Magnitude and causes of blindness and low vision in Anambra State of Nigeria (results of 1992 point prevalence survey).

A survey to determine the prevalence and causes of blindness in Anambra State of Nigeria was conducted. The aim was to provide baseline data for the planning, implementation and evaluation of both the state's and the National Programme for Prevention of Blindness. A multistage cluster random sampling technique was used. The World Health Organization/Prevention of Blindness (WHO/PBL) Eye Examination Record Form was used. The WHOs definitions of blindness and low vision were adopted for the analysis. The prevalence of blindness in the state is estimated to be 0.33% +/- 0.27%. Visual acuity of from 3/60 to less than 6/60 has a prevalence of 0.41% +/- 0.30% while visual acuity of from 6/60 to less than 6/18 has a prevalence of 0.67% +/- 0.39. There are equal numbers of blind males as females, although the prevalence among males is 0.44% +/- 0.26% while among females it is 0.24% +/- 0.15%. Most of the blind are above 50 y of age with prevalence of blindness in this age group being 2.62% +/- 1.31% (3.27% +/- 2.1% for males and 2.02% +/- 1.58% for females). Cataract caused most of the blindness (70.59%), followed by glaucoma (17.65%). Macular degeneration is becoming important (5.88%) while obvious infective causes are rare. Errors of refraction are important public eye health care problems. Methods of tackling the cataract problem (both backlog and incident), and other eye health needs within the primary eye/health care are recommended. The need to extend refraction services to the rural areas is emphasized.