Determinants of blindness from glaucoma among patients receiving treatment: a retrospective cohort study in Enugu, Nigeria

Abstract

BACKGROUND: Irreversible blindness is the natural history of untreated glaucoma; however, a significant proportion of those receiving treatment are still blind. This study sought to identify the determinant factors responsible for blindness from glaucoma among those receiving treatment. METHOD: This retrospective cohort study collected data via chart review of glaucoma patients (N = 231) who attended eye clinics at a large government-owned or a privately owned health facility in Enugu, Nigeria, between October and December 2023. Visual acuity was used to determine whether the eyes met the criteria for blindness. The sociodemographic and clinical characteristics of glaucoma patients who were blind (105) and patients without blindness (126) were compared. Data analysis was performed via the statistical package for social sciences (SPSS) version 26. Binary logistic regression was used to identify determinants of blindness. RESULTS: The records of a total of 231 glaucoma patients were reviewed. One hundred and five (45.5%) patients were blind in at least one eye. The mean age was 61.1 ± 13.9 years (patients without blindness) and 63.6 ± 10.6 years (blind patients). Those living in urban areas (AOR = 0.49, 95%CI = 0.24-0.99), those with no visual impairment at presentation (AOR = 0.005, 95% CI = 0.000-0.055, p < 0.0001), those with mild to moderate visual impairment (AOR = 0.125, 95% CI = 0.06-0.277, p < 0.0001), and those with presenting IOP < 22 mmHg (AOR = 0.23, 95% CI = 0.09-0.546, p = 0.001) were significantly associated with a lower risk of blindness from glaucoma. However, being non-hypertensive was associated with a higher risk of blindness from glaucoma (AOR = 2.20, 95% CI = 1.16-4.18, p = 0.043). CONCLUSION: Among patients receiving treatments for glaucoma, living in non-urban areas, presenting with severe visual impairments, presenting with IOP > 22 mmHg, and being non-hypertensive increased the risk of blindness. Improving access to glaucoma care in non-urban areas, increasing awareness creation on screening for early detection and patient counseling may be profitable steps towards reducing vision loss from glaucoma.