Incidence of type-2 diabetes among industrial Workers in Kerala, India

Kerala is the most advanced Indian state in epidemiological transition and has the highest type 2 diabetes prevalence. However, data on incidence of diabetes in Kerala are limited. We studied the incidence of diabetes and pre-diabetes among industrial workers. We measured fasting plasma glucose (FPG) among 326 workers (mean age 51 years, men 76 %) from two major industries in Kerala in the years 2009 and 2011 using standard protocol. Individuals with FPG >= 126 mg/dl or on medications for diabetes were considered to have diabetes mellitus, FPG >= 100 mg/dl and <= 125/dl mg as pre-diabetic, and FPG <100 mg/dl as normal. Among the 326 workers, 26.1 % (95 % CI 21.6-31.1) were diabetic, 32.8 % (CI 28.7-37.2) were pre-diabetic, and the remaining 41.1 % were having normal FPG at baseline. At year two, 13.3 % of the 241 workers who were either normal or had pre-diabetes at baseline developed diabetes providing an incidence rate of 6.65 % per year. Among the 134 workers with normal FPG at baseline 28.4 % progressed to pre-diabetes, 5.2 % developed diabetes, and among the 107 pre-diabetics, 23.4 % developed diabetes at year two. The odds of progressing to diabetes from pre-diabetes were five times higher compared to those from normal FPG (OR 5.53; CI 2.28-13.37). Progression to pre-diabetes and diabetes occurred at a very fast rate in this population indicating the need for preventive measures to slow down this fast progression.