The relationship between resting blood pressure, body mass index and lean body mass index in British children

BACKGROUND: Elevated blood pressure (BP) in childhood is associated with overweight and obesity. However, lean body mass index (LBMI, cm(2)/kg) has been suggested as a better means than body mass index (BMI, kg/m(2)) by which to consider the relations between weight status and health indices in children. OBJECTIVE: To assess the relationship between resting BP and weight status in youth whilst considering BMI and LBMI when examining this issue. METHODS AND PROCEDURES: Height, body mass and resting blood pressure were assessed in 384 boys and 277 girls, aged 11-14 years from Central England. RESULTS: SBP was significantly lower in 'normal weight' children compared to overweight and obese children and in overweight compared to obese children (both p = 0.0001). DBP was significantly lower in 'normal weight' children compared to those classified as overweight (p = 0.006). BMI and LBMI were both significant predictors of SBP and DBP (p = 0.0001). However, LBMI was normally distributed, unlike BMI, and was a better predictor of BP than BMI. CONCLUSIONS: Overweight and obesity is associated with higher resting BP in British children. However, when examining the effect of weight status on BP, the researcher should consider use of LBMI over BMI.