Mannitol for the prevention of cisplatin-induced nephrotoxicity: A retrospective comparison of hydration plus mannitol versus hydration alone in inpatient and outpatient regimens at a large academic medical center

Background Cisplatin-induced nephrotoxicity is a dose limiting adverse effect that occurs in nearly one-third of patients. Mannitol administration has been used as a means to negate this toxicity. Data regarding the efficacy of mannitol use in this context are conflicting and limited. Objective The aim of this study is to evaluate the effect of mannitol on renal function and describe the incidence of cisplatin-induced nephrotoxicity. Methods This study is a quasi-experimental retrospective analysis approved by the Institutional Review Board of inpatient and outpatient adults receiving cisplatin doses ≥40 mg/m2. The primary outcome was mean change in serum creatinine from baseline. Secondary outcomes included incidences of various grades of nephrotoxicity. Results A total of 313 patients (95 treated with mannitol and 218 without) were evaluated. The average increase in serum creatinine (mg/dL) was lower in patients who received mannitol versus those who did not (0.30 vs. 0.47; 95% confidence interval for difference, 0.03 to 0.31; P = 0.02). Grade 2 or higher nephrotoxicity occurred less frequently in patients who received mannitol versus those who did not (8% vs. 17%; P = 0.04). Non-gynecologic regimens and those who received doses ≥70 mg/m2 of cisplatin had lower rates of grade 2 or higher nephrotoxicity with mannitol (6% vs. 23%; P = 0.001, and 7% vs. 22%; P = 0.03, respectively). Conclusion The use of mannitol reduces the incidence and severity of nephrotoxicity in patients treated with cisplatin. The results of the study suggest mannitol may be most effective when used with non-gynecologic regimens and with cisplatin doses ≥70 mg/m2.