5-Aminosalicylates, sulfasalazine, steroid use, and complications in patients with ulcerative colitis

The choice between sulfasalazine and 5-aminosalicylate (5-ASA) drugs in the management of patients with ulcerative colitis often depends on idiosyncrasies of drug tolerance and control of the disease in individual patients. We sought to evaluate whether there were population differences in the effect of 5-ASA and sulfasalazine on the occurrence of clinically recognized adverse events. We also attempted to determine whether there were differences in the use of concomitant steroids and in the rates of hospitalization.

We reviewed a large computerized database drawn from general practices in the United Kingdom. There we found records of 2894 patients in whom general practitioners had diagnosed ulcerative colitis, and who were receiving ongoing medical therapy specific to ulcerative colitis. The period of data availability ran from the beginning of 1990 to the latter part of 1993. The average duration of observation was 2.1 yr per patient. Patient histories were categorized into distinct periods according to the dose of 5-ASAs and sulfasalazine, steroids, and immunosuppressants, and were further separated according to the activity of ulcerative colitis. Within these categories, we examined the initiation and discontinuation of steroids, incidence of new hospitalizations for ulcerative colitis, and clinical mention of adverse events.

New clinical mentions of hepatic, pancreatic, renal, and hematological events other than anemia were similar among the 5-ASAs and were very infrequent overall. Hospitalizations for ulcerative colitis occurred with similar frequency (about 15 hospitalizations per 100 patients per year) among users of those drugs. Patients receiving sulfasalazine had lower rates of initiation of prednisolone than did patients receiving 5-ASA, but sulfasalazine was used proportionately less often in patients who had been recently hospitalized, and it may be that sulfasalazine patients were somewhat less sick, overall, than were 5-ASA-using patients. The choice of drug did not affect discontinuation rates for prednisolone among established users.

In the United Kingdom, during the period of this study, serious adverse reactions to drugs were not an important aspect of the management of patients with ulcerative colitis. Renal and pancreatic complications of sulfasalazine and 5-ASA therapy were extremely rare. Sulfasalazine and 5-ASA drugs have similar steroid-sparing properties. Disease-specific hospitalizations are approximately 100 times more common in ulcerative colitis patients than are serious adverse drug effects. Considerations of drug efficacy should therefore dominate the choice between therapeutic agents.