Causes and prevalence of non-vision impairing ocular conditions among a rural adult population in SW Uganda

Abstract

Information is scanty about the extent of ocular morbidity in developing countries, particularly for non-vision impairing conditions (NVIC), although these constitute the majority of consultations in eye clinics. We have conducted a survey to determine the prevalence and causes of NVIC in a Ugandan adult population and compared our findings with the work pattern of the district hospital. Adults were screened using Snellen's illiterate E chart and those found with visual impairment (acuity less than 6/18) in either eye were referred to a low-vision clinic, and those with obvious ocular disease or symptoms, but without visual impairment, to an outreach clinic. A total of 2886 (53%) out of 5479 adults were screened. Of these, 257 (8.9%) were referred to the outreach clinic, of whom 173 (67%) attended. Of those attending the low-vision clinic 83% had visual impairment confirmed, and 92% of those attending the outreach clinic were confirmed not to have visual impairment. The four commonest NVIC observed at the outreach clinic were: presbyopia (48%), allergic conjunctivitis (20%), early cataract (9%) and infective conjunctivitis (8%), the same conditions as those most commonly seen at the district hospital. In this community, over 80% of NVIC are caused by four conditions which are potentially either correctable, operable or treatable. Training health workers to recognise and treat these conditions would serve the great majority of eye patients. Hospital activity data can be used cautiously to assess the relative frequency of NVIC in the community.