Prevalence of dementia in Chinese elderly in Hong Kong.

This study examines the prevalence of dementia in elderly Chinese aged 70 years and older in Hong Kong using a two-phase design. In phase 1, 1,034 elderly were interviewed with the Cantonese version of the Mini-Mental State Examination. Those who scored below the cutoff points and a subsample of those with scores in the normal range were interviewed in phase 2 to identify those with dementia. The overall weighted prevalence of dementia in our subjects was 6.1 +/- 0.7%, which is at the lower end of the range of rates reported in whites. Alzheimer's disease (AD) accounted for 64.6% and vascular dementia, 29.3%. Our results, together with previous studies in Chinese populations, suggest that the rates of AD in Chinese are low compared with those in whites. Substantial differences are possible in the epidemiology of dementia across cultures related to interactions of genetic and environmental factors.