Abstract P644: Average Daily Temperature Fluctuation and Hospitalizations and 30-Day Mortality for Stroke and AMI

Abstract

Background: Daily average temperature is associated with increased hospitalizations and mortality for vascular conditions, but it is unclear if daily temperature variation is also associated with these outcomes. We assessed the relationship of daily temperature fluctuations with stroke and AMI hospitalizations and mortality in the elderly. Methods: We identified fee-for-service Medicare beneficiaries aged ≥65 y with a primary discharge diagnosis of ischemic stroke or AMI in 2014-2015. Daily temperature data from the National Centers for Environmental Information were linked with Medicare beneficiary data by county and admission date. We fit a Poisson model for the relationship between daily temperature range (county daily maximum minus minimum) and 30-day hospitalizations, adjusted for season and patient demographics. Logistic regression assessed 30-day mortality, adjusted for season, patient demographics, and clinical characteristics. Overall and NOAA climate region-stratified relationships were assessed. Results: There were 311,213 unique stroke hospitalizations (mean age 78.8 y, 53% women, 84% White) and 274,703 for AMI (mean age 77.6 y, 45.4% women, 86% White). The national hospitalization rate per 100,000 beneficiary-years was 735 for stroke and 639 for AMI. Thirty-day mortality was 12.0% for stroke and 12.8% for AMI. Each 1 o F increase in daily temperature range was associated with a 1.26 percentage point (95% CI 1.09-1.44) increase in stroke and a 1.48 percentage point (95% CI 1.43-1.53%) increase in AMI hospitalizations and varied by climate region (figure). Daily temperature range had little influence on stroke or AMI mortality (both OR 1.00, 95% CI 1.00-1.00). Conclusions: Daily temperature fluctuations were associated with increased hospitalizations for stroke and AMI. Additional research is needed to understand meteorological effects on vascular events to inform prevention efforts for vulnerable populations.