Nine-Year Incidence and Risk Factors for Pterygium in the Barbados Eye Studies

Purpose: To present 9-year incidence data and associated risk factors for pterygium among black participants in the Barbados Eye Studies. Design: Population-based incidence study. Participants: A total of 1888 black participants, aged 40 to 84 years, who were free of pterygium at baseline and received an ophthalmologic study examination at the 9-year follow-up. Methods: Age and sex-specific 9-year incidence of pterygium is presented. Risk factors were initially identified using Mantel-Haenszel analyses, and significant factors (P<0.10) were subsequently included in multivariate logistic regression models. Odds ratios (OR) and 95% confidence intervals (CI) are provided. Main Outcome Measures: Development of pterygium, defined as the presence of a raised fleshy growth that crosses the limbus and encroaches onto the clear cornea. Results: The 9-year incidence of pterygium was 11.6% (95% CI, 10.1-13.1), with no clear pattern with increasing age and no statistically significant differences between genders. Multivariate logistic regression analyses indicated that having a lifetime outdoor job location was positively associated with the development of pterygium (OR = 1.51; 95% CI, 1.05-2.16), whereas darker skin color (OR = 0.67; 95% CI, 0.46-0.97) and use of any prescription lenses (OR = 0.58; 95% CI, 0.42-0.81) were found to be protective factors. Conclusions: The incidence of pterygium was high in this population, for an average of 1.3% per year. Working outdoors increased the risk 1.5-fold, whereas having a darker skin complexion and using eyewear for either reading or distance substantially decreased the risk of developing pterygium. These data suggest that absorption of ultraviolet light plays a role in this condition and that preventive strategies are needed to decrease the burden of pterygium development in this and other populations. Financial Disclosure(s): The authors have no proprietary or commercial interest in any materials discussed in this article.