Incidence and predictors of metabolic syndrome among urban, adult Sri Lankans: a community cohort, 7-year follow-up study

Abstract

BACKGROUND AND AIMS In 2007, we reported a 38.9% prevalence of metabolic syndrome (MetS) in an urban, adult population. Published data on incident MetS from South Asia is lacking. This study investigated the incidence and risk factors for MetS after a 7-year follow-up of the initial cohort. MATERIALS AND METHODS: The study population (selected by age-stratified random sampling from the Ragama MOH area) was screened in 2007 (aged 35-64 years) and re-evaluated in 2014 (aged 42-71 years). On both occasions, structured interview, anthropometric measurements, liver ultrasound, biochemical and serological tests were performed. MetS was diagnosed on established International Diabetes Federation (IDF 2012) criteria. Total body fat (TBF) and visceral fat percentage (VFP) were measured in 2014, using impedance. Abnormal TBF was defined as >32% for females and >25% for males. Abnormal VFP was defined as >10% for both sexes. Non-alcoholic fatty liver disease (NAFLD) was diagnosed on established ultrasound criteria, safe alcohol consumption (Asian standards: <14 units/week for men, <7 units/week for women) and absence of hepatitis B and C markers. RESULTS: 2137/2967 (72.0%) of the initial cohort attended follow-up [1229 (57.5%) women; mean-age 52.4 (SD-7.7) years]. 1000/2137 [548 (54.8%) women; mean age 57.5 years (SD-7.74)] had MetS (prevalence-46.8%). Out of 1246 individuals who initially did not have MetS in 2007, 318 [225 (70.8%) women; mean age 57.5 (SD 7.7) years] had developed incident MetS after 7 years (annual incidence-2.13%). Comparison of incident MetS with those with no MetS in 2014 is shown in Table 1. On logistic regression, female sex (OR 3.6, p<0.001), central obesity [OR 4.58, p<0.001], BMI >23kg/m2 [OR 4.84, p<0.001], increase in weight 2%-5% [OR 2.02, p<0.001], increase in weight >5% [OR 5.3, p<0.001), increase in waist circumference (WC) 5-10-cm [OR 3.68, p<0.001], increase in WC >10cm [OR 10.34, p<0.001] and NAFLD (OR 2.44, p<0.001) in 2007 were independently predictive of incident MetS in 2014. Abnormal VFP [OR 4.23, p<0.001] and abnormal TBF [OR 5.25, p<0.001] were also associated with incident MetS. CONCLUSION: In this prospective community study, the annual incidence of MetS was 2.13%. Female gender, increase in weight and WC from baseline and the presence of NAFLD predicted the development of incident MetS. Obesity at baseline was the only defining individual component of MetS that predicted future MetS.