Incidence and predictors of Diabetes Mellitus: A 7- year community cohort follow-up of urban, adult Sri Lankans

Abstract

INTRODUCTION & OBJECTIVES: There is limited data on incidence of type 2 diabetes mellitus (T2DM) from South Asia. We investigated incidence and predictors ofT2DM in an urban, adult population after seven-years of follow-up. METHODS: The study population (42-71 year-olds in 2014, selected by age-stratified random sampling from the Ragama MOH area) was initially screened in 2007 and re-evaluated in 2014 with informed written consent. On both occasions they were assessed by structured interview, anthropometric measurements, liver ultrasound, biochemical and serological tests. RESULTS: Of the 2986 enrolled in 2007, 737 had established T2DM giving a baseline prevalence of 24.7% (95% CI: 23.1%-26.2%). 2148/2984 (71.6%) of the original cohort attended follow-up [1237 (57.5%) women; median (IQR) 60 (54-66) years]. 1650 participants who did not have T2DM in 2007 presented for follow up; 436 (27.6%) of them had developed new T2DM by 2014, giving an annual incidence of 3.9% (95% CI: 3.0%-4.9%). Of 525 participants with pre-diabetes (HbA1c 5.7-6.4%) in 2007, 364 attended follow up and 201/364 (55.1%) had developed T2DM by 2014, giving an annual conversion rate of pre-diabetes to T2DM of 7.9%. On logistic regression, pre-diabetes (OR:4.4;95%CI:3.3%-6.0%), central obesity (OR: 1.8;95%CI: 1.3%-2.4%), dyslipidemia (OR: l.5;95%CI: 1.1 %-2.1 %) and non-alcoholic fatty liver disease (NAFLD) (OR:1.5;95%CI: 1.1 %-2.1%) showed significant association with incident T2DM. CONCLUSION: In this urban cohort, the annual incidence of T2DM was 3.9% and the annual conversion rate of pre-diabetes to T2DM was 7.9%. Our findings emphasize the need for targeted and intensive lifestyle interventions for individuals with high metabolic risk to prevent T2DM.