Study: No Long-Lasting Vioxx Heart Risk
Risk Goes Away When Vioxx Use Stops; Low-Dose Celebrex Seems Safe
Jan. 31, 2005 -- The heart attack risk linked to
goes away after a person stops taking the drug, data from elderly Canadians
"It wasn't enough you took Vioxx three months ago -- you actually had to
be currently exposed to have an increased risk of heart attack," James M.
Brophy, MD, PhD, tells WebMD. "How long after you take Vioxx would you be
considered at risk? More studies are needed to tease that out."
Brophy and colleagues at McGill University in Montreal reviewed medical
records on nearly 114,000 people over the age of 66. They used the data to look
at who did and who did not have a heart attack after beginning NSAID
anti-inflammatory drug) include traditional anti-inflammatory drugs, such as
ibuprofen and naproxen, as well as newer ones, such as and Vioxx. The new
drugs -- known as Cox-2 inhibitors -- got their name because they selectively
block an enzyme called Cox-2.
Brophy's team has more good news. Celebrex -- at low doses -- does not
appear to increase heart attack risk.
"Yes, our study suggests that low-dose Celebrex is safe," Brophy
says. "This is not a randomized study, so it is not proof of safety. But
within the limits of an observational study, our data provides an element of
confidence that Celebrex -- at least in conventional low dose of 200 milligrams
per day -- appears to be very safe."
On the other hand, the study confirms that Vioxx -- even at a low dose --
actually does increase a person's risk of heart attack.
"Our data would tend to support the wisdom of taking Vioxx off the
market," Brophy says. "The data already was rather conclusive from
clinical trials. We add an element of precision, in that we have looked at a
much larger population. ... In our study, 239 patients were taking Vioxx at the
time of their heart attack. So we add a sense of confirmation and precision to
The findings come from elderly people who'd never had a heart attack before
taking an NSAID.
How Safe Is High-Dose Celebrex?
Merck pulled Vioxx off pharmacy shelves when it became clear that the drug
raised the risk of heart attacks. Fearing that other Cox-2 drugs might have
similar -- if less dramatic -- side effects, doctors have been much more
careful in prescribing Celebrex and Bextra. Some groups have
on these drugs until their heart safety can be assured.
Now, in an early release from the April 5, 2005 issue of Annals of
Internal Medicine, Brophy's team provides more information. They found
- Celebrex did not increase heart attack risk.
- Vioxx did indeed increase heart attack risk.
- Taking low-dose Vioxx -- 25 milligrams per day or less -- raised heart
attack risk by 24%.
- Taking high-dose Vioxx -- more than 25 milligrams per day -- increased
heart attack risk by 73%.
- People who took Vioxx in the past, but who stopped taking the drug, did not
have a higher risk of heart attack.
- Taking aspirin along with low-dose Vioxx protected against increased risk
of heart attack, but taking aspirin along with high-dose Vioxx offered no
protection at all.
- Traditional NSAIDs did not increase heart attack risk. A report in December
2004 linked (naproxen) to an
increase in heart attacks and strokes, but this study found no connection.