Statins and risk of diverticular disease: Nested case-control study

Background Statins exert pleiotropic anti-inflammatory effects and may prevent diverticular disease. However, the association remains poorly understood with previous studies obtaining conflicting results. Aims To examine the effect of statin on the subsequent risk of diverticular disease. Methods We conducted a nested case-control study in Denmark among respondents (>18 years) of the 2010 or the 2013 Danish National Health Survey. Among these, we identified 8809 cases of hospital-diagnosed diverticular disease and risk-set sampled population controls without diverticular disease. Using complete prescription and hospital records, we used conditional logistic regression to compute odds ratios (ORs) associating statin use with diverticular disease. In adjusted analyses, we controlled for hospital-based diagnoses, medication use other than statins, and lifestyle and socioeconomic factors. Results The fully adjusted OR for diverticular disease associated with ever use (>= 1 statin prescription filling) was 1.19 (95% CI: 1.12-1.27) compared with never use. However, we observed no dose-response relation. For example, among short-term users (<5 years), the OR was 1.18 (95% CI: 1.04-1.35) for low intensity users and 1.13 (95% CI: 1.01-1.26) for high intensity users. Among long-term users (>= 5 years), the respective ORs were 1.25 (95% CI: 1.13-1.38) and 1.11 (95% CI: 0.98-1.24). In analyses restricting to cases and controls with a previous colonoscopy, associations were null (OR: 1.01 [95% CI: 0.85-1.20]). Conclusions The observed association of a higher risk of diverticular disease associated with statins could be explained by diagnostic bias. Our study did not support a protective nor harmful effect of statins on the risk of diverticular disease.