Patients undergoing haemodialysis have a greatly increased risk of premature cardiovascular disease. However, the relationship between cardiovascular disease and conventional risk factors is inconsistent in such patients and the benefits of lipid-lowering therapy are uncertain. Patients with advanced renal disease often have low/normal LDL cholesterol levels, but observational studies have suggested that benefit can still be obtained from statin therapy.

The AURORA (A Study to Evaluate the Use of Rosuvastatin in Subjects on Regular Hemodialysis) study was a randomized, double-blind, placebo-controlled multicentre trial consisting of 2773 subjects with end-stage renal disease who had been treated with haemodialysis or haemofiltration for at least three months. Patients were divided into a Rosuvastatin group (10 mg daily) and a placebo group. The trial primary endpoints were death from cardiovascular causes, non-fatal myocardial infarction or non-fatal stroke and the secondary endpoints included death from all causes and individual cardiac and vascular events. Although subjects taking Rosuvastatin demonstrated a mean LDL-cholesterol concentration reduction of 43%, there was no significant effect of Rosuvastatin treatment on cardiac disease. In addition, there was no significant effect of treatment on any of the secondary endpoints.

These findings are in agreement with the only other large-scale study (4D study) looking at benefits of statin therapy in haemodialysis patients. The results from AURORA suggest that cardiovascular disease in haemodialysis patients may differ from that of those with less severe kidney disease. In the latter group of patients, several trials have shown a beneficial effect of statin treatment. This raises the possibility that the beneficial effect of statin treatment is reduced as kidney disease worsens, an issue that may be addressed by the forthcoming SHARP study which is evaluating benefits of simvastatin and ezetimibe in patients across the renal function spectrum.

A commentary by Strippoli and Craig in the same issue discusses some of the questions raised by the AURORA study. Although some possible flaws in the study were examined, it was the opinion of the authors that the results were likely to be explained by differences in the causal pathway for early cardiovascular events between patients on haemodialysis and the general population. Cardiac disease differs between populations with atheromatous coronary lesions predominating in the general population, compared with left ventricular hypertrophy and aortic calcification in patients undergoing dialysis. Statin therapy and lipid lowering may therefore not be useful in treating the majority of cardiovascular disease found in dialysis patients.

Although the AURORA study showed no evidence of adverse affects of Rosuvastatin treatment, the benefits of treatment were negligible. This demonstrates the lack of effective interventions to lower cardiovascular risk in patients undergoing haemodialysis. The search for more effective treatments may require a more complete understanding of the causal pathways of cardiac disease in these patients.