N-acetylcysteine Plus Hydration For Prevention Of Contrast-induced Nephropathy: Systematic Review And Meta-analysis

Objective: Contrast-induced nephropathy (CIN) has become one of thecommon causes of in-patients with acute kidney injury， therefore,prevention of CIN is a focus of clinical attention nowadays. N-acetylcysteine (NAC) has been the most closely watched drugs used in theprevention of CIN, but its role remains controversial. We conducted asystermatic review to access the efficacy and safety of NAC plus hydrationfor prevention of CIN in order to provide a scientific basis for clinicalrational use NAC.Method: According to the inclusive criteria and exclusive criteria,relevant studies published up to January31,2013that investigated theefficacy of NAC plus hydration for preventing CIN were systematicallysearched by the databases PubMed, Embase, and the Cochrane Library.Screening qualified studies, using the Cochrane Collaboration’s tool forassessing risk of bias, a systematic review and meta-analysis was performedusing the statistical software Review Manager Version5.1. Results: Thirty-nine randomized controlled trials (RCTs) wereidentified, providing data for7280patients. Compared with hydration orplacebo plus hydration, the meta-analysis of RCTs showed oral NAC plushydration can effectively reduce the risk of CIN (RR=0.80;95%CI,0.69-0.94; P=0.006) and intravenous NAC plus hydration can reduce therisk of CIN (RR=0.57;95%CI,0.34-0.95; P=0.03). The results alsodisplayed a significantly effect of standard dose NAC plus hydration for theprevention of CIN (RR=0.58;95%CI,0.48-0.71; P<0.00001), while highdose NAC plus hydration failed to reduce the risk of CIN (RR=0.71;95%CI,0.49-1.03; P=0.07). The results also indicated a significant effect ofNAC plus hydration in patients with underlying renal insufficiency for theprevention of CIN (RR=0.64;95%CI,0.51-0.81; P=0.0001), while NACplus hydration in patients with diabetes failed to reduce the risk of CIN(RR=0.87;95%CI,0.71-1.07; P=0.17). Moreover, the research inllustrateda significantly effect of standard dose NAC plus hydration in patientsunderlying renal insufficiency with low-osmolality/isotonic contrastmedium for the prevention of CIN (RR=0.55;95%CI,0.43-0.69;P<0.00001). NAC plus hydration showed no statistical significance ofadverse events and end point events (P>0.05).Conclusion: The meta-analysis of RCTs revealled effective preventionof oral NAC plus hydration for CIN, a certain prevention effect ofintravenous NAC plus hydration for CIN, significant effect of standard dose NAC plus hydration for the prevention of CIN, and significant effect ofNAC plus hydration in patients with underlying renal insufficiency for theprevention of CIN. The results also detected a significant effect of standarddose NAC plus hydration in patients underlying renal insufficiency withlow-osmolality/isotonic contrast medium for the prevention of CIN. But theresults of high dose NAC or NAC in patients with diabetes were notdisplayed the prevention of CIN. There is no current evidence that NACplus hydration can alter the adverse events and end point events. In short, acertain dose of NAC has prevention effect of CIN in part of population withsecurity in clinical use. Because of the quality of the original documents inthis study and some implement of the research programmes design, it makesthis conclusion has certain limitations. Therefore, some large sample, highquality, multi-center, randomized controlled trials aiming at different studypopulations, different route of administration and dose, and different types ofcontrast medium are required to more adequately assess the role of NAC forthe prevention of CIN in order to provide scientific basis for reasonable useof NAC and guide the clinical prevention of CIN correctly.