Prevalence of and Risk Factors for Pterygia in a Rural Northern Chinese Population

Abstract

Purpose: To determine the prevalence of and associated risk factors for pterygia development in a high-latitude-dwelling Northern Chinese population.

Methods: A prospective population-based survey was conducted between November 2008 and July 2009. A stratified, clustered, randomized sampling procedure was used to select 8445 subjects, aged ≥18 years, all with diagnosed, graded pterygia. Risk factors associated with the occurrence of pterygia were evaluated according to logistic regression models.

Results: A total of 8445 residents (aged 18–94 years) from the Heilongjiang Province, China, participated in the study. Of these, 208 (2.5%) had at least one diagnosed pterygium. The prevalence of bilateral pterygia was 1.2% (95% confidence interval, CI, 1.0–1.4%). According to multivariable analysis, pterygia were significantly more likely to occur in persons aged 70–94 years than in those aged 18–39 years (odds ratio, OR, 29.0, 95% CI 13.6–61.6, p < 0.01). Pterygia were significantly associated with male sex (OR 1.9, 95% CI 1.4–2.6, p < 0.01) and outdoor work (OR 1.8, 95% CI 1.2-2.6, p < 0.01). Multivariable analysis indicated that pterygia were not associated with smoking status (OR 1.0, 95% CI 0.8–1.4) or alcohol intake (OR 1.0, 95% CI 0.7–1.4, p > 0.05).

Conclusions: This study details the occurrence of and risk factors for pterygia in a Chinese population residing in a rural, high-latitude, cold-climate area of Northern China. The primary risk factors for pterygia were age, male sex, and outdoor work.

• Cold climate
• population-based
• prevalence
• pterygium
• risk factor

Acknowledgments

We acknowledge local government officials and the workers at the local township clinics for their painstaking and enthusiastic work. We thank the Mingshui People’s Hospital for its organizational support. We are also grateful to the participants for their generous participation in the survey.