Long-Term Impact of Environmental Public Health Disaster on Health System Performance: Experiences from the Graniteville, South Carolina Chlorine Spill

Objectives: In the aftermath of an environmental public health disaster (EPHD) a healthcare system may be the least equipped entity to respond. Preventable visits for ambulatory careYsensitive conditions (ACSCs) may be used as a population-based indicator to monitor health system access postdisaster. The objective of this study was to examine whether ACSC rates among vulnerable subpopulations are sensitive to the impact of a disaster. Methods: We conducted a retrospective analysis on the 2005 chlorine spill in Graniteville, South Carolina using a Medicaid claims database. Poisson regression was used to calculate change in monthly ACSC visits at the disaster site in the postdisaster period compared with the predisaster period after adjusting for parallel changes in a control group. Results: The adjusted rate of a predisaster ACSC hospital visit for the direct group was 1.68 times the rate for the control group (95% confidence interval [CI] 1.47Y1.93), whereas the adjusted ACSC hospital rate postdisaster for the direct group was 3.10 times the rate for the control group (95% CI 1.97Y5.18). For ED ACSC visits, the adjusted rate among those directly affected predisaster were 1.82 times the rate for the control group (95% CI 1.61Y2.08), whereas the adjusted ACSC rate postdisaster was 2.81 times the rate for the control group (95% CI 1.92Y5.17). Conclusions: Results revealed that an increased demand on the health system altered health services delivery for vulnerable populations directly affected by a disaster. Preventable visits for ACSCs may advance public health practice by identifying healthcare disparities during disaster recovery.