Diclofenac is having a cardiovascular health risk compared with non-use, paracetamol use, and use of other traditional non-steroidal anti-inflammatory drugs, as per research. The research was conducted by Morten Schmidt and published at the BMJ.
The cardiovascular risks of non-aspirin, non-steroidal anti-inflammatory drugs (NSAIDs) remain a major safety concern after rofecoxib’s thromboembolic properties were revealed. Diclofenac is a traditional NSAID with cyclo-oxygenase-2 (COX 2) selectivity similar to COX 2 inhibitors,2 but its cardiovascular risks compared with those of other traditional NSAIDs have never been examined in a randomised controlled trial.
Diclofenac is the most frequently used NSAID in low, middle, and high income countries, and is available over the counter in most countries;5 therefore, its cardiovascular risk profile is of major clinical and public health importance.
Individuals eligible for inclusion were all adults without malignancy; schizophrenia; dementia; or cardiovascular, kidney, liver, or ulcer diseases (that is, with low baseline risk). The study included 1 370 832 diclofenac initiators, 3 878 454 ibuprofen initiators, 291 490 naproxen initiators, 764 781 healthcare seeking paracetamol initiators matched by propensity score, and 1 303 209 healthcare seeking non-initiators also matched by propensity score.
As per result of the trial, the adverse event rate among diclofenac initiators increased by 50% compared with non-initiators, 20% compared with paracetamol or ibuprofen initiators, and 30% compared with naproxen initiators. The event rate for diclofenac initiators increased for each component of the combined endpoint for atrial fibrillation/flutter, ischaemic stroke, heart failure, myocardial infarction, and cardiac death as well as for low doses of diclofenac, compared with non-initiators.
Although the relative risk of major adverse cardiovascular events was highest in individuals with low or moderate baseline risk (that is, diabetes mellitus), the absolute risk was highest in individuals with high baseline risk (that is, previous myocardial infarction or heart failure). Diclofenac initiation also increased the risk of upper gastrointestinal bleeding at 30 days, by approximately 4.5-fold compared with no initiation, 2.5-fold compared with initiation of ibuprofen or paracetamol, and to a similar extent as naproxen initiation.
