The association of cardiovascular risk factor clustering related to insulin resistance syndrome (Syndrome X) between young parents and their offspring: the Bogalusa Heart Study

Cardiovascular risk factor clustering related to insulin resistance syndrom e (Syndrome X) was examined in a community-based sample of 599 genetically unrelated school-aged children (5-17 years) and their parents. Risk factors used as components of Syndrome X included hyperinsulinemia, obesity, dysli pidemia and high blood pressure defined by values above the age-, sex- and race-specific 75th percentiles of fasting insulin, body mass index, triglyc erides/high-density lipoprotein cholesterol ratio and mean arterial pressur e, respectively. Based on observed to expected ratio there was an excess of parents (father and/or mother) and their offspring with clusters of three or four disorders (P < 0.05-0.001). In contrast, the number of parents and offspring with two disorders was significantly lower than expected by chanc e alone (P < 0.05-0.01). Based on paternal, maternal, and parental Syndrome X, the odds ratios (95% confidence interval) for offspring having the same cluster were 7.2 (1.9-27.2), 8.6 (3.1-23.6) and 7.9 (3.5-18.1), respective ly. In terms of individual risk factors of parents used as predictors, adve rse levels of their insulin and BMI significantly increased the risk of off spring having Syndrome X (P < 0.01-0.001), whereas the effect of parental i nsulin was considerably reduced after parental BMI was adjusted for. In con trast, parental dyslipidemia and high blood pressure were not associated wi th the occurrence of Syndrome X in their offspring. These results confirm t he familial nature of Syndrome X and suggest that conditions of obesity and the attendant hyperinsulinemia in parents may underlie this familial assoc iation. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.