Comparison of body mass index and triceps skinfold at 5 years and young adult body mass index, waist circumference and blood pressure

Aim: To examine which measure of obesity at 5 years, body mass index (BMI) or triceps skinfold thickness, is most strongly associated with 21-year risk factors for cardiovascular disease (CVD), including BMI, waist circumference (WC), systolic blood pressure (SBP) and diastolic blood pressure (DBP). Methods: Longitudinal birth cohort study with BMI and triceps skinfold measurements at age 5, and BMI, WC and blood pressure at 21 years. Overweight and obesity at 5 years were determined according to Cole-International Obesity Task Force standards, at 21, by World Health Organization definitions. Triceps skinfold thickness measurements were converted to a z-score, and cut-offs for overweight and obesity were chosen to reflect similar proportions to the BMI subgroups. BMI, WC, SBP and DBP were also measured at 21 years. Results: Five-year BMI and triceps skinfold thickness were both significantly associated with the CVD risk measures at 21 years. For overweight/obesity at 5 years, the adjusted odds ratio (95% confidence interval) for 21-year overweight/obesity was 5.6 (4.2, 7.4), for 21-year WC was 1.5 (1.2, 2.0). Mean difference (95% CI) in BMI was 4.4 (3.9, 5.0), in WC 8.3 cm (6.8, 9.8), in SBP 2.4 mm Hg (0.5, 4.3), in DBP 1.1 mm Hg (0.1, 2.2). For skinfold, the similar findings were odds ratio 2.6 (2.0, 3.4) and 1.2 (0.9, 1.6) for 21-year BMI and WC, and mean differences of 2.6 (2.0, 3.2), WC 4.8 cm (3.3, 6.3), SBP 2.3 mm Hg (0.5, 4.2) and DBP 0.7 mm Hg (-0.4, 1.8). Conclusions: In children with overweight/obesity, BMI rather than triceps skinfold is the preferred epidemiological measure for identifying young adult CVD risk markers of BMI, WC and blood pressure