Stroke mortality up when temperature drops

HealthDay News — Stroke hospitalizations and death rates may rise and fall with changes in the weather, according to researchers at the American Heart Association’s 2014 International Stroke Conference.

Larger daily temperature changes and higher average dew point were associated with higher stroke hospitalization rates, whereas lower average temperatures resulted in more stroke hospitalizations and death, Judith H. Lichtman, PhD, MPH, from the Yale School of Public Health in New Haven, Conn., and colleagues reported at the meeting.

“People at risk for stroke may want to avoid being exposed to significant temperature changes and high dew point and, as always, be prepared to act quickly if they or someone they know experiences stroke signs and symptoms,” Lichtman said in a press release.

The researchers used the Nationwide Inpatient Sample and identified 134,510 adults hospitalized for ischemic stroke from 2009 to 2010 (mean age, 72 years). They then linked the National Climatic Data Center’s temperature and dew point data to stroke discharges at the county level.

For each 1° Fahrenheit increase in average temperature there was an associated 0.86% decrease in the odds of stroke hospitalization and a 1.1% decrease in the odds of dying in-hospital after stroke, the researchers found.

Daily temperature fluctuation and average dew point were associated with increased odds of stroke hospitalization (odds ratio, 1.02 and 1.01, respectively), but not with dying in the hospital. In risk-adjusted analyses, these relationships remained.

“Future research is needed to better understand the cause and effect of changes in weather conditions, as well as to explore potential mechanisms for this association,” Lichtman said.