Abstract 462: The Effect of Body Mass Index on Blood Pressure Varies by Race among Children Referred for Treatment of Obesity
Black school-aged children tend to have greater body mass index (BMI) and higher BP than their age-matched white peers. But few studies have considered racial differences in the magnitude of the effect of increasing BMI on BP among equally obese black and white children. We used a novel analytic technique to examine the influence of age and BMI on BP in children seen at a tertiary care center- based obesity clinic (POWER, Riley Hospital for Children, Indianapolis, IN). The study sample included 821 obese children (306 males, 515 females, 362 blacks, and 459 whites). The mean age of the study subjects was 11.72 ± 3.48 years, the mean BMI was 36.22 ± 8.51 kg/m2, and the mean systolic and diastolic BP were 109.36 ± 16.10 and 69.99 ± 10.48 mmHg, respectively. In comparison, blacks and whites were similar in age (11.89 vs 11.58; p=0.197); while black patients had higher mean BMI (37.32 vs 35.34 kg/m2; p=0.0010), and higher systolic BP% than whites (58.71 vs 50.72 mmHg; p=0.00062). Semiparametric regression models showed that while age and BMI were associated with systolic BP% in both race groups, black children had significantly higher BP% values as compared with white children of the same age and BMI (Fig 1). In conclusion, among children referred for treatment of obesity, there are race-dependent differences in the effect of BMI on blood pressure. Black children are at a significantly greater risk for having elevated BP as compared with their white peers of similar age and severity of obesity. Further research is needed to better understand this population-specific intensification of the adiposity effect on BP, as this has implications for clinical care and treatment of hypertension in black children.
- © 2012 by American Heart Association, Inc.