Long-term Statin Use and the Risk of Gallstone Disease: A Population-based Case-Control Study

Abstract

Most gallstones originate from cholesterol-supersaturated bile. Statins inhibit hepatic cholesterol biosynthesis and therefore may reduce the risk of gallstone disease. Population-based evidence, however, is sparse. Thus, the authors conducted a population-based case-control study using medical databases from northern Denmark (1.7 million inhabitants) to identify 32,494 cases of gallstones occurring between 1996 and 2008 and to identify age-, sex-, and county-matched population controls for each case. Cases and their matched controls who were exposed to lipid-lowering drugs were categorized as current users if their last prescription was redeemed ≤90 days before the case's diagnosis date; otherwise, they were categorized as former users. Conditional logistic regression was used to estimate adjusted odds ratios and 95% confidence intervals for gallstone disease in patients treated with lipid-lowering drugs. In current users, the adjusted odds ratios associating statin use with the occurrence of gallstone disease were 1.17 (95% confidence interval (CI): 1.06, 1.30) for those who had 1-4 prescriptions, 0.89 (95% CI: 0.80, 0.97) for those who had 5-19 prescriptions, and 0.76 (95% CI: 0.69, 0.84) for those who had ≥20 total prescriptions. In former users, the corresponding adjusted odds ratios were 1.24 (95% CI: 1.11, 1.39), 0.97 (95% CI: 0.86, 1.10), and 0.79 (95% CI: 0.64, 0.97), respectively. The use of other lipid-lowering drugs showed no similar association.