Longitudinal relationship between skinfolds ratios and blood pressure from childhood to late adolescence among Ellisras rural children: Ellisras Longitudinal Study

Abstract

This study aimed to investigate the longitudinal relationship between central body fat pattern, otherwise known as centripetal fat  patterning, with blood pressure (BP) from childhood into adolescence among Ellisras rural children. Anthropometric measurements and  BP were taken twice a year from 1999 to 2003 according to the standard procedures. In total, 1961 (1029 boys and 932 girls) Ellisras rural  children of mean age 9.2 years were followed throughout the five-year period. In 2003, 1716 children (876 boys and 840 girls) of mean  age 13.9 years were still in the study. The proportion of body fat on the trunk relative to that on the limbs was used as an indicator of fat  patterning (visceral fat). A longitudinal tracking (Generalized Estimating Equation (GEE) technique, which measures the association  between an indicator at the first period of measurements and the same indicator at all other periods of measurements, was used with  gender and age being included in the model. The skinfold ratio (subscapular + suprailiac / (subscapular + suprailiac + biceps + triceps)  was significantly (p<0.05) associated with systolic blood pressure (SBP) before adjusting for age, gender and 1600m run (beta= 9.9;  95%CI= 3.9–15.8). Waist circumference was significantly associated with SBP (beta=0.5; 95%CI= 0.4–0.6) after adjusted for age, gender and  1600m run (beta= 0.63; 95%CI= 0.2–1.0). While diastolic BP (DBP) (beta =0.2; 95%CI= 0.2–0.3) showed positive significant association  with waist girth even after adjusting for age, gender and 1600m run (beta= 0.3; 95%CI= 0.1–0.6). The increase in a central body fat pattern  was associated with increased BP in early life amongst Ellisras rural children.