Heart attacks are more likely to kill people during the winter than in the summer, according to a study.
Cardiologists at Leeds General Infirmary in the UK compared information from 4,056 people who received treatment for a heart attack in four separate years.
They found the most severe heart attacks were more deadly in the coldest six months, compared to the warmest.
The overall number of heart attacks was roughly the same in the coldest half of the year, compared to the warmer months (52 per cent between November and April), with the most serious heart attacks leading to cardiac arrest and cardiogenic shock.
The risk of dying within 30 days of a severe heart attack was nearly 50 per cent higher in the six coldest months, compared to the six warmest months, researchers said.
"There is no physical reason why a heart attack, even the most severe, should be more deadly in winter than in summer so we must do further research to find the cause of this difference and remedy it," said Arvin Krishnamurthy, who led the research.
"Potential explanations could include longer time to treatment, prolonged hospitalisation and delays to discharge, and increased prevalence of winter-associated infections, which in the sickest patients, could be potentially lethal," Krishnamurthy said.
Cardiac arrest occurs when the heart suddenly stops pumping blood around the body, while cardiogenic shock is when the heart can not pump enough blood to meet the body's needs.
Both conditions are often caused by a severe heart attack, but not everyone who has a heart attack has a cardiac arrest or cardiogenic shock.
"You obviously can't choose when you have a major heart attack, but it shouldn't have such an impact on your chances of surviving," said Metin Avkiran, Associate Medical Director at the British Heart Foundation.
"It's vital we carry out more research to find out why there are these differences, as well as continuing to do all we can to stop people having heart attacks in the first place," said Avkiran.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)