Dementia and risks of temperature-related mortality and hospitalizations in Germany.

Background: Extreme temperatures are associated with negative health outcomes, in particular for older adults with pre-existing conditions. While climate change is expected to increase exposure to temperature levels that are detrimental for health, little is known about how dementia shapes vulnerability to extreme temperatures.

Methods: We leveraged repeated quarterly individual-level health claims from 2004 to 2019 on 250,000 individuals in Germany aged 50 years and above with information on key neurodegenerative diseases such as dementia. We linked data on the location of residence of these individuals with high resolution gridded meteorological data. In our empirical analysis, we applied an individual-level Fixed Effects model to estimate how temperature affects the single patient's probability of hospitalization and death, adjusted for seasonality and comorbidities.

Results: Our findings reveal that heat and cold exposure increase the risk of death. Conversely, the association between extreme temperatures and hospital admissions is more nuanced showing an increase only with cold exposure. Stratifying the analysis by individuals affected by dementia, we observe heat to increase mortality only for individuals with dementia and cold to determine an 8 times larger impact on them and a larger increase in hospitalization. Also, we observe individuals aged above 80 and with dementia do be the most at risk of death with exposure to cold and in particular heat.

Conclusion: Our study contributes to the growing body of evidence on the health impacts of climate change and emphasizes the need for targeted strategies to protect vulnerable groups, particularly patients with dementia, from adverse temperature effects.