Cox-2 Drugs Boost Blood Pressure: Study
MONDAY, Feb. 14, 2005 (HealthDay News) -- As a U.S. advisory panel prepares to discuss the future of cox-2 drugs later this week, a new round of studies debating the cardiovascular risks of this class of medication has just surfaced.
One study found that cox-2s raise blood pressure more than traditional nonsteroidal anti-inflammatory inhibitors (NSAIDs) or a placebo. The research, by Australian scientists, appears in the March 15 issue of Archives of Internal Medicine, which was released online Monday.
The finding, said Dr. Kevin Stone, an orthopedic surgeon at the Stone Clinic in San Francisco, is "another nail in the coffin" of cox-2s, which include Celebrex, Bextra and the now-withdrawn Vioxx.
"It jibes with many other things we know," added Dr. Richard Re, head of the hypertension section at the Ochsner Clinic Foundation in New Orleans. "People have had suspicions that this is the case, and this study more or less confirms it."
Another new study, also released Monday, found that Vioxx and Celebrex increased patients' risk of heart attack and stroke by about 20 percent, while Bextra increased the risk by 50 percent. The study was carried out by Indianapolis-based WellPoint Inc., the nation's largest provider of health benefits, according to the Associated Press. And it was done ahead of Vioxx' removal last September.
Dr. Sam Nussbaum, WellPoint's executive vice president and chief medical officer, said Monday that the study is further evidence of an "increasingly compelling trend" of data that show such drugs elevate patients' risk of heart attack and stroke.
A third study, involving laboratory research by scientists at Johns Hopkins University in Baltimore, found more of a middle ground: Properties of the cox-1 and cox-2 enzymes can both protect and damage the brain. The authors state this may help explain why some NSAIDs can relieve pain even while they have other detrimental effects in the body. The findings appear in the February issue of the Journal of Neurochemistry.
Traditional NSAIDs such as aspirin and ibuprofen are used to relieve pain, but are associated with an increased risk of gastrointestinal problems such as bleeding ulcers. The newer cox-2 inhibitor NSAIDs were hailed as wonder drugs when they were introduced in the late 1990s because they relieved pain without the side effects.
Recently, cox-2 inhibitors have been linked to an increased risk of cardiovascular problems. Vioxx was pulled from the market by its manufacturer, Merck & Co., after a study showed that long-term use increased the risk of heart attack and stroke. Celebrex and Bextra, made by Pfizer, are still available to consumers.
For the Australian study, its authors analyzed results from all 19 randomized controlled trials of cox-2 inhibitors that were published before May 2004. Blood pressure information was available for 45,451 participants.
Compared with traditional NSAIDs and with placebos, people taking cox-2 inhibitors had higher blood pressure levels, the researchers found. Participants taking cox-2s had a 60 percent higher chance of elevated blood pressure compared with a placebo, and a 25 percent higher chance compared with the older NSAIDs.
Although these increases were statistically "nonsignificant" when looked at individually, Dr. Henry Krum, senior author of the study, said he felt the changes were clinically significant or "highly relevant when applied to a population."
There were few differences between the different cox-2 drugs, although Vioxx may have been associated with a higher risk compared with Celebrex, he added.
According to Krum, who is director of the NHMRC Center of Clinical Research Excellence in Therapeutics at Monash University/Alfred Hospital in Melbourne, Australia, the study is "not the final word but certainly a potential contributor." Studies looking specifically at cardiovascular outcomes now need to be performed, he added.
Dr. Mark Fendrick, professor of internal medicine at the University of Michigan School of Medicine, felt that a more important message may have receded in the flurry of what he called often-confusing scientific articles on cox-2 drugs.
"What's being lost is, what the heck should patients and doctors be doing and what are the questions they should be asking as all this conflicting information keeps coming through all these venues," he said.
And what should patients be doing? If you can, use non-NSAID therapies, Fendrick said. Consider a cox-2 inhibitor if you are at risk for any type of stomach injury or if you are at low risk for cardiac problems and are not taking aspirin.
If you are at cardiac risk or taking aspirin, consider a "traditional NSAID with a gastrointestinal protective agent," he added.
Stone sees a "seismic shift" happening, with physicians moving to prescribe natural anti-inflammatories such as glucosamine.
"Unfortunately, marketing got way ahead of the science and most likely -- whether or not the FDA forces a recall -- most physicians will step back quite a bit" from cox-2s, Stone said.
Starting Wednesday, an FDA advisory panel will meet for three days to debate the safety and future of the cox-2 drugs.
More information
Read more about the advisory panel meeting at the FDA.
