“Our research has shown that influenza epidemics are associated with a rise in coronary deaths. This calls for more intensive efforts to increase the vaccination rate in people at risk of coronary heart disease,” said Professor Mohammad Madjid, assistant professor of medicine at the University of Texas-Houston. “Between 10 and 20% of people catch flu every year, and I have estimated that we can prevent up to 90,000 coronary deaths a year in the USA if every high risk patient received an annual flu vaccination.”
Madjid investigate deaths between 1993 and 2000 in St Petersburg that had been shown by autopsy reports to be due to coronary heart disease. “This was a population where only a small minority were receiving flu vaccines or statin drugs, so this enabled us to see what happened naturally in the absence of these medicines,” said Prof Madjid.
They found that 11,892 people died from acute myocardial infarction (AMI) (47.8% men and 52.2% women), and 23,000 died from chronic ischaemic heart disease (IHD) (40.1% men and 59.9% women). The peaks in deaths from both AMI and IHD coincided with the times when influenza epidemics and acute respiratory disease (ARD), which often accompanies flu, were at their height.
They found that the chances of dying from AMI increased by a third in epidemic weeks, compared to non-epidemic weeks, and the chances of dying from IHD increased by a tenth. This was the same for both men and women and in different age groups. The researchers believe that flu causes an acute and severe inflammation in the body, which, in some patients, can destabilise atherosclerotic plaques in coronary arteries and cause heart attacks.
“This study shows that flu is an important trigger of heart attacks because flu is a severe infection, with high incidence rates and is readily preventable. Therefore, our results give us a new tool for preventing heart attacks”, he said.
MEDICA.de; Source: European Heart Journal