***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: We included seven studies (662 participants) in this review. All except one study was assessed as being at high risk of bias. Three studies assessed atorvastatin, three assessed simvastatin and one investigated rosuvastatin. All studies collected data during the immediate perioperative period only; data collection to hospital discharge and postoperative biochemical data collection ranged from 24 hours to 7 days. Overall, pre-operative statin treatment was not associated with a reduction in postoperative AKI, need for RRT, or mortality. Only two studies (195 participants) reported postoperative SCr level. In those studies, patients allocated to receive statins had lower postoperative SCr concentrations compared with those allocated to no drug treatment/placebo (MD 21.2 µmol/L, 95% CI -31.1 to -11.1). Adverse effects were adequately reported in only one study; no difference was found between the statin group compared to placebo. Analysis of currently available data did not suggest that preoperative statin use is associated with decreased incidence of AKI in adults after surgery who required cardiac bypass. Although a significant reduction in SCr was seen postoperatively in people treated with statins, this result was driven by results from a single study, where SCr was considered as a secondary outcome. The results of the meta-analysis should be interpreted with caution; few studies were included in subgroup analyses, and significant differences in methodology exist among the included studies. Large high quality RCTs are required to establish the safety and efficacy of statins to prevent AKI after cardiac surgery.
Output:

This review aims to evaluate evidence on the use of statins at the time of heart surgery to investigate if use can help to prevent kidney failure and how well statins are tolerated among patients. We searched the literature to January 2015 and included seven studies that involved a total of 662 participants to inform our assessment. In these studies, patients planned for heart surgery received statins or placebo (or no treatment at all). Five studies (467 participants) reported rates of kidney failure. We found that there was a high risk of bias in six of the seven included studies. We found no difference in the rate of kidney failure between patients who received statins and those who did not. Two studies (195 patients) reported serum creatinine (a marker of kidney function) after the operation. We found that serum creatinine was lower in patients in the statin group (indicating better kidney function). Other conclusions were limited by the small number of studies. However, patients who received statins did not seem to need less dialysis. They did not have a higher rate of death in hospital and did not have an increased rate of adverse events.