Social, cultural and economical determinants of diabetes mellitus in Kalutara district, Sri Lanka: a cross sectional descriptive study

INTRODUCTION: Sri Lanka is a country that is expected to face a high burden of diabetes mellitus (DM). There is a paucity of data on social and demographic determinants of DM, especially in the plantation sector. AIMS: To describe social and economic correlates and inequalities of DM in Kalutara District. METHODS: A cross sectional descriptive study was carried out among adults over the age of 35 years. A sample of 1300 individuals was selected using stratified random cluster sampling method from 65 Grama Niladari Divisions (GND), which were representative of urban, rural and plantation sectors. Twenty households were randomly selected from each division and one adult was randomly selected from each household. Data were collected using a pre-tested questionnaire. Fasting plasma blood sugar of ≥126mg/dl was used to define DM. Significance of prevalence of diseases and risk factors across different socio-economic strata were determined by chi square test for trend. RESULTS: Of 1234 adults who were screened (628 males), 202 (14.7%) had DM. Higher DM proportions (16.1%) were seen in the highest income quintile and in those educated up to Advanced Levels (AL) and above (17.3%). Prevalence in the urban, rural and plantation sectors were 23.6%, 15.5% and 8.5% respectively. Prevalence among Sinhalese, Tamils and Muslims were 14.4%, 29.0% and 20.0% respectively. There was a gradient in prevalence according to the unsatisfactory basic needs index of the GND with the highest proportion (20.7%) observed in the richest GND. The highest social status quintile demonstrated the highest proportion (17.4%) with diabetes mellitus. CONCLUSION: There is a higher prevalence of diabetes mellitus in the more affluent and educated segments of society. There is also a higher prevalence among urban compared to rural and estates. Sri Lanka is in an early stage of the epidemic where the wealthy people are at a higher risk of DM.