Epidemiology and Risk Factors of Primary Open-Angle Glaucoma in the North East Geopolitical Zone of Nigeria: A Multi-Centre Study

Primary open-angle glaucoma (POAG) remains a leading cause of irreversible blindness in Nigeria, yet comprehensive epidemiological data from the North East geopolitical zone are largely absent from the literature. This study investigates the prevalence, incidence, and modifiable risk factors of POAG among adults aged 40 years and above across Borno, Adamawa, Yobe, Taraba, Bauchi, and Gombe States. A multi-centre cross-sectional study design will be employed, recruiting 1,200 participants from tertiary and secondary eye care facilities in each state using stratified random sampling. Glaucoma diagnosis will be based on comprehensive clinical evaluation including intraocular pressure measurement, optic disc assessment using optical coherence tomography (OCT), and automated visual field testing using Humphrey perimetry. A detailed sociodemographic and medical history questionnaire will document known risk factors including age, ethnicity, family history, systemic hypertension, and diabetes mellitus. Multivariate logistic regression will identify independent risk predictors. The study fills a significant research gap in North East Nigeria, where armed conflict and limited healthcare infrastructure have historically constrained population-based eye health research. Findings will be disseminated to the Federal Ministry of Health and state-level health authorities to support evidence-based glaucoma control programs. This study will contribute substantially to the epidemiological literature on POAG in sub-Saharan Africa and advance targeted prevention efforts in a previously understudied region. Keywords: primary open-angle glaucoma, epidemiology, North East Nigeria, risk factors, optical coherence tomography