Association between insulin, leptin, adiponectin and blood pressure in youth

To examine whether insulin, leptin and adiponectin are independent correlates of blood pressure (BP) in a large population-based sample of children and adolescents.

We studied 655 boys and 667 girls aged 9, 13 and 16 years who participated in the Quebec Child and Adolescent Health and Social Survey, a province-wide school-based survey conducted in 1999.

Strong, positive univariate associations between BMI, insulin and leptin Z-scores, and both systolic and diastolic BP were found in both sexes. Adiponectin Z-scores were negatively associated with systolic BP in girls only. In multivariate analyses only BMI and insulin Z-scores were significantly associated with systolic BP. In boys, each 1 SD increase in BMI was associated with a 4 mmHg increase in mean systolic BP; each 1 SD increase in insulin was associated with a 1 mmHg increase in mean systolic BP. Only insulin Z-scores were independently associated with diastolic BP in both sexes. For each 1 SD increase in insulin, there was a 1 mmHg increase in mean diastolic BP in boys. Similar to systolic BP, the magnitude of the effect of insulin Z-scores on diastolic BP increased as a function of BMI Z-scores in girls.

Independently of BMI, insulin is a strong correlate of systolic and diastolic BP in youth. Although animal studies support a role for leptin and adiponectin in controlling BP, they are not independently associated with BP in youth.