ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on X

Kidney Week

Please note that you are viewing an archived section from 2019 and some content may be unavailable. To unlock all content for 2019, please visit the archives.

Abstract: SA-PO1059

Exposure to Wildfire Smoke Increases Mortality in US Hemodialysis Patients

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis

Authors

  • Xi, Yuzhi, Oak Ridge Institute for Science and Education, United States Environmental Protection Agency, NHEERL, Chapel Hill, North Carolina, United States
  • Kshirsagar, Abhijit V., University of North Carolina, Chapel Hill, North Carolina, United States
  • Wade, Timothy J., United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
  • Richardson, David, University of North Carolina, Chapel Hill, North Carolina, United States
  • Brookhart, M. Alan, University of North Carolina, Chapel Hill, North Carolina, United States
  • Rappold, Ana G., United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
Background

Wildfires are a significant source of fine particulate matter (PM2.5) that is causally related to mortality. Our objective is to assess the effect of wildfire-PM2.5 on daily mortality among patients receiving chronic in-center hemodialysis (HD) in the US.

Methods

From the United States Renal Data System (USRDS), we identified patients who 1) had Medicare as primary payer, 2) survived first 3 months of dialysis, and 3) visited dialysis clinics within the 627 counties impacted by at least one large wildfire between 2008-2012. Outcomes were daily all-cause mortality and all-cause mortality by place of death (clinical and nonclinical). Exposure was county-level daily wildfire-PM2.5 concentrations. We tested the association of wildfire-PM2.5 exposure to daily mortality using time series analysis, while controlling for time-dependent factors (temperature, etc.) and by design for time-independent characteristics (demographics and comorbidities). The immediate (same day) effect and the cumulative effect of 1, 7, 14, and 30 days of the exposure to wildfire-PM2.5 on mortality were expressed as adjusted rate ratios (RR) per 10 mg/m3increase in PM2.5.

Results

Among 48,454 deaths, the RR of the same day effect on all-cause mortality was 1.04 (95%CI: 1.01-1.07) and the cumulative effects of 1, 7, 14, and 30 days following the exposure were 1.05 (1.02-1.08), 1.07 (1.03-1.11), 1.06 (1.01-1.10), and 1.07 (1.01-1.12), respectively. For all-cause death occurring in non-clinical settings, the RR of the same day effect was 1.07 (95%CI: 1.02, 1.12), and the respective RRs of cumulative effect were 1.07 (95%CI: 1.02, 1.12), 1.09 (95%CI: 1.02, 1.15), 1.07 (95%CI: 1.00, 1.15), and 1.09 (95%CI: 1.01, 1.18).

Conclusion

Wildfire-PM2.5 exposure was associated with a ~5% increase in daily all-cause mortality rate among HD patients. These deaths occurred in non-clinical settings such as homes, where exposure to PM2.5 may be exacerbated. The first of its kind study highlights the impact of environmental exposures on a fragile population, and the need for additional research. This abstract does not reflect EPA policy.

Funding

  • Other U.S. Government Support