Climate and the eye: Case-crossover analysis of retinal detachment after exposure to ambient heat

Retinal detachment is an important cause of visual loss, but the association with outdoor heat exposure has not been studied. Our objective was to determine the relationship between acute exposure to high outdoor temperature and risk of retinal detachment.

We analysed 14,302 individuals with inpatient procedures for retinal detachment from April through September between 2006 and 2013 in the province of Quebec, Canada. Using a time-stratified case-crossover study design, we examined the association of retinal detachment with outdoor summer temperature the preceding week. We estimated odds ratios (OR) and 95% confidence intervals (CI) for mean weekly temperature according to subtypes of retinal detachment (traction, serous, rhegmatogenous, breaks), and assessed associations by age and sex.

Exposure to elevated temperature the preceding week was associated with a higher likelihood of traction detachment, but not other forms of retinal detachment. Associations were stronger at <75 years of age in both men and women. Relative to 15°C, a mean weekly temperature of 25°C was associated with an OR for traction detachment of 2.71 (95% CI 1.56-4.71) before 55 years, 2.73 (95% CI 1.61-4.64) at 55-64 years, and 1.98 (95% CI 1.30-3.02) at 64-75 years.

Elevated outdoor temperatures may be associated with an increased risk of traction retinal detachment. In light of climate change, a better understanding of the impact of heat waves on the eye and other sensory organs is needed.