Environment/Climate Change
Heatwaves and Health System Burden in Santiago: Disparities in Exposure Across Urban Zones (1992 – 2019). Estela Blanco* José Daniel Conejeros Estela Blanco Rayana Palharini Eduardo Undurraga
Background: Heatwaves (HWs) have become increasingly frequent and severe due to climate change, posing significant risks to urban populations and health systems. While studies globally have associated HWs with increased hospital admissions and emergency visits, the evidence from South America, particularly urban areas, remains limited. Furthermore, little is known about disparities in HW exposure across health zones within Latin America’s major urban centers.
Methods: This study examines the evolution of the health system burden from HWs in Santiago, Chile (1992–2019), and identifies disparities across health zones. Daily maximum air temperature was used to calculate HW metrics: 3 consecutive days exceeding 30°C, 90th, 95th, and 99th percentiles, and the Excess Heat Factor (EHF). Emergency visit data from the Chilean Ministry of Health (DEIS) were aggregated by municipality and year. Distributed lag linear models were applied to assess delayed HW effects.
Results: Preliminary results show temporal and spatial variability in HW exposure, with more frequent events in eastern and southern Santiago. Municipalities like Quilicura, Estación Central, and Cerrillos experienced up to 3 consecutive days above the 95th percentile (Figure 1). These vulnerable zones faced higher burdens during HWs, especially using EHF metrics, and showed the largest increases in emergency visits, with an RR of 1.21 (95% CI: 1.05–1.37). Findings highlight inequities in exposure and health outcomes, urging targeted interventions.
Conclusions: Our findings underscore the need for targeted public health interventions to mitigate the impacts of HWs, particularly in socioeconomically vulnerable areas. Incorporating diverse HW metrics, including air and land temperatures and radiation, provides a more comprehensive understanding impacts of extreme events on urban populations. This study highlights the importance of addressing climate-related health disparities as cities face increasing HW frequency.
