The effect of cholesterol reduction with cholestyramine on renal function

Background: Epidemiological studies suggest that dyslipidemia is an independent risk factor for the development of renal insufficiency in otherwise healthy individuals. Yet, data on the effect of cholesterol reduction are lacking in this population. We performed a secondary analysis of a large existing cohort to determine whether treatment with cholestyramine improved renal function compared with placebo. Methods: A total of 3,603 middle-aged men from the Lipid Research Clinics Coronary Primary Prevention Trial comprised the study group: 1,806 men were randomly assigned to treatment with cholestyramine, and 1,797 men, placebo. The primary outcome is difference in glomerular filtration rates between the 2 groups. Results: A total of 1,806 men were randomly assigned to treatment with cholestyramine, and 1,797 men, placebo. For the entire group, the estimated mean difference in glomerular filtration rates between the cholestyramine and placebo groups was 0.39 mL/min/1.73 m² (0.007 mL/s/1.73 m²; P = 0.28) during a follow-up period of more than 8 years. Conclusion: Cholesterol reduction with cholestyramine treatment did not meaningfully affect renal function compared with placebo in the present analysis. Prospective intervention trials are needed to determine whether decreasing serum cholesterol levels benefits kidney function in otherwise healthy individuals.