Title : Factors associated with primary open angle glaucoma in a Nepali population Jiri Eye Study: Oculo genetic study
Abstract:
Introduction: Glaucoma is the second most common cause of blindness with primary open-angle glaucoma (POAG) as one of the leading causes.
Objective: To study the ocular and systemic associated factors that lead to the development of primary open-angle glaucoma
Methodology: This is population-based, analytical cross-sectional, oculo-genetic study conducted in a single pedigree from 2015 to 2018. Among the total 2042 study participants ≥18 years of age were included using convenience sampling, 37 were diagnosed with POAG. For comparative analysis, age and gender matched controls without glaucoma were selected in a 1:4 ratios from the same population. Patients with primary angle closure glaucoma, secondary glaucoma, pseudoexfoliation, glaucoma suspects, acute ocular infections, ocular tumors and trauma were excluded. A detailed ocular and systemic history of HTN, DM, alcohol intake, smoking and tobacco chewing was taken. Height, weight, blood pressure and the BMI status of an individual was measured. Ophthalmic examination included measurement of visual acuity, refraction, slit lamp biomicroscopy, intraocular pressure, gonioscopy and dilated fundus examination. Ocular biometry, keratometry, anterior and posterior segment oct, and Visual field assessment, was done to measure axial length, lens thickness, anterior chamber depth, and corneal curvature radius, central corneal thickness, cup disc ratio, retinal nerve fibre layer thickness, mean and pattern standard deviation.
Results: Overall prevalence of POAG was 1.81% among the total 2042 participants above the age of 18 years, 2.53% in 30 years and above and 3.41% in 40 years and above. There was an increase in the prevalence after the age of 40 years and the highest was noted in the age group of 70 years to 79 years. (males 0.98%, female 0.83%). The mean IOP was 15.34 (±3.74) mmHg. POAG was associated with increased intraocular pressure (p = 0.019), wider Anterior chamber angle (P<0.004), increased vertical cup disc ratio (p <0.001), retinal nerve fibre layer thinning (p <0.001) and increased pattern standard deviation (p <0.001), and decreased mean deviation (p = 0.020) in Visual Field and there was no correlation between CCT and IOP. Other factors such as BMI, DM, HTN, family history of glaucoma, smoking, alcohol consumption, tobacco chewing, refractive error, CCT, CCR, ACD, AL, lens thickness, and iris thickness were not associated.
Conclusion: Identifying the factors associated with POAG and adopting screening strategies for its early detection will prevent blindness in this population
