biostudies-literatureUnknown6(11)Casey JA<h4>Importance</h4>January 2025 brought devastating wildfires to Los Angeles (LA) County, California, causing poor air quality, destroying homes and businesses, and displacing thousands of people.<h4>Objective</h4>To promptly determine if the January 2025 LA fires increased outpatient acute health care utilization.<h4>Design, setting, and participants</h4>This cohort study assessed electronic health care records of 3.7 million members of Kaiser Permanente Southern California (KPSC) who met enrollment criteria. Of those, 305 258 were highly exposed and 1.4 million were moderately exposed. KPSC serves 4.7 million people across 10 counties. Analyses were conducted January-June 2025.<h4>Exposures</h4>Highly exposed members were those who resided in a census tract within 20 km of burn zones, anJAMA health forume254632https://www.ebi.ac.uk/biostudies/studies/S-EPMC12658665biostudies-literatureThe 2025 Los Angeles Wildfires and Outpatient Acute Health Care Utilization.PMC12658665McBrien HCasey JADey AKWilner LBFrankland TBGu YMTartof SYChen CFlores NMLee GSBenmarhnia TSchwarz LfalseThe 2025 Los Angeles Wildfires and Outpatient Acute Health Care Utilization.<h4>Importance</h4>January 2025 brought devastating wildfires to Los Angeles (LA) County, California, causing poor air quality, destroying homes and businesses, and displacing thousands of people.<h4>Objective</h4>To promptly determine if the January 2025 LA fires increased outpatient acute health care utilization.<h4>Design, setting, and participants</h4>This cohort study assessed electronic health care records of 3.7 million members of Kaiser Permanente Southern California (KPSC) who met enrollment criteria. Of those, 305 258 were highly exposed and 1.4 million were moderately exposed. KPSC serves 4.7 million people across 10 counties. Analyses were conducted January-June 2025.<h4>Exposures</h4>Highly exposed members were those who resided in a census tract within 20 km of burn zones, an2025-01-01T00:00:00Z2025 Nov2026-06-05T21:42:37.28Z2026-05-22T03:15:32.345ZS-EPMC126586654129637610.1001/jamahealthforum.2025.4632