Widely used pain relievers may increase the risk of cardiac infarction when used during a cold or flu-like illness, according to a new study.
The findings, published in the Journal of Infectious Diseases, suggest clinicians should use caution when prescribing non-steroidal anti-inflammatory drugs to ease symptoms of acute respiratory infections, according to researchers.
“NSAIDs during an acute respiratory infection might further increase the risk of a heart attack”
In an observational study, the researchers from Taiwan looked at data on nearly 10,000 patients who were admitted to hospital for a heart attack during 2005-11.
They investigated whether two potential cardiac risk factors – an acute respiratory infection, such as a cold or influenza, and NSAID use – had a combined, joint effect on heart attack risk.
The researchers compared each patients’ own risk for heart attack over time, across episodes of respiratory illness and NSAID use. They found a stronger association with a heart attack when both risk factors were present.
Using NSAIDs during an acute respiratory infection was associated with a 3.4-fold increased risk for a heart attack, with 7.2 times greater risk when patients received the pain-relieving medication intravenously in the hospital, compared to times when patients had neither of the risk factors.
The heart attack risk when patients with an acute respiratory illness were not taking an NSAID was 2.7 times greater, while the risk was 1.5 times greater when individuals took the drugs and did not have an infection.
“Clinicians should consider both medical conditions and existing medications when prescribing NSAIDs”
Previous research has implicated respiratory infections and some NSAIDs as potential triggers for heart problems, but earlier studies have examined these risk factors only separately.
Study author Dr Cheng-Chung Fang, from the National Taiwan University Hospital, said clinicians “should be aware that the use of NSAIDs during an acute respiratory infection might further increase the risk of a heart attack”.
While the new findings suggest an association between NSAID use, acute respiratory infections, and increased cardiac risk, they do not prove a cause-and-effect relationship, admitted the researchers.
Additional research is needed to clarify the apparent combined effect on risk and how the effect might be managed, they highlighted.
Future studies could explore whether specific NSAIDs may be safer than others for patients with such infections, how illness severity affected the risks, and whether those who have previously had heart attack may be more susceptible, said the authors.
In a related editorial in the same journal, public health experts from the UK and Canada said the findings provided evidence for the dual effect of potential heart attack triggers and highlighted a need for caution when using NSAIDs while more studies explored the issue.
“Clinicians should consider both medical conditions and existing medications when prescribing NSAIDs for symptomatic acute respiratory infection relief,” said Dr Charlotte Warren-Gash, from the London School of Hygiene and Tropical Medicine, and Dr Jacob Udell, from the University of Toronto.