Abstract T P133: Hot and Humid in Alabama: Atmospheric Parameters and Stroke Admissions

Abstract

Background&Purpose: evidence is conflicting on the effects of atmospheric conditions on the incidence of acute ischemic stroke (AIS). Since acute stroke patients are often brought to hospitals in clusters, we sought to examine the correlation of local weather parameters with AIS admission rates in a region of the United States affected by wide fluctuations in temperature and humidity. Subjects&Methods: Basic patient demographics, stroke severity and admission dates were collected from our prospectively collected registry of consecutive acute ischemic strokes at our tertiary center. Atmospheric temperature (°F) and humidity (%) levels were obtained for each month for 3 consecutive years (2010-2012) using http://weatherspark.com/averages publicly available data. Results: A total of 2014 consecutive AIS patients were admitted (47% women, mean age 63±15 years, median NIHSS 5, IQR 8). Ischemic stroke admissions increased linearly with both minimum (r=0.52; p=0.001) and maximum (r=0.51; p=0.001) temperature increases. Maximum humidity levels were negatively correlated with AIS admissions throughout the year (r= - 0.39; p=0.010) while minimum humidity levels yield opposite correlation with IS admissions (r=0.43; p=0.007). There was no effect of age, gender or race on these correlations. When the different seasons were evaluated separately, the strongest correlation between lower humidity levels and IS admissions was noted during summer (r=0.474; p=0.197), while higher humidity levels appeared to correlate more strongly with hospital admissions during autumn (r= - 0.596; p=0.090). Conclusions: our study showed that humidity levels and temperature rises may affect the number of acute ischemic stroke admissions in a humid subtropical climate. Non-random clustering of IS admissions during the year underscores a potential role for atmopsheric parameters in determining allocaton of resources to treat stroke.