Background: Human immunodeficiency virus (HIV) infection depletes CD4+ lymphocytes, which may benefit patients with inflammatory bowel disease (IBD). The aim was to compare the course of IBD in HIV patients with a matched group of IBD seronegative patients.
Methods: A total of 20 IBD (14 Crohn's disease, 6 ulcerative colitis) HIV infected patients and 40 matched control seronegative IBD patients (2 controls per case) were compared regarding relapse of their disease. The CD4+ count was followed every 6 months and a value of < or =500 cells/microL was used to define patients with immunosuppression. Relapse rates per year of follow-up were compared among the 2 groups and survival curves for cumulative remission rates were compared with a log-rank test. Multivariate analysis was used to discriminate among the impact of different variables on the risk of IBD relapse.
Results: The median duration of follow-up was 8.4 years (range 0.6-18 years). The mean relapse rate for the HIV+IBD group was 0.016/year of follow-up as compared to 0.053/year of follow-up for the IBD-matched control group (P = 0.032). Regarding the HIV-positive/IBD group, 14 patients were immunosuppressed at any given time during the follow-up period. None of these patients experienced an IBD relapse, whereas 3 out of the 6 without immunosuppression relapsed (P = 0.017). According to the multivariate analysis, HIV status was the only risk factor independently associated with a lower probability of IBD relapse.
Conclusions: HIV infection reduces the relapse rates in IBD patients and this may be attributed to the lower CD4+ counts seen in these patients.