Prevalence of dementia in an urban population in Kerala, India.

Abstract

Dementia is emerging as an important health problem of elderly people in India. To investigate the prevalence, psychosocial correlates and risk factors of various dementing disorders in an urban population in Kerala, southern India. A door-to-door survey was conducted in the city of Kochi (Cochin) to identify residents aged > or =65 years using cluster sampling. Of 1934 people screened with a vernacular adaptation of the Mini-Mental State Examination, all those scoring at or below the cut-off of 23 were evaluated further and those with confirmed cognitive and functional impairment were assigned diagnoses according to DSM-IV criteria. Identified cases were categorised by ICD-10 criteria. Ten per cent of those screened as negative were evaluated at each stage. Prevalence of dementia was 33.6 per 1000 (95% CI 27.3-40.7). Alzheimer's disease was the most common type (54%) followed by vascular dementia (39%), and 7% of cases were due to causes such as infection, tumour and trauma. Family history of dementia was a risk factor for Alzheimer's disease and history of hypertension was a risk factor for vascular dementia. Dementia is an important health problem of the elderly population. Identification of risk factors points towards the possibility of prevention.