HONOLULU — Two good reasons exist for all ulcerative colitis patients to be on 5-aminosalicylate long term, Dr. Bret A. Lashner said at the annual meeting of the American College of Gastroenterology.
One is that the drug helps maintain disease remission. That's common knowledge. But 5-ASA also may reduce the risk of developing colorectal cancer (CRC), said Dr. Lashner, director of the Center for Inflammatory Bowel Disease at the Cleveland Clinic Foundation.
The evidence for a CRC chemopreventive effect of 5-ASA is “somewhat weak,” he conceded. There have been five studies addressing the issue, all observational. Three proved positive, and two showed no effect.
But a recent metaanalysis by Dr. Fernando S. Velayos and coworkers at the University of California, San Francisco, that included these five studies as well as four others looking at the combined end point of CRC or dysplasia, concluded 5-ASA was indeed protective against CRC. The drug was associated with a 49% reduction in relative risk. It was also associated with an identical 49% reduction in the risk of CRC/dysplasia (Am. J. Gastroenterol. 2005;100:1345–53).
“Of course, we already recommend 5-ASA to our ulcerative colitis patients for maintenance of their remission, which they should take. But we now know from work at the University of Chicago that patients don't take this medication the way that they should. Adding into your practice the advice that 5-ASA not only prevents recurrence but might help decrease the risk of cancer or dysplasia might get patients to take their medicine more often,” Dr. Lashner said.
Two other agents are supported by evidence of efficacy for primary chemoprevention of CRC in ulcerative colitis patients. One is folic acid at 0.4–1.0 mg/day. Only one of three epidemiologic studies showed a statistically significant benefit, but since folic acid is safe and inexpensive, it is something—like 5 ASA—that ulcerative colitis patients ought to routinely take for the long term, the gastroenterologist continued. The other CRC chemopreventive agent is ursodeoxycholic acid, which in two studies showed efficacy in inflammatory bowel disease patients with primary sclerosing cholangitis.
'We already recommend 5-ASA to our ulcerative colitis patients for maintenance of their remission.' DR. LASHNER