Use of Non-Steroidal Anti-Inflammatory Drugs That Elevate Cardiovascular Risk: An Examination of Sales and Essential Medicines Lists in Low-, Middle-, and High-Income Countries

Patricia McGettigan and David Henry find that, although some non-steroidal anti-inflammatory drugs (NSAIDs) such as diclofenac are known to increase cardiovascular risk, diclofenac is included on 74 countries' essential medicine lists and was the most commonly used NSAID in the 15 countries they evaluated. Background: Certain non-steroidal anti-inflammatory drugs (NSAIDs) (e.g., rofecoxib [Vioxx]) increase the risk of heart attack and stroke and should be avoided in patients at high risk of cardiovascular events. Rates of cardiovascular disease are high and rising in many low- and middle-income countries. We studied the extent to which evidence on cardiovascular risk with NSAIDs has translated into guidance and sales in 15 countries. Methods and Findings: Data on the relative risk (RR) of cardiovascular events with individual NSAIDs were derived from meta-analyses of randomised trials and controlled observational studies. Listing of individual NSAIDs on Essential Medicines Lists (EMLs) was obtained from the World Health Organization. NSAID sales or prescription data for 15 low-, middle-, and high-income countries were obtained from Intercontinental Medical Statistics Health (IMS Health) or national prescription pricing audit (in the case of England and Canada). Three drugs (rofecoxib, diclofenac, etoricoxib) ranked consistently highest in terms of cardiovascular risk compared with nonuse. Naproxen was associated with a low risk. Diclofenac was listed on 74 national EMLs, naproxen on just 27. Rofecoxib use was not documented in any country. Diclofenac and etoricoxib accounted for one-third of total NSAID usage across the 15 countries (median 33.2%, range 14.7–58.7%). This proportion did not vary between low- and high-income countries. Diclofenac was by far the most commonly used NSAID, with a market share close to that of the next three most popular drugs combined. Naproxen had an average market share of less than 10%. Conclusions: Listing of NSAIDs on national EMLs should take account of cardiovascular risk, with preference given to low risk drugs. Diclofenac has a risk very similar to rofecoxib, which was withdrawn from worldwide markets owing to cardiovascular toxicity. Diclofenac should be removed from EMLs. Background: Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used drugs. Aspirin, the first NSAID, was developed in 1897 but there are now many different NSAIDs. Some can be bought over-the-counter but others are available only with prescription. NSAIDs can help relieve short- and long-term pain, reduce inflammation (redness and swelling), and reduce high fevers. Common conditions that are treated with NSAIDs include headaches, toothache, back ache, and arthritis. NSAIDs work by stopping a class of enzymes called cyclo-oxygenases (COXs) from making prostaglandins, some of which cause pain and inflammation. Like all drugs, NSAIDs have some unwanted side effects. Because certain prostaglandins protect the stomach lining from the stomach acid that helps to digest food, NSAID use can cause indigestion and stomach ulcers (gastrointestinal complications). In addition, NSAIDs increase the risk of heart attacks and stroke to varying degrees and therefore should be avoided by people at high risk of cardiovascular diseases—conditions that affect the heart and/or blood vessels. Why Was This Study Done?: Different NSAIDs are associated with different levels of cardiovascular risk. Selective COX-2 inhibitors (e.g., rofecoxib, celecoxib, etoricoxib) generally have fewer stomach-related side effects than non-selective COX inhibitors (e.g., naproxen, ibuprofen, diclofenac). However, some NSAIDs (rofecoxib, diclofenac, etoricoxib) are more likely to cause cardiovascular events than others (e.g., naproxen). When doctors prescribe NSAIDs, they need to consider the patient's risk profile. Particularly for patients with higher risk of cardiovascular events, a doctor should either advise against NSAID use or recommend one that has a relatively low cardiovascular risk. Information on the cardiovascular risk associated with different NSAIDs has been available for several years, but have doctors changed their prescribing of NSAIDs based on the information? This question is of particular concern in low- and middle-income countries where cardiovascular disease is increasingly common. In this study, the researchers investigate the extent to which evidence on the cardiovascular risk associated with different NSAIDs has translated into guidance and sales in 15 low-, middle-, and high-income countries. What Did the Researchers Do and Find?: The researchers derived data on the relative risk of cardiovascular events associated with individual NSAIDs compared to non-use of NSAIDs from published meta-analyses of randomized trials and observational studies. They obtained information on the NSAIDs recommended in 100 countries from national Essential Medicines Lists (EMLs; essential medicines are drugs that satisfy the priority health care needs of a population). Finally, they obtained information on NSAID sales for 13 countries in the South Asian, Southeast Asian, and Asian Pacific regions and NSAID prescription data for Canada and England. Rofecoxib, diclofenac, and etoricoxib consistently increased cardiovascular risk compared with no NSAIDs. All three had a higher relative risk of cardiovascular events than naproxen in pairwise analyses. Naproxen was associated with the lowest cardiovascular risk. No national EMLs recommended rofecoxib, which was withdrawn from world markets 8 years ago because of its cardiovascular risk. Seventy-four national EMLs listed diclofenac, but only 27 EMLs listed naproxen. Diclofenac was the most commonly used NSAID, with an average market share across the 15 countries of nearly 30%. By contrast, naproxen had an average market share of less than 10%. Finally, across both high- and low-/middle-income countries, diclofenac and etoricoxib accounted for one-third of total NSAID usage. What Do These Findings Mean?: These findings show that NSAIDs with higher risk of cardiovascular events are widely used in low-/middle- as well as high-income countries. Diclofenac is the most popular NSAID, despite its higher relative risk of cardiovascular events, which is similar to that of rofecoxib. Diclofenac is also widely listed on EMLs even though information on its higher cardiovascular risk has been available since 2006. In contrast, naproxen, one of the safest in relative terms of the NSAIDs examined, was among the least popular and was listed on a minority of EMLs. Some aspects of the study's design may affect the accuracy of these findings. For example, the researchers did not look at the risk profiles of the patients actually taking NSAIDs. However, given the volume of use of high-risk NSAIDS, it is likely that these drugs are taken by many individuals at high risk of cardiovascular events. Overall, these findings have important implications for public health and, given the wide availability of safer alternatives, the researchers suggest that diclofenac should be removed from national EMLs and that its marketing authorizations should be revoked globally. Additional Information: Please access these Web sites via the online version of this summary at http://dx.doi.org/ 10.1371/journal.pmed.1001388.