Dose–response effect of statins on colorectal cancer risk in IBD: a nationwide cohort study

Patients with inflammatory bowel disease (IBD) face an elevated risk of colorectal cancer (CRC). Statins have demonstrated potential anticancer properties, but evidence in IBD populations remains limited. To evaluate the association between sustained statin use and the risk of CRC in patients with IBD, and to assess dose–response relationships and statin type-specific effects. Nationwide, retrospective cohort study using time-dependent Cox proportional hazards models and Fine–Gray competing risk models. Among 6,120 propensity score–matched adults with IBD (2,040 statin users and 4,080 non-statin lipid-lowering agent users), statin use was associated with a 65% reduction in CRC risk compared with users of non-statin lipid-lowering agents (adjusted hazard ratio aHR 0.35; 95% CI, 0.24–0.52; p<0.0001). A clear dose–response relationship was observed, with the highest quartile of cumulative exposure associated with an aHR of 0.08. Rosuvastatin and simvastatin conferred the strongest protective effects. Statin use also correlated with lower all-cause mortality (aHR 0.42; 95% CI, 0.35–0.51). In this nationwide observational cohort, sustained statin use was associated with a significantly lower risk of CRC and mortality. While the observed dose–response and statin-specific patterns suggest a potential chemopreventive signal, these findings are hypothesis-generating. Confirmation in randomized or pragmatic trials is required before these results can translate into clinical practice.