Incidence of Primary Open-Angle Glaucoma at the Flamboyants Communal Medical Center of Conakry, Guinea

Abstract

Background: Primary Open-Angle Glaucoma (POAG) is a chronic, progressive optic neuropathy of multifactorial origin defined by alterations in the visual field, progressive loss of optic nerve fibers and ganglion cells, and an open iridocorneal angle in gonioscopy. It is the world’s leading cause of irreversible blindness. There is no epidemiological study in Guinea that allows us to locate the real level of the problem. The objective of this study is to determine the hospital incidence of POAG at the Centre Médical Communal (CMC) in the Flamboyants. Patients and Method: This was a descriptive cross-sectional study with a prospective collection for one year, from April 1, 2020 to March 31, 2021, in patients aged at least 40 years, received in consultation at the CMC in the Flamboyants. The diagnostic criterion for a new case of glaucoma was the presence in a patient of the following two signs: (excavation of the optical disc C/D ≥ 0.5 and alteration of the visual field) with an open angle at least stage 4 of the Shaffer and Etienne classification associated or not with ocular hypertonia and having never received anti glaucoma treatment. We described variables related to sociodemographic characteristics, visual acuity, intraocular pressures, papillary excavations, and visual field surveys. Informed consent from patients was sought and obtained. The confidentiality of the files was guaranteed. Results: 68 new cases of POAG were diagnosed out of 3220 consultations, an incidence rate of 2.11%. The average age was 58.2 years (10.64 with a male predominance of 63.23%. A family history of glaucoma was present in 11.36% of cases. Visual acuity was poor < 1/10 in 79 eyes/136, average between 1/10 and 3/10 in 11 eyes/136, and good ≥ 3/10 in 46 eyes/136. The mean intraocular pressure (IOP) was 26.5 mm Hg in the right eye and 25.9 mm Hg in the left eye with extremes of 18 and 38 mm Hg. The cup/disk ratio was above 0.5 in 97.1% at OD and 95.58% at OG. The visual field was impaired in all patients. Conclusion: This study has shown us that POAG in our environment is relatively common, early onset, and rapidly evolving. The implementation of a rapid and reliable screening strategy by the Eye Health Program will make it possible to manage glaucoma from the earliest stages.