CHICAGO (AP) _ Three new studies are adding to a raging debate over whether the popular arthritis pain reliever Vioxx increases the risk of heart attack.
The editor of the Archives of Internal Medicine, which published the studies in its May 27 edition, says the results offer reassuring evidence that drugs like Vioxx and Celebrex are not bad for the heart.
But a cardiologist and a co-author of one of the studies said the safety issue is not resolved.
The new studies involved the older arthritis painkiller naproxen, not the newer class of pain relievers to which Vioxx and Celebrex belong. Vioxx maker Merck & Co. conducted or funded two of the three studies.
According to the Archives report, the studies all found that patients taking naproxen had a lower heart attack risk than those who did not use the drug.
One of the studies, involving 4,425 heart attack patients and 17,700 others, linked naproxen use to a 16 percent to 20 percent reduction in heart attack risk.
Vioxx maker Merck has argued its product is not bad for the heart, and that naproxen's apparent heart-protective benefits are the result of thinning the blood.
The three studies ``support what Merck scientists have been saying,'' said Dr. Alise Reicin, Merck's head of clinical research.
Archives editor Dr. James E. Dalen also called the studies ``good news for the millions of users of cox-2 inhibitors.''
Vioxx and Celebrex both belong to the group of drugs, called cox-2 inhibitors, that work by blocking the action of an enzyme involved in the inflammation process.
But cardiologist Dr. Eric Topol of the Cleveland Clinic said the Food and Drug Administration's order last month for new precautions on Vioxx's label is still warranted.
Topol took part in an analysis last year of data that showed Vioxx users faced double the risk of serious cardiovascular problems, including stroke and heart attack. He said the newest research leaves the question ``far from settled.''
Dr. Daniel Solomon of Harvard's Brigham and Women's Hospital, co-author of one of the Archives studies, agreed.
``None of the studies contain a patient who is on a cox-2 agent, so it's impossible really to comment on the safety'' of drugs like Vioxx, Solomon said.
Solomon said naproxen users might have other traits or health habits that would explain the findings. Solomon's study was not funded by a pharmaceutical company.