Geographic and climatic factors associated with exfoliation syndrome

Arch Ophthalmol. 2011 Aug;129(8):1053-60. doi: 10.1001/archophthalmol.2011.191.

Abstract

Objective: To identify geographic and climatic risk factors associated with exfoliation syndrome (ES).

Methods: A retrospective study of 626 901 eye care recipients, dating from 2001 to 2007 from 47 US states in a managed care network. Incident ES cases-patients (N = 3367) were identified by using billing codes. We assessed the risk of ES by geographic latitude tier in the continental United States and assigned state-level climatic data (eg, ambient temperature, elevation, and sun exposure) according to patients' residential location. The hazard of ES was calculated by using multivariable-adjusted Cox proportional hazards regression models.

Results: Compared with middle-tier residence, northern-tier residence (above 42°N) was associated with an increased hazard of ES (adjusted hazard ratio [HR], 2.14; 95% confidence interval [CI], 1.94-2.35). Southern-tier (below 37°N) was associated with a reduced hazard of ES (HR, 0.83; 95% CI, 0.75-0.93). Excluding whites did not change these associations. After adjustment for joint environmental effects, for every 1° increase in July high temperature, the hazard of ES decreased by 9% (HR, 0.91; 95% CI, 0.89-0.93); for every 1° increase in January low temperature, the hazard decreased 3% (0.97; 0.96-0.98). For each additional sunny day annually, the hazard increased by 1.5% (HR, 1.02; 95% CI, 1.01-1.02) in locations with average levels of other climatic factors.

Conclusion: Ambient temperature and sun exposure may be important environmental triggers of ES.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Climate*
  • Exfoliation Syndrome / epidemiology*
  • Female
  • Geography*
  • Glaucoma, Open-Angle / epidemiology
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Proportional Hazards Models
  • Retrospective Studies
  • Risk Factors
  • United States / epidemiology