Physical activity modifies the associations between genetic variants and hypertension in the Chinese children

Childhood hypertension is a complex disease influenced by both genetic and environmental factors. We aimed to examine the effect of interactions of five polymorphisms with physical activity on blood pressure (BP)/hypertension in the Chinese children.

A population-based case-control study was carried out in Beijing of China in 2004, which included 619 hypertensive cases and 2458 normal BP controls. Physical activity information was collected through the use of a validated questionnaire, and five polymorphisms were genotyped using TaqMan. In active group, there was no significant association of five polymorphisms and genetic risk score with systolic/diastolic BP (SBP/DBP) and risk of hypertension (all p > 0.05). In contrast, in inactive group, two polymorphisms and genetic risk score were significantly associated with SBP (rs17249754: β = 1.26, 95% confidence interval (CI) 0.61-1.90, p < 0.001; rs1004467: β = 0.68, 95%CI 0.03-1.32, p = 0.039; genetic risk score: β = 1.54, 95%CI 0.74-2.33, p < 0.001); three polymorphisms and genetic risk score were significantly associated with hypertension (rs17249754: odds ratio (OR) = 1.27, 95%CI 1.08-1.49, p = 0.004; rs1378942: OR = 1.25, 95%CI 1.00-1.57, p = 0.050 (marginally significant); rs16998073: OR = 1.17, 95%CI 1.01-1.37, p = 0.044; genetic risk score: OR = 1.38, 95%CI 1.13-1.68, p = 0.001).

The present study provides evidence that interactions between recently identified variants and physical activity play important roles in the regulation of BP and development of hypertension. Physical activity should be prescribed for hypertensive children, especially for those with high risk genetic alleles.