Study coauthor Eric Matteson, a Mayo Clinic rheumatologist, stressed that the chances of developing cancer while using these drugs were still small. The researchers also said the medications' benefits included improving flexibility and range of movement, easing pain, and increasing life expectancy, which arthritis can shorten.
Patients' varied risks
In addition, they said risks for individual patients probably varied widely. Older, sicker people who have taken the drugs for several years probably face the highest risks, they said.
Still, the researchers said patients should be made aware of the dangers and told to seek medical help if they develop fevers, coughs, or other symptoms of infection. They should also be sure to undergo the cancer screenings recommended for the general public.
The study appears in today's Journal of the American Medical Association.
More than two million
Matteson is working with Centocor to develop a drug that works similarly, and he and coauthor Tim Bongartz have been paid consultants to Abbott for unrelated work. Neither company funded the study. The Mayo Foundation sponsored the research.
Rheumatoid arthritis affects more than two million Americans. A malfunctioning immune system attacks joints throughout the body, causing pain, deformities and disability.
Dr. John Klippel, president of the Arthritis Foundation, said the study would probably not change doctors' minds, because scores of patients had benefited from the drugs. Remicade was approved in 1998, Humira in 2002.
Matteson's ties to Centocor and his work on a similar medication, Enbrel, were among several omissions and errors included in disclosure statements that accompanied the study in JAMA.
He said that the omissions were "errors of oversight on my part" and that he was not trying to conceal anything.
But in an unusual move, journal editors posted a correction yesterday on JAMA's Web site revealing that they had asked the Mayo Clinic College of Medicine to investigate.