Cross-sectional associations between physical activity and selected coronary heart disease risk factors in young adults. The Cardiovascular Risk in Young Finns Study

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.

Ideal cardiovascular health in adolescence: effect of lifestyle intervention and association with vascular intima-media thickness and elasticity (the Special Turku Coronary Risk Factor Intervention Project for Children [STRIP] study)

BACKGROUND

In the Special Turku Coronary Risk Factor Intervention Project for Children (STRIP) study, repeated dietary counseling introduced in infancy and maintained until 20 years of age has led to lower intakes of saturated fat and serum low-density lipoprotein cholesterol. In this study, we examined prospectively the intervention effects on the ideal cardiovascular health concept recently described by the American Heart Association. Additionally, we investigated the association between the concept and vascular intima-media thickness and elasticity in adolescence.

METHODS AND RESULTS

In adolescents participating in the longitudinal, randomized, atherosclerosis-prevention STRIP study, complete data on ideal cardiovascular health metrics were available at 15 (n=394), 17 (n=376), and 19 (n=298) years of age. Aortic intima-media thickness and elasticity were measured with ultrasonography at the same ages. None of the adolescents had all 7 ideal cardiovascular health metrics. At least 5 ideal metrics was found in 60.2%, 45.5%, and 34.2% of the adolescents at 15, 17, and 19 years of age, respectively. Adolescents in the control group had an increased risk of low ideal cardiovascular health (≤3 metrics) compared with the intervention adolescents (risk ratio=1.35; 95% confidence interval=1.04-1.77). The number of ideal cardiovascular health metrics was inversely associated with aortic intima-media thickness (P<0.0001) and directly associated with elasticity (P=0.045). The risk of having high intima-media thickness (>85th percentile) was nearly 2-fold in adolescents with a low number of metrics (≤3) compared with those with a higher score (risk ratio=1.78; 95% confidence interval=1.31-2.43).

CONCLUSIONS

Ideal cardiovascular health as determined by the AHA can be promoted in adolescents. The ideal cardiovascular health concept is beneficially associated with vascular health already in adolescence, supporting the relevance of targeting these metrics as part of primordial prevention.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00223600.

Childhood nutrition in predicting metabolic syndrome in adults: the cardiovascular risk in Young Finns Study

OBJECTIVE

Our aim was to study the associations of childhood lifestyle factors (the frequency of consumption of vegetables, fruit, fish, and meat, butter use on bread, and physical activity) with the metabolic syndrome (MetS) in adulthood.

RESEARCH DESIGN AND METHODS

The study cohort consisted of 2,128 individuals, 3-18 years of age at the baseline, with a follow-up time of 27 years. We used the average of lifestyle factor measurements taken in 1980, 1983, and 1986 in the analyses. Childhood dietary factors and physical activity were assessed by self-reported questionnaires, and a harmonized definition of MetS was used as the adult outcome.

RESULTS

Childhood vegetable consumption frequency was inversely associated with adult MetS (odds ratio [OR] 0.86 [95% CI 0.77-0.97], P = 0.02) in a multivariable analysis adjusted with age, sex, childhood metabolic risk factors (lipids, systolic blood pressure, insulin, BMI, and C-reactive protein), family history of type 2 diabetes and hypertension, and socioeconomic status. The association remained even after adjustment for adulthood vegetable consumption. Associations with the other childhood lifestyle factors were not found. Of the individual components of MetS, decreased frequency of childhood vegetable consumption predicted high blood pressure (0.88 [0.80-0.98], P = 0.01) and a high triglyceride value (0.88 [0.79-0.99], P = 0.03) after adjustment for the above-mentioned risk factors.

CONCLUSIONS

Childhood vegetable consumption frequency is inversely associated with MetS in adulthood. Our findings suggest that a higher intake of vegetables in childhood may have a protective effect on MetS in adulthood.

Metabolic signatures of insulin resistance in 7,098 young adults

Metabolite associations with insulin resistance were studied in 7,098 young Finns (age 31 ± 3 years; 52% women) to elucidate underlying metabolic pathways. Insulin resistance was assessed by the homeostasis model (HOMA-IR) and circulating metabolites quantified by high-throughput nuclear magnetic resonance spectroscopy in two population-based cohorts. Associations were analyzed using regression models adjusted for age, waist, and standard lipids. Branched-chain and aromatic amino acids, gluconeogenesis intermediates, ketone bodies, and fatty acid composition and saturation were associated with HOMA-IR (P < 0.0005 for 20 metabolite measures). Leu, Ile, Val, and Tyr displayed sex- and obesity-dependent interactions, with associations being significant for women only if they were abdominally obese. Origins of fasting metabolite levels were studied with dietary and physical activity data. Here, protein energy intake was associated with Val, Phe, Tyr, and Gln but not insulin resistance index. We further tested if 12 genetic variants regulating the metabolites also contributed to insulin resistance. The genetic determinants of metabolite levels were not associated with HOMA-IR, with the exception of a variant in GCKR associated with 12 metabolites, including amino acids (P < 0.0005). Nonetheless, metabolic signatures extending beyond obesity and lipid abnormalities reflected the degree of insulin resistance evidenced in young, normoglycemic adults with sex-specific fingerprints.