International Ophthalmology

, Volume 22, Issue 5, pp 293–298 | Cite as

Outdoor work and the risk of pterygia: a case-control study

  • Joan Khoo
  • Seang-Mei Saw
  • Karabee Banerjee
  • Sin-Eng Chia
  • Donald Tan


Aim: To investigate the relationship between outdoor work and pterygium formation in a hospital-based case-control study in Singapore. Method: Sixty-one patients with pterygium (49 males, mean age 54.2 years) and 125 controls (41 males, mean age 50.2 years), excluding patients with cataract and age-related macular degeneration presenting at outpatient clinics of the Singapore National Eye Centre were interviewed face-to-face with a standard questionnaire. Demographic data and information on outdoor work and eye protection, were collected. Results: Thirty-eight subjects (20.4%) were outdoor workers and 148 (79.6%) were indoor workers. Outdoor workers were more likely to be male smokers and alcohol drinkers with lower family income and higher sunlight exposure than indoor workers. The crude odds ratio for pterygiumin outdoor workers was 7.0 (95% confidence interval 3.2, 15.3). The adjusted odds ratio was 4.2 (95% confidence interval 1.7, 10.1). Conclusion: There is a statistically significant association between outdoor work and pterygium formation, which may be related to the higher exposure to sunlight and dust in outdoor workers. Efforts may be made to educate outdoor workers to wear proper equipment to protect their eyes against excessive sunlight.

epidemiology occupation pterygium sunlight 


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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • Joan Khoo
    • 1
  • Seang-Mei Saw
    • 2
  • Karabee Banerjee
    • 3
  • Sin-Eng Chia
    • 2
  • Donald Tan
    • 4
  1. 1.National University of SingaporeSingapore
  2. 2.Department of Community, Occupational and Family MedicineNational University HospitalSingapore
  3. 3.Department of OphthalmologyChangi General HospitalSingapore
  4. 4.Singapore National Eye CentreSingapore

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