Projections of temperature-associated mortality risks under the changing climate in an ageing society

Objectives: This study aimed to project future temperature-associated mortality risk and additional deaths among Taiwan's elderly (aged >65 years) population. Study design: This study investigated retrospective temperature-mortality risk associations and future mortality projections.Methods: A distributed lag non-linear model and random effect meta-analyses were employed to assess the risk of daily temperature-associated deaths in all-cause, circulatory, and respiratory diseases. Using the sta-tistical downscaling temperature projections of the Representative Concentration Pathways (RCPs; i.e. RCP2.6, RCP6.0 and RCP8.5), future risk of mortalities were projected among the elderly for 2030-2039, 2060-2069 and 2090-2099, with a 30%, 40% and 50% expected increase in elderly population proportions, respectively. Results: The baseline analysis from 2005 to 2018 identified that Taiwan's population is more vulnerable to cold effects than heat, with the highest cold-related mortality risk being attributed to circulatory diseases, followed by all-cause and respiratory diseases. However, future projections suggest a declining trend in cold-related mortalities and a significant rise in heat-related mortalities under different RCP scenarios. Heat-attributable mortalities under the RCP8.5 scenario by 2090-2099 would account for almost 170,360, 36,557 and 29,386 additional annual deaths among the elderly due to all-cause, circu-latory and respiratory diseases, respectively. Heat-attributable all-cause mortalities among the elderly would increase by 3%, 11% and 30% under RCP2.6, RCP6.0 and RCP8.5, respectively, by 2090-2099.Conclusions: The findings of this study provide predictions on future temperature-related mortality among the elderly in a developed, ageing society with a hot and humid climate. The results from this study can guide public health interventions and policies for climate change and ageing society-associated health risks.& COPY; 2023 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study projected future temperature-associated mortality risk and additional deaths among the elderly population in Taiwan. The results indicate that heat-related mortality is expected to increase significantly under different Representative Concentration Pathways (RCPs) scenarios, particularly under high emission scenarios. These findings can guide public health interventions and policies for climate change and ageing society-associated health risks.