstances need to be considered alongside own socio-economic position.

Sedentary behaviours and obesity in adults: the Cardiovascular Risk in Young Finns Study.

OBJECTIVE: Sedentary behaviour may contribute to the development of obesity. We investigated the relations between different types of sedentary behaviour and adiposity markers in a well-characterised adult population after controlling for a wide range of potential confounders. DESIGN: Cross-sectional study. SETTING: The Cardiovascular Risk in Young Finns Multicenter Study. Participants Sedentary time (TV viewing, computer time, reading, music/radio listening and other relaxation) was assessed with a questionnaire for 1084 women and 909 men aged 30-45 years. Other study variables included occupational and leisure-time physical activity, sleep duration, socioeconomic status, smoking, alcohol consumption, energy intake, adherence to the recommended diet, multiple individual food items, age and genetic variants associated with body mass index (BMI). Primary outcome measures BMI in kg/m(2) and waist circumference (WC in cm). RESULTS: Of the different sedentary behaviour types, TV viewing was most consistently related to higher BMI and WC, both in men and women. One additional daily TV hour was associated with a 1.81±0.44 cm larger WC in women and 2 cm±0.44 cm in men (both p<0.0001). The association with TV was diluted, but remained highly significant after adjustments with all measured covariates, including several potentially obesogenic food items associated with TV viewing. The intakes of food items such as sausage, beer and soft drinks were directly associated with TV viewing, while the intakes of oat and barley, fish, and fruits and berries were associated indirectly. After these adjustments, non-TV sedentary behaviour remained associated with adiposity indices only in women. CONCLUSIONS: Out of the different types of sedentary behaviour, TV viewing was most consistently associated with adiposity markers in adults. Partial dilution of these associations after adjustments for covariates suggests that the obesogenic effects of TV viewing are partly mediated by other lifestyle factors.

Triglyceride-cholesterol imbalance across lipoprotein subclasses predicts diabetic kidney disease and mortality in type 1 diabetes: the FinnDiane Study.

BACKGROUND: Circulating cholesterol (C) and triglyceride (TG) levels are associated with vascular injury in type 1 diabetes (T1DM). Lipoproteins are responsible for transporting lipids, and alterations in their subclass distributions may partly explain the increased mortality in individuals with T1DM. DESIGN AND SUBJECTS: A cohort of 3544 individuals with T1DM was recruited by the nationwide multicentre FinnDiane Study Group. At baseline, six very low-density lipoprotein VLDL, one intermediate-density lipoprotein IDL, three low-density lipoprotein LDL and four higher high-density lipoprotein HDL subclasses were quantified by proton nuclear magnetic resonance spectroscopy. At follow-up, the baseline data were analysed for incident micro- or macroalbuminuria (117 cases in 5.3 years), progression from microalbuminuria (63 cases in 6.1 years), progression from macroalbuminuria (109 cases in 5.9 years) and mortality (385 deaths in 9.4 years). Univariate associations were tested by age-matched cases and controls and multivariate lipoprotein profiles were analysed using the self-organizing map (SOM). RESULTS: TG and C levels in large VLDL were associated with incident albuminuria, TG and C in medium VLDL were associated with progression from microalbuminuria, and TG and C in all VLDL subclasses were associated with mortality. Large HDL-C was inversely associated with mortality. Three extreme phenotypes emerged from SOM analysis: (i) low C (<3% mortality), (ii) low TG/C ratio (6% mortality), and (iii) high TG/C ratio (40% mortality) in all subclasses. CONCLUSIONS: TG-C imbalance is a general lipoprotein characteristic in individuals with T1DM and high vascular disease risk.

Lipoprotein receptor-related protein 1 variants and dietary fatty acids: meta-analysis of European origin and African American studies.

OBJECTIVE: Low-density lipoprotein-related receptor protein 1 (LRP1) is a multi-functional endocytic receptor and signaling molecule that is expressed in adipose and the hypothalamus. Evidence for a role of LRP1 in adiposity is accumulating from animal and in vitro models, but data from human studies are limited. The study objectives were to evaluate (i) relationships between LRP1 genotype and anthropometric traits, and (ii) whether these relationships were modified by dietary fatty acids. DESIGN AND METHODS: We conducted race/ethnic-specific meta-analyses using data from 14 studies of US and European whites and 4 of African Americans to evaluate associations of dietary fatty acids and LRP1 genotypes with body mass index (BMI), waist circumference and hip circumference, as well as interactions between dietary fatty acids and LRP1 genotypes. Seven single-nucleotide polymorphisms (SNPs) of LRP1 were evaluated in whites (N up to 42 000) and twelve SNPs in African Americans (N up to 5800). RESULTS: After adjustment for age, sex and population substructure if relevant, for each one unit greater intake of percentage of energy from saturated fat (SFA), BMI was 0.104 kg m(-2) greater, waist was 0.305 cm larger and hip was 0.168 cm larger (all P<0.0001). Other fatty acids were not associated with outcomes. The association of SFA with outcomes varied by genotype at rs2306692 (genotyped in four studies of whites), where the magnitude of the association of SFA intake with each outcome was greater per additional copy of the T allele: 0.107 kg m(-2) greater for BMI (interaction P=0.0001), 0.267 cm for waist (interaction P=0.001) and 0.21 cm for hip (interaction P=0.001). No other significant interactions were observed. CONCLUSION: Dietary SFA and LRP1 genotype may interactively influence anthropometric traits. Further exploration of this, and other diet x genotype interactions, may improve understanding of interindividual variability in the relationships of dietary factors with anthropometric traits.

Temperament, character and serotonin activity in the human brain: a positron emission tomography study based on a general population cohort.

BACKGROUND: The psychobiological model of personality by Cloninger and colleagues originally hypothesized that interindividual variability in the temperament dimension 'harm avoidance' (HA) is explained by differences in the activity of the brain serotonin system. We assessed brain serotonin transporter (5-HTT) density in vivo with positron emission tomography (PET) in healthy individuals with high or low HA scores using an 'oversampling' study design. Method Subjects consistently in either upper or lower quartiles for the HA trait were selected from a population-based cohort in Finland (n = 2075) with pre-existing Temperament and Character Inventory (TCI) scores. A total of 22 subjects free of psychiatric and somatic disorders were included in the matched high- and low-HA groups. The main outcome measure was regional 5-HTT binding potential (BPND) in high- and low-HA groups estimated with PET and [11C]N,N-dimethyl-2-(2-amino-4-methylphenylthio)benzylamine ([11C]MADAM). In secondary analyses, 5-HTT BPND was correlated with other TCI dimensions. RESULTS: 5-HTT BPND did not differ between high- and low-HA groups in the midbrain or any other brain region. This result remained the same even after adjusting for other relevant TCI dimensions. Higher 5-HTT BPND in the raphe nucleus predicted higher scores in 'self-directedness'. CONCLUSIONS: This study does not support an association between the temperament dimension HA and serotonin transporter density in healthy subjects. However, we found a link between high serotonin transporter density and high 'self-directedness' (ability to adapt and control one's behaviour to fit situations in accord with chosen goals and values). We suggest that biological factors are more important in explaining variability in character than previously thought.

Neuropeptide Y polymorphism increases the risk for asthma in overweight subjects; protection from atherosclerosis in asthmatic subjects--the cardiovascular risk in young Finns study.

AIMS: The role of neuropeptide Y (NPY) and its gene polymorphisms in the development of atherosclerosis has become increasingly evident. In asthma, NPY has been shown to be involved as immunomodulator. In this study, we investigated the role of two functional NPY polymorphisms, NPY-Leu7Pro (rs16139) and NPY-399C/T (rs16147) and obesity for the development of asthma as well as atherosclerosis in asthmatic and non-asthmatic subjects. Also, we measured heart rate variability (HRV) and NPY in serum since these might contribute through these polymorphisms to both diseases. METHODS AND RESULTS: Thousand hundred and seventy six Finnish young adults were genotyped and three groups (G1-G3) were formed based on the observed diplotypes. The NPY-Pro7 allele always co-existed with the NPY-399T allele indicating complete linkage disequilibrium. Here we show that overweight (BMI≥25kg/m2) was associated with 2.5-fold increased risk for asthma in subjects with the NPY-399T allele without NPY-Pro7 allele (G2, n=716). Overweight was also associated with increased atherosclerosis determined by carotid intima media thickness (cIMT), but asthma seemed to be more significant determinant than overweight in determing cIMT having a decreasing effect. NPY concentration in serum was diplotype-driven (G1=792.2(29.5), G2=849.0(18.9), G3=873.9(45.2) pg/ml) and correlated positively with cIMT in the group having NPY-Pro7 allele (G3, n=142). However, the subjects with asthma had a negative NPY-cIMT relationship. Total HRV was increased in asthma and correlated negatively with cIMT irrespective of the NPY genotype. CONCLUSIONS: Overweight together with the NPY-399T allele without NPY-Pro7 allele was associated with increased risk for asthma. Atherosclerosis was decreased in subjects with asthma depending on the NPY genotype. The results reveal novel insights into the genetics and biology of the relationship of atherosclerosis and asthma.

Body mass index and depressive symptoms: instrumental-variables regression with genetic risk score.

The causal role of obesity in the development of depression remains uncertain. We applied instrumental-variables regression (Mendelian randomization) to examine the association of adolescent and adult body mass index (BMI) with adult depressive symptoms. Participants were from the Young Finns prospective cohort study (n = 1731 persons, 2844 person-observations), with repeated measurements of BMI and depressive symptoms (modified Beck's Depression Inventory). Genetic risk score of 31 single nucleotide polymorphisms previously identified as robust genetic markers of body weight was used as a proxy for variation in BMI. In standard linear regression analysis, higher adult depressive symptoms were predicted by higher adolescent BMI (B = 0.33, CI = 0.06-0.60, P = 0.017) and adult BMI (B = 0.47, CI = 0.32-0.63, P < 0.001). These associations were replicated in instrumental-variables analysis with genetic risk score as instrument (B = 1.96, CI = 0.03-3.90, P = 0.047 for adolescent BMI; B = 1.08, CI = 0.11-2.04, P = 0.030 for adult BMI). The association for adolescent BMI was significantly stronger in the instrumented analysis compared to standard regression (P = 0.04). These findings provide additional evidence to support a causal role for high BMI in increasing symptoms of depression. However, the present analysis also demonstrates potential limitations of applying Mendelian randomization when using complex phenotypes.

A genome-wide meta-analysis of association studies of Cloninger's Temperament Scales.

Temperament has a strongly heritable component, yet multiple independent genome-wide studies have failed to identify significant genetic associations. We have assembled the largest sample to date of persons with genome-wide genotype data, who have been assessed with Cloninger's Temperament and Character Inventory. Sum scores for novelty seeking, harm avoidance, reward dependence and persistence have been measured in over 11,000 persons collected in four different cohorts. Our study had >80% power to identify genome-wide significant loci (P<1.25 × 10(-8), with correction for testing four scales) accounting for ≥0.4% of the phenotypic variance in temperament scales. Using meta-analysis techniques, gene-based tests and pathway analysis we have tested over 1.2 million single-nucleotide polymorphisms (SNPs) for association to each of the four temperament dimensions. We did not discover any SNPs, genes, or pathways to be significantly related to the four temperament dimensions, after correcting for multiple testing. Less than 1% of the variability in any temperament dimension appears to be accounted for by a risk score derived from the SNPs showing strongest association to the temperament dimensions. Elucidation of genetic loci significantly influencing temperament and personality will require potentially very large samples, and/or a more refined phenotype. Item response theory methodology may be a way to incorporate data from cohorts assessed with multiple personality instruments, and might be a method by which a large sample of a more refined phenotype could be acquired.

Relation of high cytomegalovirus antibody titres to blood pressure and brachial artery flow-mediated dilation in young men: the Cardiovascular Risk in Young Finns Study.

Human cytomegalovirus (CMV) infection is associated with a higher risk of cardiovascular disease in immunocompromised organ transplant patients. It has been linked with the pathogenesis of elevated arterial blood pressure. However, controversy exists as to whether CMV infection is associated with endothelial function, and little is known about its role as a potential risk factor for early atherosclerosis development at a young age. We aimed to discover if CMV antibody titres are associated with early vascular changes (carotid intima-media thickness, carotid artery distensibility and brachial artery flow-mediated dilation), blood pressure elevation or other traditional cardiovascular risk factors. CMV antibody titres were measured in 1074 women and 857 men (aged 24-39 years) taking part in the Cardiovascular Risk in Young Finns study. CMV antibody titres were significantly higher in women compared to men. In men, high CMV antibody titres were associated directly with age (P < 0·001) and systolic (P = 0·053) and diastolic (P = 0·002) blood pressure elevation, and associated inversely with flow-mediated dilation (P = 0·014). In women, CMV antibody titres did not associate with any of the analysed parameters. In a multivariate regression model, which included traditional atherosclerotic risk factors, CMV antibody titres were independent determinants for systolic (P = 0·029) and diastolic (P = 0·004) blood pressure elevation and flow-mediated dilation (P = 0·014) in men. High CMV antibody titres are associated independently with blood pressure and brachial artery flow-mediated dilation in young men. This association supports the hypothesis that common CMV infection and/or an immune response to CMV may lead to impaired vascular function at a young age.