Background: Elevated serum cholesterol levels may stimulate proliferation in adenomatous polyps (AP). Our aim was to determine how a reduction of low-density lipoprotein (LDL) cholesterol levels in patients taking statins influences the incidence of APs.
Methods: We performed a retrospective study of patients taking statins who were found to have > or =1 APs on an index colonoscopy, and who also had a follow-up colonoscopy within 3 to 5 years. Patients were divided into 2 groups: (1) those with > or =30% reduction in LDL levels and (2) those with < 30% reduction in LDL levels during the interval between colonoscopies. Univariate and multivariate analysis were evaluated for their association with advanced APs.
Results: We identified 231 patients. Univariate analysis showed that patients with > or =30% LDL reduction had fewer mean total numbers of APs (2.6 versus 3.3, P = 0.02), fewer advanced APs (14% versus 26%, P = 0.04), and smaller APs (5 mm versus 6.1 mm, P = 0.01) than those with <30% reduction in LDL. Multiple logistic regression analysis confirmed that > or =30% LDL reduction was associated with smaller APs (P < 0.01). Subjects with > or =30% LDL reduction also had a 53% reduced incidence of advanced APs (OR, 0.47; CI, 0.22-0.96; P < 0.05). These findings remained significant even when adjusted for nonsteroidal antiinflammatory drug use, age, family history of APs, and body mass index.
Conclusions: A reduction in LDL levels of > or=30% during a 3- to 5-year period of statin therapy was associated with a 53% reduction in the incidence of advanced APs, even after adjustment for other known polyp risk factors.