Evidence for improving services for glaucoma in Nigeria: Epidemiology, ophthalmologists' practice pattern, patients' access to care and community experiences of glaucoma.

Glaucoma is the second leading cause of blindness worldwide. Africa region has the highest burden of glaucoma and glaucoma blindness.When diagnosed early and appropriate treatment sustained, blindness from glaucoma is avoidable.

The Nigeria national blindness and visual impairment survey (NBS), with >13,500 people aged≥ 40 years examined, estimated the prevalence of blindness as 4.2% (95%CI 3.8-4.6%).16.7% was due to glaucoma, the leading cause of irreversible blindness and functional low vision. There are insufficient population-based glaucoma studies in Africa;!and the NBS provided the largest dataset in Africa from which data on glaucoma could be derived.

In this study, analysis of the NBS data using established criteria from the International Society of Geographical and Epidemiological Ophthalmology showed high prevalence of glaucoma (5.02%; 95%CI 4.60-5.47%): undiagnosed in 94%; and open-angle glaucoma (OAG) in 86%. One -in -five persons with glaucoma were blind. Increasing age and higher intraocular pressure were independent risk factors for OAG; and some ethnic groups were more at risk. Glaucoma blindness was associated with socioeconomic deprivation, reflecting poor access to care. These findings underscored the high level of need for optimal glaucoma services. Information about glaucoma management obtained from 153 practising Ophthalmologists in Nigeria highlighted patient-related challenges of late presentation with advanced disease and poor compliance to treatment; and additional constraints due to inadequate access to equipment for diagnosis and treatment. In the qualitative study, we sought to understand access to glaucoma care and determine why people with glaucoma are presenting late for treatment. We found barriers of access to care which could be explained as evidence of structural inequalities associated with coping mechanisms and distinct social suffering. This study provided data required to develop evidence-based strategy for control of glaucoma blindness by improving glaucoma services in Nigeria. These data could also have implications to other Sub Saharan African countries with similar socioeconomic and ecological characteristics.