Who is Most at Risk? Heat-Related Morbidity and Mortality among Individuals with Pre-Existing Chronic Diseases: Space-Time Stratified Analyses

We select patients with general and heat-related illness, specifically
individuals with pre-existing COPD, diabetes, hypertension, heart
failure, neurodegenerative, CKD and chronic mental health problems.
Individuals with CKD is selected based on estimated glomerular
filtration rate (eGFR<45), which corresponds to moderate to severe
CKD, including stages 3b, 4, and 5.17 Chronic mental health problems is defined by identifying patients diagnosed with specific ICPC-2 codes and prescribed medication treatment. We uses an aggregated daily number of counts spanning 2005-2019.

Extreme heat can have serious health effects, increasing the risk of
dehydration, cardiovascular strain, respiratory problems, and even
death. While majority of previous studies have examined the general
impact of heat on hospital admissions and mortality, fewer studies have focused on how pre-existing chronic diseases make individuals more at risk. Our study specifically investigates the impact of heat on general and heat-related illnesses as well as mortality among individuals with chronic diseases. Using long-term health records from general practitioners, we also conduct detailed subgroup analyses to understand how different factors modify heat-related health risks, which helps to identify population segments most vulnerable and who may need targeted interventions during extreme heat.

General- and heat-related illness and mortality