Heat Vulnerability Among Youth: Two Decades of Temperature-Driven Hospitalizations in Czechia

Abstract Background Extreme temperatures are responsible for increased mortality and morbidity. While temperature-related deaths are well documented, less is known about impacts on hospital admissions. Identifying vulnerable groups, particularly from Central and Eastern Europe is essential for designing adaptation strategies. This study quantifies temperature-related hospitalization risks across Czechia. Methods We used daily hospital admissions (n = 13 509 940) from 1998 to 2018, stratified by region, age, sex, and cause, and linked to daily mean temperature. We used a distributed lag non-linear model with a quasi-Poisson regression for each of the 14 regions, modeling the exposure-response curve. Long-term and seasonal trends were controlled with a natural spline of time (7 degrees of freedom per year), and day-of-week. The baseline relative risk (RR = 1) was defined at the median temperature (9.08 °C). Later, we pooled regional estimates using multivariate meta-analysis. Results At the 99th temperature percentile, all-cause hospitalizations rose (RR 1.07, CI: 1.05-1.09), with minimal regional heterogeneity. When data were disaggregated, children and adolescents (5-19 years (y)) emerged as the most vulnerable group to heat (RR 1.31, CI: 1.25-1.37), exceeding risks observed in infants (0-4y, RR 1.07, CI: 1.04-1.10) or adults (20-64y, RR 1.11, CI: 1.09-1.13). Unexpectedly, seniors showed declining hospitalizations during heat events (65-74y, RR 0.91, CI: 0.88-0.94; >75y, RR 0.93, CI: 0.90-0.96). Cardiovascular and respiratory admissions fell during heat, but respiratory disease admissions increased (RR 1.16, CI: 1.12-1.20) during extreme cold (1st percentile). Conclusions Extreme heat posed a disproportionate hospitalization burden on youth. Prioritizing youth-centered heat action plans could reduce hospitalizations and pressure on healthcare during extreme heat events. The elderly showed a counterintuitive decrease in hospitalizations during heat that needs further analysis. Key messages • Children and adolescents are at highest risk of hospitalization during extreme heat. • Hospitals must prepare for pediatric surge capacity during extreme heat.