Prevalence of obesity and its associations among adolescents: an urban community-based birth cohort study

Abstract

INTRODUCTION & OBJECTIVES: Community based data on childhood obesity is lacking. We investigated the community prevalence and associations for adolescent obesity. METHODS: Fourteen-year-olds (Year-2000 birth-cohort), from Ragama MOH area were included. Demographic and life style data was collected. Standard blood biochemistry was performed. Physical activity (PA) and sedentary time (ST) were assessed using the short version of the International Physical Activity Questionnaire (IPAQ). Body mass index (BMI), waist circumference (WC) and blood pressure were measured. Total body fat (TBF%) was measured using impedance method. Multiple logistic regression was used to assess relationships between demography, life style habits, anthropometry, TBF% and biochemistry with obesity. RESULTS: A total of 508 [261 (51.6%)-girls, median birth weight-2.9 (IQR: 2.6-3.2) kg, 9 (1.78%) had maternal gestational diabetes (GDM), with median age of menarche-12 [IQR: 11-13] years] participated in the study. 61 (12.0%) had general obesity (GO) (BMI>age-sex equivalent of 23kg/m2) [33 (11.4%)-girls, 28 (12.7%)-boys; p=0.76]. 136 (27.0%) had central obesity (CO) (WC>cut-off for age and sex) [97 (37.3%)-girls, 39 (16.0%)-boys; p<0.01]. Median TBF% was 19.4 (IQR: 14.2-23.5). 10 (2.0%) had abnormal TBF% [3 (1.1%)-girls, 7 (2.9%)-boys; p=0.21]. Those engaging in some-PA [below recommendation (duration<150 min/week) and recommended-PA [at or above recommendation (duration≥150 min/week)] among girls were 129 (49.4%) and 132 (50.6%) while among boys were 116 (48.1%) and 125 (51.9%) respectively. Those with ST≥4 hour, <4 hours for girls and boys were 63 (24.4%), 195 (75.6%) and 31 (12.7%), 213 (87.3%) respectively. HOMA-IR median was 120.3 (IQR: 86.2-173.8). On multiple logistic regression, birth weight (OR-1.01; p<0.01), age at menarche (OR-1.48; p<0.05), TBF% (OR-2.27; p<0.001) and HOMA-IR (OR-1.01; p<0.001) were significantly associated with CO while PA or ST were not. CONCLUSION: Central obesity among adolescent girls was significantly more than boys. Adolescent central obesity was associated with birth weight, age at menarche, adverse TBF% and insulin resistance.