Are anti-inflammatory drugs like naproxen bad for your heart?

According to new research, widely used painkillers are being wrongly prescribed to people with heart conditions, which could cause them to have worsening symptoms and even strokes. 

The study suggests people with heart failure and those taking blood thinners to prevent blood clots are losing years of good health after taking non-steroidal anti-inflammatory drugs (NSAIDs). 

These medicines are used to treat pain and inflammation.  

The study included people on four types of NSAIDs: naproxen, ibuprofen, diclofenac sodium and celecoxib. 

Guidance from the National Institute for Health and Care Excellence (NICE) already says people with severe heart failure should not be prescribed NSAIDs. 

NICE also says they should be prescribed with caution to people who; have heart failure, take blood thinners to prevent blood clots (anticoagulants), have long-term kidney disease, have had a stomach (peptic) ulcer, are aged over 65.  

But this new study, published in the British Medical Journal (BMJ), suggests that some people who fit these criteria are still being prescribed NSAIDs, which are also known to cause gut problems such as bleeding.

The research, which used data from nearly 11 million people in England from April 2020, looked at how many people with heart failure were being prescribed an NSAID as a pill.

The UK researchers then estimated how many of these would have worsening heart failure symptoms because of the NSAID over 10 years.

They predicted this would result in 6,700 extra episodes of heart failure symptoms getting worse than if NSAIDs had not been prescribed to this group.

Overall, 28,061 people experienced a serious side effect from the drugs

They also estimated that among those taking an NSAID and an anticoagulant such as warfarin or a direct oral anticoagulant (DOAC) there would be an extra 2,000 strokes over 10 years.

As well as looking at people with heart failure and those on anticoagulants, the researchers examined the effects of NSAIDs on people in three other groups: those with long-term kidney disease, those who had had a peptic ulcer, and anyone over 65 who was taking an NSAID without another medicine to protect their gut.

Overall, 28,061 people across these five groups experienced a serious side effect from the drugs.

The researchers then went on to predict that these people would be linked to 778 excess deaths in England in the next 10 years.

What did the researchers say?

The idea that NSAIDs can lead to harmful side effects in some people is not new.

In their study, the researchers cite research that says they are responsible for 30 per cent of hospital admissions related to adverse drug events – mainly due to bleeding in the gut, heart attack, stroke and kidney problems. 

The findings come from a 2004 study that included aspirin as an NSAID – another drug that is also used at low doses to help stop blood clotting.  

However, without aspirin being included, NSAIDs were behind just 11.8 per cent of admissions for adverse drug events, the study shows. 

Newer research also suggests that the number of adverse events with NSAIDs is much lower.  

A study published in 2022 in BMJ Open found only 0.85% of 218 adverse drug events over a month were caused by NSAIDs, not including aspirin. 

This lower level of adverse events is likely because of NHS action over the last 25 years to prevent “problematic prescribing” of NSAIDs, the researchers say, adding that prescriptions of these medicines fell by 12 per cent between 2017 and 2022 in England. 

But this study suggests that they continue to cause harm in some patients. 

The team used an economic model to estimate that prescribing NSAIDs to high-risk groups would cost the NHS in England £31 million over 10 years.

How good was the research?

The study used a large pool of data from 10,906,453 people registered to GP practices in England.

While the research suggested the effects of high-risk people being prescribed NSAIDs could add up over 10 years across the entire population, the number of people affected by serious side effects was still very small. 

Only eight people with heart failure per 1000 (87,804 out of 11 million) were being prescribed an NSAID. And less than one per 1000 experienced worsening heart failure symptoms as a result.

Among those taking anticoagulants, just 22 out of 1000 (245,778) were given an NSAID, and less than one in 1000 died, had a stroke or experienced gut problems such as a bleed or an ulcer.

The number of people affected by serious side effects was still very small

The researchers also admitted their model had to assume that all those taking an NSAID were taking a consistent dose of one type called naproxen for 10 years.

However, earlier research published in BMJ Open in 2023 of people on NSAIDs, shows only around two thirds of people are prescribed them for more than two months.

And even people living with long-term pain may have changed their dose over this time as their condition got better or worse.

The NHS data used in the study also shows that only around two-thirds of the NSAID prescriptions issued in 2022 were for naproxen, with nearly a third of people taking a different type of NSAID. 

How good was the media coverage?

Lots of UK news outlets reported on the study, including the Daily Express, The Independent, Daily Mail and The Sun.

But none of them made it clear that the number of high-risk people prescribed NSAIDs and affected by these serious side effects was very small, at less than one in 1000.

And only the Daily Express and The Independent mentioned that many people could still use the drugs safely.

Many of the headlines did not reflect the fact that we already know about the increased risk of certain side effects, including heart attack and strokes in some people, from NSAIDs.

For example, some people reading the headline in the Daily Express; “Cheap pill almost everyone takes could cause heart attack and stroke”, could believe that these were new research findings.

Also, the study did not include data on heart attacks, and only predicted an increase in strokes over 10 years among those who are also taking a blood thinner (anticoagulant).

The BHF verdict

We already know that NSAIDs can increase the risk of heart and gut problems for certain groups of people, including those with heart conditions such as heart failure.

However, the risk of serious side effects is very low and heart-related complications are rare, especially if you’re under 65, do not have these conditions and only take these drugs occasionally.

If you do have heart, kidney or gut problems, you’re over 65 or you’re taking medicine to prevent blood clots, make sure to speak to your doctor, as NSAIDs should be used with caution.

This may include taking lower doses for the shortest possible time, taking medicines that protect your gut as well, or avoiding them altogether.

What to read next...