Abstract
Purpose :
To investigate whether daily changes in level of ambient air pollution is associated with an increased risk of central retinal artery occlusion (CRAO).
Methods :
Patients newly diagnosed with CRAO between 2001-2010 were identified from the Taiwan National Health Insurance Research Database. The concentrations of air pollutants including PM2.5, PM10, nitrogen dioxide (NO2), sulfur dioxide (SO2) and ozone (O3) were measured at a monitoring station in each district in Taiwan. The time-stratified case-crossover study design was used to assess the association between the risk of CRAO and each air pollutant level in the days preceding each event.
Results :
A total of 190 patients with CRAO were enrolled in this study. The mean age was 64.9 years (standard deviation, 14.1 years) and 59.5% of them were male. The estimated odds ratio of CRAO onset was 1.15 (95% CI, 1.01-1.30; p=0.03) per 1 ppb increase in NO2 levels following a 4-day period. The increase in risk was greatest within 2 to 3 days of exposure to NO2 (OR, 1.11; 95% CI, 1.01-1.21; p=0.03 and OR, 1.15; 95% CI, 1.03-1.28; p=0.01 on 2 and 3 day before onset, separately). The transient concentration of the other air pollutants including PM2.5, PM10, SO2 and O3 showed no significant on impact on the occurrence of CRAO in this study.
Conclusions :
These results suggest that exposure to NO2 levels may increase the risk of CRAO within days of exposure.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.