Prevalence and predictors of keratoconus among patients attending tertiary eye care facilities in Malawi: A hospital-based study

Background Keratoconus (KC) is a progressive corneal ectasia and a significant cause of visual impairment globally. Despite its clinical significance, the epidemiological profile and associated risk factors for KC remain poorly defined in Sub-Saharan Africa, with a particular paucity of data from Malawi. This study was undertaken to estimate the prevalence of KC and to identify associated risk factors among patients presenting to two major tertiary referral hospitals in Malawi. Method A retrospective, cross-sectional study was conducted using patient records from Mzuzu Central Hospital in the Northern Region (n = 2,730) and electronic health records from Kamuzu Central Hospital in the Central Region. (n = 6,555). Data extraction included demographic details, clinical diagnoses of KC, spectacle use, and the presence of allergic conjunctivitis. Prevalence estimates were calculated per 1,000 population. To determine independent risk factors, multivariate logistic regression analysis was conducted, adjusting for potential confounders such as age and gender. Results The prevalence of KC was significantly higher in the Northern Region, estimated at 3.7 per 1,000 population, compared with 0.9 per 1,000 in the Central Region. A strong male predominance was evident, with 70% of cases. In multivariate analysis, spectacle wear for myopia correction emerged as the most significant predictor, conferring an adjusted odds ratio (aOR) of 373.4 (95% CI: 46.6–2991.0, p = 0.001). Allergic conjunctivitis was also identified as an independent risk factor (aOR = 4.9, 95% CI: 1.4–17.3, p = 0.014). In contrast, neither age nor gender demonstrated statistically significant associations with KC in the adjusted model. Conclusion This study demonstrates a substantial and regionally heterogenous burden of keratoconus in Malawi. The findings highlight spectacle use not solely as a corrective intervention but as a critical proxy indicator for advanced, undiagnosed KC in resource-limited settings. This observation provides a practical, high-yield strategy for integrating targeted screening into existing refractive care services. Enhancing clinical vigilance based on these risk factors is essential for facilitating early detection and timely management, thereby reducing the risk of KC-related blindness in Malawi and comparable low-resource contexts.