The Impacts of Climate Change on Human Health: Quantification of the Risk in Chile

Abstract

Background The association between temperature and mortality has been widely established in literature. The aim of this study is to quantify the premature deaths attributable to temperature variations (heat or cold) due to climate change in order to provide results that can be easily interpreted by policy makers. The focus of the study is the Chilean territory, an interesting country to analyze due to its extremely diverse climates.Methods We estimated the mortality risk attributable to temperature variation by fitting a standard time-series Poisson model for each of the main cities, controlling for pollution, influenza, trends and day of the week. Temperature and mortality association is estimated with a distributed lag non-linear model. Consecutively, we estimated the number expected deaths by 2050 for such mortality risks using temperature projections.Results Temperature is responsible for a 0.7% increase in future expected mortality. The largest impact is located in the central region, where up to 1% of additional deaths are expected to occur due to rising temperatures. Interestingly, the opposite is observed in some regions. For example, in the North, 3.3% fewer deaths are expected to occur during the winter months. The minimum mortality temperature (MMT) varied from the 60th percentile in the central region, to the 80th-90th in the northern and southern regions, where temperatures tend to be more extreme.Conclusions Main results show a high contribution of cold temperatures in risk, with exception of the extreme southern region. Temperature is responsible of a substantial fraction of future deaths, however, opposite to expected, in certain regions as temperatures rise, fewer deaths occur, mainly due to average temperature lying below the estimated MMT. The heterogeneity of the results highlights the need of geographical-based policies, evidencing important implications for the planning of public-health interventions related to climate change.