Safety of Arthritis Drugs
Few people with arthritis would be willing to stop taking a medication that works, especially when nothing else has.
The unsettling news that popular arthritis drugs (specifically the NSAIDs and COX-2 selective inhibitors) could cause a heart attack or stroke or aggravate high blood pressure has left some patients wondering whether they should keep taking them to treat their arthritis.
Health officials say that, as with any drug, only you and your doctor can determine the level of risk that is acceptable with medications currently available to treat arthritis.
Cardiovascular Risk With Arthritis Drugs
Data from clinical trials showed that cyclooxygenase-2 selective agents, better known as COX-2 selective inhibitors, may be associated with an increased risk of serious cardiovascular problems, especially when used in high doses or for long periods in patients with existing cardiovascular disease, or in very high-risk situations, such as immediately after heart surgery. COX-2 selective inhibitors are the newest subset of nonsteroidal anti-inflammatory drugs (NSAIDs).
COX-2 selective inhibitors were developed specifically to decrease the well-recognized gastric side effects and intolerance associated with the use of some NSAIDs.
Traditional NSAIDs, such as aspirin or ibuprofen, act by blocking the production of a family of chemicals known as prostaglandins, which are not only important in the development of inflammation, but also play an important role in maintaining the integrity of the stomach lining. At least two enzymes are involved in this inflammation, namely cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2).
Traditional NSAIDs inhibit both COX-1 and COX-2. Unfortunately, this non-selective inhibition of both COX enzymes also inhibits those prostaglandins involved in some of the important "housekeeping" functions of the body, such as helping blood to clot and protecting the stomach from ulceration.
It's this non-selective inhibition of both enzymes by aspirin and other non-selective NSAIDs that increases the risk of stomach ulcers and consequent bleeding. In theory, the newer COX-2 selective inhibitors only inhibit the enzyme involved in inflammation, leaving the other functions alone.
The downside of the COX-2 selective inhibitors is that they appear to be associated--particularly when used for many consecutive months to years--with an increased risk of cardiovascular problems. Moreover, COX-2 selective inhibitors, like other NSAIDs, don't influence the course of the disease--which doctors say is a common misconception among patients--because these drugs only provide for symptom relief.
Coincidentally, preliminary results from a three-year trial on the non-selective NSAID naproxen (Aleve) also suggested that long-term use may be associated with an increased risk for cardiovascular problems.
FDA Regulatory Actions
Since the results of studies on both non-selective and selective NSAIDs were preliminary and conflicted with data from earlier studies of the same drugs, the FDA issued a public health advisory in December 2004 concerning use of all NSAIDs, pending further review of data that continues to be collected.
From February 16-18, 2005, the FDAs Arthritis and Drug Safety and Risk Management Advisory Committee, met in a joint meeting to discuss the safety of the COX-2 selective inhibitors and traditional NSAIDs. On April 7, 2005, the FDA announced planned regulatory actions for both selective and non-selective NSAIDs.
Many government and private organizations are working together to carry out a plan to guide the use of the nation's resources to decrease the burden of arthritis for all Americans and increase the quality of life of those affected by arthritis. Called the "National Arthritis Action Plan: A Public Health Strategy," it provides a blueprint for:
- relieving arthritis pain
- reducing activity limitations and disability among people with arthritis
- preventing many types of arthritis
As for the safety of future arthritis treatments, experience has shown that the full magnitude of some potential risks of all drugs has not always emerged during the mandatory safety and effectiveness studies conducted before the FDA can approve a drug. As always, the FDA advises physicians to consider the evolving information on any medication in evaluating the risks and benefits of these drugs in individual patients.
Source: Helpful Treatments Keep People With Arthritis Moving; By Carol Rados, FDA Consumer Magazine, March-April 2005 Issue