Epidemiology of goitres in Sri Lanka - results of a community based study

Abstract

BACKGROUND: lodization of salt was made mandatory in Sri Lanka in 1995. Data on the current prevalence and geographic distribution of goitre among the general population is not available. Objectives: To describe the epidemiology of goitre in the population over the age of 10 years in Sri Lanka DESIGN, SETTING AND METHODS: The country (excluding the Northern Province) was divided into 6 ecological zones based on annual rainfall and altitude. From each zone, 18 Grama Niladhari (GN) areas were selected, using the probability proportionate to size (PPS) technique. First household to be sampled was selected at random from the list maintained by the midwife and all eligible people in the house were sampled. The closest household, next to the index household,, was visited and sampling carried out next. The process was repeated until 50 subjects were sampled in a GN area. Each subject was examined by at least two researchers for the presence of a goitre. RESULTS: Total of 5200 subjects were assessed. 66 %( 3,433) were females. Mean (SD) age 36.3(17.3) years. 425 subjects had a goitre. The distribution of goitres according to the WHO categorization - Grades 1, 2, 3 and 4 was 18.6, 68.0, 12.5 and 0.9 percent respectively. Adjusted (age and zone) prevalence among females and males was 11.2% and 2.3% respectively. Adjusted (age and sex) prevalence (95% CI) in the different zones varied between 5.34% in the intermediate zone-south to 7.93% in the wet zone-hills. Overall adjusted prevalence was 6.8% (6.0-7.6). CONCLUSIONS: The prevalence of goitres is 6.8%. There is definite female preponderance. No obvious goitre belt can be discerned.