Pterygium and associated factors among adults: a hospital-based prospective study

Abstract

Introduction: The aim of this hospital-based study was to assess the prevalence and associated factors of pterygium among adult patients visiting the Ophthalmology Outpatient Department (OPD) in the Jigme Dorji Wangchuck National Referral Hospital (JDWNRH), Thimphu. Methods: A cross sectional study was carried out in the ophthalmology OPD in the national referral hospital, Thimphu from 1st January, 2018 to 31st December, 2018, during which 1599 adult patients were selected through systematic random sampling. Results: The prevalence of pterygium was 12.8% (95% CI: 11.2 -14.5). Among 271 eyes with pterygium, the distribution of grade 1, grade 2 and grade 3 pterygium was 34.7%, 56.1% and 9.2% respectively. Pterygium was most common in the age group of 36-55 years. The significant factors associated with pterygium were age group, occupation and usage of sunglasses. Individuals who were 36-55 years (adjusted OR 2.70, 95% CI 1.82-4.0) and >55 years (adjusted OR 2.17, 95% CI 1.34-3.50) had significantly higher risk than 18-35 years (p< 0.002), and not using sunglasses (adjusted OR 1.97, 95% CI1.17-3.33, p = 0.007) significantly increased the risk of pterygium. Indoor occupation, particularly being a student was protective against pterygium (OR 0.08, 95% CI 10.02-0.33, p< 0.001). Only 14.1% used sunglasses and among them, 27.6% were aware that sunglasses can protect from ultraviolet radiation. Conclusion: This study found a high prevalence of pterygium among adults aged 18 years and above. Those aged 36-55 years and an occupation involving outdoor activities were affected more. Encouraging usage of sunglasses may reduce pterygium