Who among the elderly is most vulnerable to exposure and health risks of PM2.5 from wildfire smoke?

Wildfires burn over 7 million US acres annually, according to the US Forest Service. Little is known regarding which subpopulations are more vulnerable to health risks from wildfire smoke, including fine particles. We estimated exposure to fine particles specifically from wildfires and associations between wildfire-specific fine particles and respiratory hospital admissions for subpopulations > 65 years in the Western US (2004-2009). Higher fractions of Blacks and people in urban counties and in California are exposed to > 1 smoke wave (high-pollution episodes from wildfire smoke) compared to other populations. Risk of respiratory admissions on smoke-wave days compared to non-smoke-wave days increased 10.4% (95% confidence interval: 1.9%, 19.6%) for females and 21.7% (95% confidence interval: 0.4%, 47.3%) for Blacks. Findings suggest that increased risk of respiratory admissions from wildfire smoke was significantly higher for females than males (10.4% versus 3.7%) and Blacks than Whites (21.7% versus 6.9%), and, although associations were not statistically different, lower-education counties than higher-educated counties (12.7% versus 6.1%). Our study raised important environmental justice issues that can inform public health programs and wildfire management. As climate change increases the frequency and intensity of wildfires, evidence on vulnerable subpopulations can inform disaster preparedness and understanding of climate change consequences.