Spatial analysis between particulate matter and emergency room visits for conjunctivitis and keratitis.

Background: The concentration of particulate matter in the air varies depending on the region because it is lightweight and generated from a variety of sources. To assess the relationship between particulate matter and eye disease, this study analyzes the concentration data obtained from spatial analysis of particulate matter and emergency visit data.

Methods: The study included 769 residents of Daegu, Korea who had visited an emergency room for the problem of conjunctivitis or keratitis. Concentrations of PM and other air pollutants were obtained from the Korean Ministry of the Environment. PM concentrations and the number of patients from each of 143 administrative dongs (sub-municipal level administrative units) of the city of Daegu were obtained using spatial analysis. The patient distribution and PM concentration were mapped for comparison, and their relationship was examined using scatter plot, regression analysis, and the independent sample t-test.

Results: The number of patients with conjunctivitis and keratitis was significantly higher in the regions of the top 20% areas than the bottom 20% areas in terms of PM concentration. The distribution of PM concentration and number of patients was visually similar on the map. The concentration of PM and the number of patients showed a dose-response relationship. When the concentrations of other air polluta9nts were controlled for, the numbers of conjunctivitis and keratitis patients were 0.04 per 1000 ER patients and 0.10 per 1000 ER patients, respectively.

Conclusion: As PM is associated with the prevalence of conjunctivitis and keratitis, measures to reduce particulate matter through environmental methods are needed.