Heart failure rates are likely to increase over the coming months, according to scientists.
This is because a large-scale Canadian study has found that cold temperatures could trigger the condition in some people.
Researchers are advising elderly people – who are at a higher risk – to avoid fog and low cloud in winter months.
This is because dropping temperatures and changes in atmospheric pressure can cause the heart to react dangerously.
“Our study shows that exposure to cold or high-pressure weather could trigger events leading to hospitalisation or death in heart failure patients,” Pierre Gosselin, one of the researchers from Universitié Laval.
“We know that doctors rarely take the weather forecast into account when treating or making recommendations to heart failure patients.
“So with the extreme differences in temperature due to climate change, we wanted to show how the weather is becoming a more relevant factor.”
In the study, the researchers looked at 112,793 people over the age of 65 who were diagnosed with heart failure.
There was a higher hospitalisation for heart failure between October and April, compared to May and September.
Death or a hospital visit due to heart failure was 0.7 per cent more likely for every 1°C decrease in temperature over the previous week.
Previous research also link cold weather to an increased risk in heart attack.
A Swedish study presented to the European Society of Cardiology last month showed a link between a drop in temperatures and a spike in rates.
The influence of temperature on heart health is thought to be because the body reacts naturally to the cold.
Consequently, the heart is triggered to beat faster to keep us warm, while the body simultaneously tightens its arteries in response to the cold.
This decreases thermal conduction in the skin – which is heat transfer via the skin – which raises blood pressure.
However, the majority of people should not be too worried about winter weather.
“In the majority of healthy people these [cold weather] mechanisms are well tolerated,” said Moman Mohammad from Lund University, one of the researchers in the Swedish study.
“But in people with atherosclerotic plaques in their coronary arteries they may trigger a heart attack.”