Factors influencing first relapse in patients with Crohn's disease.

To determine whether information available at time of diagnosis of Crohn's disease can predict initial clinical course, I followed 239 patients prospectively from time of diagnosis to initial relapse. The patient's sex, smoking habits, contraceptive usage, disease extent, and presence of granulomas in the first histological specimen were recorded. No association was found between this demographic data and the interval between onset of symptoms and diagnosis, the severity of symptoms at presentation, or the time to relapse. The type of relapse, however, was influenced by the type of the first attack; 70% of relapses were of the same type as the initial attack. Cigarette smoking was associated with ileocolitis (p = 0.028). There was a trend for oral contraceptive users to have ileocolitis, whereas the presence of granulomas in the first histological specimen was not associated with a specific disease distribution. Patients with ileocolitis had more inflammatory attacks than those with ileitis or colitis (p = 0.001). There was also a trend for cigarette smokers and those on oral contraceptives to have more inflammatory attacks, but the presence of granulomas had no effect on the type of relapse. There is little to assist in prognosis of early disease when the diagnosis of Crohn's disease is first made, although the types of attacks tend to repeat themselves.