Effectiveness of statins in chronic kidney disease.

Abstract

BACKGROUND
Previous studies show that statins reduce total cholesterol (TC) concentration by both 21% in primary prevention (PP) and secondary prevention (SP) in clinical trials and by ∼24% in the general population. There are few data about the efficacy of statins on TC concentration and cardiovascular (CV) outcome in patients with chronic kidney disease (CKD). We evaluated the reduction of TC concentration and subsequent risk of CV morbidity and mortality with statins in CKD patients.
METHODS
A population-based cohort study using a record-linkage database in Tayside, Scotland. A total of 2369 patients who had a primary diagnosis of CKD from Scottish Morbidity Record data or biochemistry database (serum creatinine of 220 μmol/l or higher) and who had at least two separate TC measurements between 1993 and 2007 were studied. Patients were categorized into statin-exposed and statin-unexposed groups according to statin use status during the follow-up. They were also classified into PP (n = 1325) and SP (n = 1044) cohorts at the entry date. The main outcomes were TC concentration change from baseline, CV events [Antiplatelet Trialist's Collaboration (APTC)] and all-cause mortality during the follow-up. Cox regression models, in which statin use was a time-dependent variable, were employed to assess the risk of outcome and adjusted for other known confounders.
RESULTS
Statin-associated TC concentrations decreased by 0.59 mmol/l (12%) in PP cohort and 0.56 mmol/l (13%) in SP cohort from 4.77 and 4.48 mmol/l at baselines, respectively. Statin use was associated with a reduced risk of APTC events, CV mortality or all-cause mortality in PP {adjusted hazard ratio (HR), 0.65 [95% confidence interval (CI) 0.48-0.88]; 0.73 (95% CI 0.52-0.98); 0.59 (95% CI 0.48-0.73)} and SP [adjusted HR, 0.66 (95% CI 0.52-0.84); 0.60 (95% CI 0.47-0.77); 0.56 (95% CI 0.47-0.68)], respectively.
CONCLUSION
Statin use reduced TC concentrations by ∼13% in patients with CKD. Statins were protective of APTC events, CV mortality and all-cause mortality in patients with or without established CV disease.