Prevalence of sleep abnormalities and their association among hypothyroid patients in an Indian population.

Objective: To estimate the prevalence of sleep abnormalities and their association with hypothyroidism and metabolic risk factors in a relatively lean urban South Indian population.

Methods: This population-based, cross-sectional study was carried out in the urban population of Chennai, one of the largest metropolitan cities of India. Phase 1 was conducted in the field and involved a door-to-door survey of 26,000 individuals.