Health education 02: Risk of Painkillers(Diclofenac) on the heart

Painkillers are one of the most widely used medicines worldwide. Although most of them are not OTC(Over the counter) drugs, we have made them OTC. People are getting a good variety of painkillers without a doctor's prescription from their nearby pharmacy. And most of the cases, this doesn't create any health problem. But recent studies show that all painkillers are not as safe as we thought. Besides some minor side effects, a few painkillers may impose a threat on the heart.

Before going to the actual topic, we will have a quick view on different types of painkillers[1]. Broadly, painkillers(another term is analgesics) can be divided into two categories:

Both types of painkillers have some side effects. Addiction, dependency, tolerances etc are important side effects of opioid painkillers which, in most of the countries, patients can't get without a doctors prescription(controlled medicine). But NSAID is readily available and widely used painkillers. Every year 30 millions of people in the USA use NSAID to get rid of pain, fever and headache(According to the National Institute of Health-NIH). At the same time, these NSAID creates some problem like NSAID-induced ulcers in the stomach and duodenum, dyspepsia, exacerbation of bronchial asthma, kidney problem (interstitial nephritis) etc. They have some adverse effects on the heart as well. An extensive review[2] of the existing researches has been done by The European Society of Cardiology. They have concluded:

Non-aspirin NSAIDs should not be prescribed to individuals at high risk of heart disease, nor should they be sold over the counter(OTC) without issuing an "appropriate warning of their frequent cardiovascular complications."

In the remaining post, we will learn about a recent study[3] which was conducted focusing on Diclofenac only, one of the widely used NSAID. It shows evidence in support of previous researches/studies i.e. it carries a risk for the cardiovascular system.

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Risk of Diclofenac on the heart and the Cardiovascular system

Topics	Details
Study conductors	Morten Schmidt[4] and his team
Study type	Observational
Study materials	252 national studies of Denmark
Study population	6.3 million Danish people, aged 46–56
Study Period	20 years (1996-2016)
Study objective	To investigate the cardiovascular risks of taking Diclofenac
Other NSAID compared with	Paracetamol, Ibuprofen, Naproxen
Study findings	* Within 30 days of starting Diclofenac, the rate of major cardiovascular problems(arrhythmia, heart attack, heart failure) was much higher than other NSAID. * The risk of adverse cardiovascular events was 50% higher in Diclofenac takers in comparison with them who didn't take any NSAID. * The risk was 20% higher in them who took diclofenac instead of paracetamol or Ibuprofen. * When the patients started taking diclofenac, the risk of heart problem was higher. But who were continuing the drug, over time, the risk of actual development of heart problems was much higher

Additional findings:

After initiation of Diclofenac, the risk of upper gastrointestinal bleeding was 4.5 times higher than patients who didn't take diclofenac and 2.5 times higher than patients who used ibuprofen or paracetamol.

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This observational study reveals the comparison between the use of diclofenac, no use of any painkillers, use of paracetamol or other NSAID. The author explained,

"Diclofenac poses a cardiovascular health risk compared with non-use, paracetamol use, and use of other traditional nonsteroidal anti-inflammatory drugs,"

One drawback of this study is that it is an observational study. No conclusion about the actual casualty can be made from such a study. But due to the large sample size and quality of the study, clinicians can confidently use this evidence to make a decision regarding prescribing diclofenac.

NSAID is an excellent option in pain as well as in inflammation. Potential side effects are the hinders of using it. As other NSAID are available in the market with fewer side effects, diclofenac use should be minimized. The author said,

"Considering its cardiovascular and gastrointestinal risks, however, there is little justification to initiate diclofenac treatment before other traditional NSAIDs."

Conclusion:
If the intensity of the pain is severe, diclofenac is one of the best options among painkillers. But before prescribing it, a doctor has to take proper history, examine the patient and take decision considering risk-benefits ratio. If the risks are high and alternative painkillers are available, a diclofenac shouldn’t be prescribed. In other conditions, diclofenac is a very good option!

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Reference:

1. Davidson's Principle and Practice of Medicine, Edition 23; page: 1002 and 1345
2. https://academic.oup.com/eurheartj/article/37/13/1015/2398407#86351274
3. https://www.bmj.com/content/362/bmj.k3426
4. Morten Schmidt

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