Ibruprofen and other commonly used painkillers for treating inflammation may increase the risk of heart attack

Jun 10 2005

Ibruprofen and other commonly used painkillers for treating inflammation may increase the risk of heart attack, researchers from The University of Nottingham say in this week’s BMJ.

Patients should not stop taking the drugs involved - non-steroidal anti-inflammatory drugs (NSAIDS) - but further investigation into these treatments is needed, say the authors.

In the biggest study of its kind to date, researchers identified 9,218 patients aged between 25 and 100 across England, Scotland and Wales who suffered a heart attack for the first time over a four-year period. The data came from the QRESEARCH database, run by the University in collaboration with the IT software provider EMIS. QRESEARCH automatically collects real-time anonymised clinical data from 500 GP practices (representing around 3.5 million patients) throughout the UK.

The researchers, led by Professor Julia Hippisley-Cox in the University’s Division of Primary Care, looked at the prescribing patterns for these patients, tracking whether and when they had been prescribed NSAIDS. NSAIDS are commonly prescribed to relieve inflammation and pain, and include ibruprofen, diclofenac, naxproxen, celecoxib and rofecoxib, as well as a host of other less-commonly prescribed anti-inflammatories.

The findings were adjusted to allow for several other heart attack risk factors - including age, obesity and smoking habits. Importantly, they also adjusted for whether the patient had already suffered from heart disease, or whether they were being prescribed aspirin.

The researchers found that for those prescribed NSAIDS in the three months before the heart attack, the risk increased compared with those who had not taken these drugs in the previous three years. For ibruprofen, the risk increased by almost a quarter (24 per cent) and for diclofenac it rose by more than half (55 per cent).

The newer generation of anti-inflammatories - COX-2 inhibitors - were also associated with increased rates of first-time heart attack. Those prescribed the drugs in the proceeding three months were at 21 per cent higher risk of heart attack if taking celecoxib, and 32 per cent increased risk if taking rofecoxib.

Since this study was concluded rofecoxib has already been withdrawn following concerns over heart attack risk. This is all the more important for the impact of this study on patients, say the authors, since those previously taking rofecoxib will have already turned to the other anti-inflammatories in greater numbers.

The most significant findings were for drugs ibruprofen, diclofenac and rofecoxib, say the authors. In terms of ‘numbers needed to harm’ in the 65 and over age group, for those taking diclofenac, one extra patient for every 521 was likely to suffer a first-time heart attack. For refecoxib the figure was one patient for every 695; and for ibruprofen one patient for every 1005 was at risk.

“Given the high prevalence of the use of these drugs in elderly people and the increased risk of myocardial infarction (heart attack) with age, the relatively large number of patients needed to harm could have considerable implications for public health,” say the authors.

The nature of this report - an observational study - may make it prone to other explanations for the findings, say the authors. “However, enough concern exists to warrant a reconsideration of the cardiovascular safety of all NSAIDS,” they conclude.