Contribution of refractive errors to vision impairment in the Ashanti Region, Ghana.

Abstract

Purpose: To determine the prevalence and causes of vision impairment with particular emphasis on uncorrected refractive error (URE) in Ashanti region, Ghana. A baseline vision impairment study in the Ashanti region is necessary to effectively plan for refractive services and blindness prevention strategies. Methods: A cross-sectional multistage cluster sampling was conducted in 24 communities in Ashanti region, Ghana. A total of 1420 participants aged 18 years and above were enumerated using a modified Rapid Assessment of Vision impairment (RAVI) protocol. This was limited to unaided visual acuity (VA) using a Snellen chart at a distance of 6 meters, near binocular visual acuity and direct ophthalmoscopy for all participants after obtaining an informed consent. The VA was repeated using a pinhole for participants with VA ≤ 6/12. A non-cycloplegic refraction was done for those whose pinhole VA improved. Near vision refraction was also assessed for each participant whose near vision was less than N8. Simple proportions were used to compute the prevalence of vision impairment and refractive error in the studied population. The results were analyzed using STATA 11. Results: One thousand three hundred (1300) of those enumerated (1420), participated in the study, a response rate of 91.5%. The mean age of the participants was 46.29 (CI 95% 45.29-47.29). The minimum age was 18 years and the maximum 99 years. Prevalence of vision impairment was 16.15% (n= 210, 95% CI, 14.15 – 18.16). Refractive error was the leading cause of vision impairment with 47.14% (n = 99, 95% CI of 40.33 - 53.9) Conclusion: Refractive error was the main cause of visual loss in Ashanti region, Ghana.