Incidence, prevalence and demographic and life style risk factors for obesity among urban, adult Sri Lankans: a community cohort follow-up study

Abstract

INTRODUCTION & OBJECTIVES: Obesity is a global problem. Data from the South Asian region is limited. METHODS: In a cohort follow-up study we investigated obesity among urban, adult, Sri Lankans (35-64y; selected by age-stratified random sampling from Ragama-MOH area; initial screening 2007; re-evaluation 2014). On both occasions structured interview, anthropometry, liver ultrasound, biochemical and serological tests were performed. Total body fat (TBF) and visceral fat percentage (VFP) were assessed by impedance in 2014. General-obesity (GO) was BMI>25kg/m2. Central-obesity (CO) was waist circumference (WC)>90cm males and WC>80cm females. Multinomial logistic regression was fitted to assess associations. RESULTS: In 2007 (n=2967), 614 (20.7%) were overweight [51.9%-women], 1161(39.1%) had GO [65.9%-women] and 1584(53.4%) had CO [71%-women]. Females (p<0.001), raised-TG (p<0.001), low-HDL (p<0.001), diabetes (p<0.001), hypertension (p<0.001), NAFLD (p<0.001), and low household income (p<0.001) were significantly associated with prevalent GO and CO respectively. Additionally, increased-age (p=0.05), low-educational level (p<0.001) and unhealthy eating (p<0.001) were associated with prevalent CO. Inadequate physical activity was not associated with either. 2137 (72%) attended follow-up in 2014. Of those who were initially non-obese who attended follow-up, 189/1270 (14.9%) [64% women] had developed GO (annual-incidence 2.13%) and 206/947 (21.9%) [56.3% women] had developed CO (annual incidence 3.12%) after 7 years. TBF and VFP significantly correlated with incident GO and CO (p<0.001). Female gender (OR-1.78, p<0.001; 2.81, p<0.001) and NAFLD (OR-2.93, p<0.001; OR-2.27, p<0.001) independently predicted incident GO and CO respectively. CONCLUSION: The prevalence and incidence of GO and CO were high in this cohort. Both incident GO and CO were strongly associated with female gender and NAFLD.