Association Between US Wildfires and Health Care Utilization for Acute Rhinosinusitis

Wildfires (WF), a major contributor to air pollution including ambient particulate matter 2.5 (PM2.5), have been shown to increase the risk of developing sinonasal diseases. This study assesses the impact of WF on health care claims for acute rhinosinusitis (ARS).

Utilizing national WF geospatial records and EPA-based smoke-PM2.5 databases, we identified core-based statistical areas (CBSAs) affected by WF >50,000 acres, occurring between 2014 and 2019. We correlated WF events with MarketScan health care claims data, calculating daily outpatient visit proportions relative to total visits per CBSA for ARS, chronic rhinosinusitis (CRS), rhinitis, and asthma. We calculated risk ratios (RRs) by comparing visit proportions in pre-WF versus post-WF periods, adjusted for seasonality by comparison to non-WF periods in the same CBSAs. Cross-correlation (CC) analysis was conducted to determine the temporal relationship between daily smoke-PM2.5 and ARS-visit proportions.

Sixteen WFs events from nine CBSAs were captured, yielding 2.22 M claims. ARS visit proportions increased in the 2 months post-WF periods, with an RR of 1.17 (confidence interval = 1.12‒1.22). CRS and rhinitis showed no significant increase in RR. Control analysis (2.08 M claims) yielded an RR of 0.97 (0.93‒1.082) for non-WF ARS-visit proportions. CC analysis indicated a significant correlation (0.4 ± 0.04; p < 0.001) with a lag of 33 ± 3 days.

WF smoke exposure is associated with increased health care utilization for ARS in the 2 months post-exposure.