Risk factors for renal impairment in patients with solid tumors or multiple myeloma treated with zoledronic acid

Objective: Using retrospective prescription analysis, this study aimed to investigate the risk factors for renal impairment among adult solid tumor and multiple myeloma patients who have received zoledronic acid injections in a teaching hospital over the last 4 years. Methods: We examined solid tumor and multiple myeloma patients who had received at least one zoledronic acid injection in a teaching hospital in Seoul with at least 2,000 beds over the 4 years between January 2008 and December 2011. The injection histories and serum creatinine levels of these patients were included in the analysis. Patients who developed renal impairment subsequent to zoledronic acid injection were identified, and the risk factors were statistically analyzed. Results: In only 1 case zoledronic acid injection was reduced as directed by the creatinine clearance guidelines. Four patients whose creatinine clearance was less than 30 ml/min were injected with zoledronic acid even though its use is contraindicated in this situation. Of the 338 research subjects, 26 developed renal impairment. The following were confirmed to be statistically significant (p < 0.05) risk factors for the development of renal impairment: serum creatinine (at first injection) of greater than 1.4 mg/dl, diabetes, hypertension, thalidomide prescription, multiple myeloma, and previous pamidronate usage. Conclusions: Based on the results of this study, renal monitoring is necessary following zoledronic acid injection. In addition, for patients with renal impairment risk factors, a risk-benefit analysis must be performed before zoledronic acid is administered, and it must be administered at an appropriate dose according to the level of renal function.