Prevalence, distribution and determinants of myopia in Owerri, Nigeria

Abstract

Background: Uncorrected myopia is a significant cause of visual impairment and avoidable blindness. Incidence of open-angle glaucoma has been shown to occur more often in myopia. This cross-sectional analytical study determined the prevalence, distribution and determinants of myopia in the adult population of Imo State, Nigeria with a view to establish a reference data for research purposes and future intervention in this locality. Materials and Method: A total of 3451 adults living in Owerri consisting of 2606 persons as test group and 845 persons as controls were randomly selected using standard optometric methods including subjective refraction. Results: Refractive error (ametropia) was found in 79.5% study and 76.8% control. Myopia was found in 23.4% study and 19.6% control. Highest prevalence of myopia was observed in females aged 40-49 years. Fifty percent of study and 68.1% of control group had myopia of -0.50DS to -3.00DS while 4.0% and 2.4% of study and control group respectively had myopic astigmatism. In all, 27.7% study and 16.2% control had myopia > 5.00DS. The highest degree of myopia found in this study was - 24.00DS. Conclusion: This study provided information on the prevalence, distribution and determinants of myopia in Owerri, Nigeria and the data could be a basis for improved visual health care in the south-eastern sub-region of Nigeria.