Rarity of dementia (by DSM-III-R) in an urban community in Nigeria.

Dementia of the elderly, a public health problem world-wide, is underdocumented in black Africa. We carried out a door-to-door survey in Idikan in NW3 ward, a political and administrative unit, with a population of 9000: in Ibadan city, Nigeria, to determine the burden of dementia. Census and demographic listing was done by trained clinical students who concurrently administered a modified Mini Mental State Examination as a screening instrument to those aged 40 years or more. Only 2 out of 932 subjects refused: 293 (31%) were aged 65 years or more. Those who were positive to the screening test and 20% of negatives were investigated by neurologists. Decline in cognitive function significantly correlated with age, female sex and low level of education. Impaired cognition was present in 41 (4.4%) but was due to depressive disorders in 7 (0.6%) patients. In none of the remaining 34 (3.8%) subjects could a diagnosis of dementia as defined by DSM-III-R be justified.