Abstract P104: Impact of Cold Weather on Cardiovascular Diseases in Texas

Background: Cardiovascular disease (CVD) has been estimated to account for nearly 50% of total deaths during cold seasons, and cold weather has been shown to have a significant impact on CVD. More importantly, detrimental health effects of cold were particularly pronounced in regions with mild winter climate. Texas is the second largest state in the U.S. and is associated with varying climates. This study aims to improve the understanding of how cold weather affects CVD-related mortality and morbidity in Texas. Methods: We obtained mortality data (1990-2013) and emergency hospital admissions (EHA) data (2003-2014) from the Texas Department of State Health Services and weather data from the National Climate Data Center. Our analysis included cases diagnosed as cardiovascular disease (CVD, ICD-9 390-429; ICD-10 I01-I52), ischemic heart disease (IHD, ICD-9 410-414; ICD-10 I20-I52), myocardial infarction disease (MI, ICD-9 410; ICD-10 I21, I22) and stroke (ICD-9 430-438; ICD-10 I60-I69). We first applied Poisson regression models to 12 Texas major Metropolitan Areas (MSAs) to estimate cold effects on deaths and hospital admissions related to CVDs. A random effects meta-regression analysis was then used to estimate pooled effects for the entire state. Results: With a 1°C decrease in temperature below a MSA-specific threshold, increased death risks were observed in CVDs (1.8% [95%CI: 1.1%, 2.6%]), stroke (1.2% [95%CI: -0.2%, 2.6%]), IHD 2.5% [95%CI: 1.1%, 4.0%], and MI 4.3% [95%CI: 1.2%, 7.5%]). Estimates of cold effects were lower for EHA risks, and they were 1.1% (95%CI: 0.4%, 1.8%) for CVDs, 2.3% (95%CI: -0.3%, 4.9%) for stroke, 1.7% (95%CI: -0.1%, 3.6%) for IHD, and 0.3% (95%CI: -3.5%, 4.2%) for MI. Conclusion: This is the first multi-city study in the U.S. that examined the effect of cold weather on CVD using both mortality and hospital admission data. Cold weather increases mortality risk significantly but less in EHA risk in Texas, and effects vary geographically. Our findings can provide insights to design better intervention strategies for targeted vulnerable populations towards reducing adverse health effects of cold weather.