BACKGROUND: People with chronic kidney disease (CKD) have higher risks of 
cardiovascular disease compared to the general population. Specifically, 
cardiovascular deaths account most deaths in kidney transplant recipients. 
Statins are a potentially beneficial intervention for kidney transplant patients 
given their established benefits in patients at risk of cardiovascular disease 
in the general population. This is an update of a review first published in 
2009.
OBJECTIVES: We aimed to evaluate the benefits (reductions in all-cause and 
cardiovascular mortality, major cardiovascular events, myocardial infarction and 
stroke, and progression of CKD to requiring dialysis) and harms (muscle or liver 
dysfunction, withdrawal, cancer) of statins compared to placebo, no treatment, 
standard care, or another statin in adults with CKD who have a functioning 
kidney transplant.
SEARCH METHODS: We searched the Cochrane Renal Group's Specialised Register to 
29 February 2012 through contact with the Trials Search Co-ordinator using 
search terms relevant to this review.
SELECTION CRITERIA: We included randomised controlled trials (RCTs) and 
quasi-RCTs that compared the effects of statins with placebo, no treatment, 
standard care, or statins on mortality, cardiovascular events, kidney function 
and toxicity in kidney transplant recipients.
DATA COLLECTION AND ANALYSIS: Two authors independently extracted data and 
assessed risk of bias. Treatment effects were expressed as mean difference (MD) 
for continuous outcomes (lipids, glomerular filtration rate (GFR), proteinuria) 
and relative risk (RR) for dichotomous outcomes (major cardiovascular events, 
mortality, fatal or non-fatal myocardial infarction, fatal or non-fatal stroke, 
elevated muscle or liver enzymes, withdrawal due to adverse events, cancer, 
end-stage kidney disease (ESKD), acute allograft rejection) together with 95% 
confidence intervals (CI).
MAIN RESULTS: We identified 22 studies (3465 participants); 17 studies (3282 
participants) compared statin with placebo or no treatment, and five studies 
(183 participants) compared two different statin regimens.From data generally 
derived from a single high-quality study, it was found that statins may reduce 
major cardiovascular events (1 study, 2102 participants: RR 0.84, CI 0.66 to 
1.06), cardiovascular mortality (4 studies, 2322 participants: RR 0.68, CI 0.45 
to 1.01), and fatal or non-fatal myocardial infarction (1 study, 2102 
participants: RR 0.70, CI 0.48 to 1.01); although effect estimates lack 
precision and include the possibility of no effect.Statins had uncertain effects 
on all-cause mortality (6 studies, 2760 participants: RR 1.08, CI 0.63 to 1.83); 
fatal or non-fatal stroke (1 study, 2102 participants: RR 1.18, CI 0.85 to 
1.63); creatine kinase elevation (3 studies, 2233 participants: RR 0.86, CI 0.39 
to 1.89); liver enzyme elevation (4 studies, 608 participants: RR 0.62, CI 0.33 
to 1.19); withdrawal due to adverse events (9 studies, 2810 participants: RR 
0.89, CI 0.74 to 1.06); and cancer (1 study, 2094 participants: RR 0.94, CI 0.82 
to 1.07).Statins significantly reduced serum total cholesterol (12 studies, 3070 
participants: MD -42.43 mg/dL, CI -51.22 to -33.65); low-density lipoprotein 
cholesterol (11 studies, 3004 participants: MD -43.19 mg/dL, CI -52.59 to 
-33.78); serum triglycerides (11 studies, 3012 participants: MD -27.28 mg/dL, CI 
-34.29 to -20.27); and lowered high-density lipoprotein cholesterol (11 studies, 
3005 participants: MD -5.69 mg/dL, CI -10.35 to -1.03).Statins had uncertain 
effects on kidney function: ESKD (6 studies, 2740 participants: RR 1.14, CI 0.94 
to 1.37); proteinuria (2 studies, 136 participants: MD -0.04 g/24 h, CI -0.17 to 
0.25); acute allograft rejection (4 studies, 582 participants: RR 0.88, CI 0.61 
to 1.28); and GFR (1 study, 62 participants: MD -1.00 mL/min, CI -9.96 to 
7.96).Due to heterogeneity in comparisons, data directly comparing differing 
statin regimens could not be meta-analysed. Evidence for statins in people who 
have had a kidney transplant were sparse and lower quality due to imprecise 
effect estimates and provided limited systematic evaluation of treatment harm.
AUTHORS' CONCLUSIONS: Statins may reduce cardiovascular events in kidney 
transplant recipients, although treatment effects are imprecise. Statin 
treatment has uncertain effects on overall mortality, stroke, kidney function, 
and toxicity outcomes in kidney transplant recipients. Additional studies would 
improve our confidence in the treatment benefits and harms of statins on 
cardiovascular events in this clinical setting.