Primary objective: We tested whether fasting insulin levels are associated with blood pressure in a large sample of obese children.
Subjects and methods: Three hundred and fifty obese children (F:M ratio = 1.03) of 10.1 +/- 2.7 y of age (mean +/- SD) were consecutively enrolled at an Outpatient Paediatric Clinic. Obesity was diagnosed on the basis of a relative weight for age > 120% and hypertension on the basis of a systolic (SBP) or diastolic (DBP) blood pressure > 95th percentile for age after adjustment for height (Ht).
Main outcome and results: Insulin was significantly higher in hypertensive (n = 202, 58%) than normotensive (n = 148, 42%) children (16 vs 14 microU mL(-1), geometric mean, p < 0.01, ANOVA) but the difference was not clinically relevant. Moreover, (log-transformed) insulin explained only 7 and 4% of SBP and DBP variance, respectively (p < 0.0001 for both) and this contribution disappeared after the confounding effects of age, weight or other anthropometric dimensions were taken into account (p = ns, ANCOVA).
Conclusions: This study does not support the hypothesis of a clinically relevant association between fasting insulin and blood pressure in obese children.