Could strokes be triggered by changes in the weather?

Researchers from the Yale School of Public Health have discovered a link between cold weather and risk of stroke – the study results showed that cooler temperatures and variation in temperature meant people were more likely to suffer a fatal stroke.

Researchers from the Yale School of Public Health have discovered a link between cold weather and risk of stroke – the study results showed that cooler temperatures and variation in temperature meant people were more likely to suffer a fatal stroke.

Judith Lichtman, Associate Professor of the Epidemiology Department, which carried out the study, said: “Weather is not something people would typically associate with stroke risk, however, we’ve found weather conditions are among the multiple factors that are associated with stroke hospitalisations.”

Surprising results

The study looked at 134,510 people aged 18 and over who had been admitted to hospital between 2009-2010, after an ischemic stroke. This is the most common type of stroke, where a blood clot forms and blocks the flow of blood to the brain. Information gathered was compared with weather data and the results showed that higher than average humidity and significant daily changes in temperature led to higher rates of stroke hospitalisation.

Professor Lichtman commented: “Further 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.”

Although it’s still not understood why winter causes blood pressure to rise, high blood pressure remains the biggest stroke risk factor. Nevertheless, carers of those at risk of strokes should make sure their relative or patient keeps warm this winter.