Is short-term exposure to heat associated with mental health compared to other conditions?

Background and Aim: Health impacts of heat exposure are increasingly important due to climate change. Anxiety and depression are common and understudied mental health conditions, possibly associated with heat exposure. We examined associations between short-term (5-day) apparent temperature and health visits for anxiety and/or depression in North Carolina. Methods: We linked electronic health records from a random sample of adults seen at University of North Carolina Healthcare System hospitals 2004-2018 in the EPA CARES resource with climate data from PRISM Climate Group. We examined 5-day mean apparent temperature (incorporating temperature and humidity) at the ZIP code level for patients diagnosed with anxiety and/or depression compared to first recorded visit for those with any other diagnosis. We used log binomial regression models adjusted for personal (age, sex, race, health insurance status), environmental (season, annual PM2.5 concentration, climate division) and neighborhood (median household income, percent Bachelor’s degree or more, percent urban) covariates. Results: We included 17,145 patients, 2219 of whom were diagnosed with anxiety and/or depression. Those with anxiety and/or depression were, on average, younger (46.4 vs 48.0 years), more likely to be female (69.7% vs 59.7%), and White (74.7% vs 62.4%), compared to those with other diagnoses. Mean five-day apparent temperature was 17.6 degrees C (SD 10.4). The prevalence of having a diagnosis of anxiety and/or depression was 1% higher per degree increase in five-day mean apparent temperature (PR 1.01, 95% CI 1.00, 1.02) compared to other diagnoses. Results were similar when limiting to anxiety, depression, and geographic region. Conclusions: We did not observe substantial associations between apparent temperature and anxiety or depression relative to other outcomes. Future studies should expand this work to larger areas with more temperature variability and consider mental health trends independent of other outcomes. This abstract does not reflect EPA policy. Keywords: climate, heat, mental health