Tracking of cardiovascular risk factors across generations: family linkage within the population-based HUNT study, Norway.

BACKGROUND: Parent-offspring studies have shown that cardiovascular risk factors cluster within families. However, most studies have assessed the offspring cardiovascular risk factor level at a young age, and whether an association persists into the offspring's adult life is less clear. This study linked information between parents and their adult offspring to investigate the intergenerational association of anthropometric measures, blood pressure, blood lipid levels and physical activity.
METHODS: The study population consisted of parent and adult offspring pairs (11,931 fathers-sons, 12,563 fathers-daughters, 15,626 mothers-sons and 16,449 mothers-daughters) who participated in the second and third cross-sectional waves of the Nord-Trøndelag Health Study (HUNT 2, 1995-1997 and HUNT 3, 2006-2008). A general linear model and logistic regression were used to estimate the association between the parent and offspring risk factor levels.
RESULTS: All continuously measured cardiovascular risk factors under study showed a statistically significant positive association between parents and offspring, except the waist-hip ratio. Adjusted coefficients from linear regression ranged from 0.09 (95% CI 0.07 to 0.11) for waist circumference to 0.29 (95% CI 0.27 to 0.32) for body weight. Moreover, offspring were two to three times more likely to be obese, have a high cholesterol level, or hypertension when comparing extreme categories of the corresponding parental risk factor level. Physically active parents had a lower risk of having physically inactive offspring.
CONCLUSIONS: The results suggested that cardiovascular risk factors track across generations and persist into the offspring's adult life.