Self-reported visual impairment and impact on vision-related activities in an elderly Nigerian population: report from the Ibadan study of ageing.

BACKGROUND: Studies have shown an association between visual impairment and poor overall function. Studies from Africa and developing countries show high prevalence of visual impairment. More information is needed on the community prevalence and impact of visual impairment among elderly Africans.
METHODS: A multi-stage stratified sampling of households was implemented to select persons aged 65 years and over in the south-western and north-central parts of Nigeria. Impairments of distant and near vision were based on subjective self-reports obtained with the use of items derived from the World Health Organization multi-country World Health Survey questionnaire. Impairment was defined as reporting much difficulty to questions on distant and near vision. Disabilities in activities of daily living (ADL) and instrumental activities of daily living (IADL) were evaluated by interview, using standardized scales.
RESULTS: A total of 2054 subjects 957 (46.6%) males and 1097 (53.4) females responded to the questions on vision. 22% (n = 453) of the respondents reported distant vision impairment, and 18% (n = 377) reported near vision impairment (not mutually exclusive). Fifteen percent (n = 312), however, reported impairment for both far and near vision. Impairment of distant vision increased progressively with age (P < 0.01). Persons with self-reported near vision impairment had elevated risk of functional disability in several IADLs and ADLs than those with out. Distant vision impairment was less associated with role limitations in both ADLs and IADLs.
CONCLUSION: The prevalence of self-reported distant visual impairment was high but that for near visual impairment was less than expected in this elderly African population. Impairment of near vision was found to carry with it a higher burden of functional disability than that of distant vision.