MedicalResearch.com Interview with:
Anne-Marie Schjerning Olsen, MD, PhD
Department of Cardiology
Gentofte Hospital, University of Copenhagen
MedicalResearch.com: What is the background for this study?
Dr. Olsen: The question addressed in the study was: Do people who have had a myocardial infarction (heart attack) and are who taking drugs (known as antithrombotics) to reduce their risk of further heart attacks have an increased risk of serious bleeding, especially gastrointestinal bleeding, and of further heart attacks if they also take painkillers known as non-steroidal anti-inflammatory drugs (NSAIDs)?
We found that taking NSAIDs, even for periods of under one week (3-4 days for bleeding), was associated with increased risks of both bleeding and of further heart attacks.
Background: People who have suffered a heart attack are prescribed medicines afterwards to reduce their risk of another one. The medicines usually include two ’antithrombotic drugs’ which make platelets in the blood less sticky – the two most commonly used drugs are aspirin and clopidogrel. A side effect of antithrombotic treatment is that the drugs increase bleeding risk.
Non-steroidal anti-inflammatory drugs (NSAIDs) are used to treat pain and inflammation. They are very effective and are among the most widely used drugs in the world. Some NSAIDs can be bought across the counter without a prescription, for example, ibuprofen. NSAIDs have side effects too. All of them increase the risk of bleeding, especially gastro-intestinal bleeding arising from damage (ulcers) caused to the gut lining. Some NSAIDs, for example diclofenac, are also associated with a small increase in the risk of heart attack – this risk matters most for people already at risk of a heart attack. The medical advice is for these patients to avoid NSAIDs and for their doctors to avoid prescribing them if possible.
But pain is a common problem and very distressing for people – so in practice, NSAIDs are used quite often by patients who have had a heart attack. If NSAIDs are to be taken by heart attack patients, then it is important that both they and their doctors know the risks so that they can weigh up the benefits and downsides and make an informed decision.
What this study did: This was a cohort study that included everyone in Denmark aged 30 years or older who had had a first heart attack and who was taking antithrombotic medicines. Using hospital and dispensing registries, we examined patients who had suffered serious bleeding (causing admission to hospital and/or death) or who had another heart attack or cardiac event to see if they had been prescribed NSAIDs or not.
Dr. Olsen: The study findings: In this study of over 60,000 patients in Denmark taking antithrombotic medicines, one third of them had at least one prescription for NSAIDs, commonly ibuprofen or diclofenac, dispensed over a median study time of 3.5 years. In the same period, 8.5% (5,288 patients or 1 in 12 of the study group) had a gastrointestinal bleed (of whom 799 or 15% died) and 30% (18,568; 1 in 3) had a new cardiac event, mostly heart attack. While these events happened to patients who were prescribed NSAIDs and also to patients were not prescribed NSAIDs, we found that the risk of bleeding was doubled when patients were taking NSAIDs compared with not taking them. The risk occurred within 3 days of starting a NSAID. The risk of a cardiac event (mainly heart attack) was increased by 40% when taking NSAIDs compared with not taking them and also occurred within days of starting a NSAID.
In other words, the NSAIDs appeared 1) to increase the bleeding risk already existing with antithrombotics and 2) to diminish the cardiac protection that antithrombotics provided.
Limitations: This is just one study, although it is a big one. It was a ’real-life’ observational study not a randomised controlled clinical trial. More studies are needed to confirm what we have found.
MedicalResearch: Why is this important information for patients and doctors to know?
Dr. Olsen: NSAIDs were used a lot by the patients in this study – pain is a common problem and can cause great suffering. There has been a tendency to think that short-term use of NSAIDs is safe – our study suggests this in not the case and that even a few days of use is associated with increased risks of both bleeding and cardiac events, mainly heart attacks. People may be happy to take these risks to have relief from pain but it is very important that they aware of the risks and can make an informed decision about taking NSAIDs for pain relief.
Schjerning Olsen A, Gislason GH, McGettigan P, et al. Association of NSAID Use With Risk of Bleeding and Cardiovascular Events in Patients Receiving Antithrombotic Therapy After Myocardial Infarction. JAMA. 2015;313(8):805-814. doi:10.1001/jama.2015.0809.
Anne-Marie Schjerning Olsen, MD, PhD Department of Cardiology (2015). NSAIDS After Heart Attack Increase Risk of Bleeding and Further Heart Attacks