To Örebro University

BACKGROUND: Statins reduce the risk of inflammatory bowel disease (IBD), however their effect on IBD disease progression is largely unknown.

METHODS: We linked Swedish healthcare registers and performed a nationwide cohort study (2006-2020) of 19 788 adults (≥18 years) with ulcerative colitis (UC) and 12 582 with Crohn's disease (CD). Of these, 1733 with UC and 962 with CD were identified as incident statin users after UC or CD diagnosis. After 1:1 propensity score matching, we compared statin users with non-users to estimate the risk of IBD-related surgery, hospitalizations, and disease flares expressed as incidence rates (IRs) and multivariable-adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs). For outcomes with statistically significant estimates, we calculated the numbers needed to treat (NNT).

RESULTS: During a median follow-up of 3.4 years we observed a reduced risk of IBD-related surgery in statin users (UC, IR: 3.4 [95%CI: 2.1-4.8] per 1000 person-years; CD, IR: 9.2 [6.2-12.2]) compared with non-users in UC (IR: 6.3 [4.2-8.5]; aHR: 0.55 [0.31-0.97]) and CD (IR: 15.4 [11.0-19.7]; aHR: 0.54 [0.33-0.88]). The NNT to avoid one IBD-related surgical event per year of statin treatment were 345 (UC) and 161 (CD). For statin users, the risks of hospitalizations (IR: 17.0 [13.9-20.2]; aHR: 0.68 [0.51-0.91]) and disease flares (IR: 207.4 [193.2-221.6]; aHR: 0.86 [0.77-0.97]) were reduced in UC, but not in CD (IR: 20.3 [15.8-24.9]; aHR: 0.78 [0.56-1.09] and IR: 245.5 [223.9-267.1]; aHR: 1.02 [0.88-1.19]). In UC, NNT for hospitalizations and disease flares were 145 and 15.

CONCLUSIONS: Statins were associated with a reduced risk of IBD-related surgery, hospitalizations, and disease flares in patients with UC, and with a reduced risk of IBD-related surgery in patients with CD.