Hypokalemia, hypomagnesemia, and hyponatremia are associated with acute kidney injury in patients treated with cisplatin.

e24105 Background: Cisplatin-associated acute kidney injury (C-AKI) is common. Predictive factors of C-AKI include age > 60 years, hypertension, cisplatin dose, diabetes, and serum albumin < 3.5g/L. The association between C-AKI and hypokalemia, hypomagnesemia or hyponatremia has not been well characterized to date. Methods: Data from a previous retrospective observational study was obtained. Patients who received at least one dose of cisplatin between September 2010 and December 2016 at the Centre Hospitalier de l’Université de Montréal were included. Patients were separated into 3 groups with similar cisplatin doses and schedules. Group A received cisplatin 60-100 mg/m2 q 3 weeks with laboratories before day 1, group B received cisplatin 60-75 mg/m2 q 3 weeks with laboratories before days 1 and 8 of each cycle and group C had weekly cisplatin 40 mg/m2 and laboratories. Association between hypomagnesemia, hypokalemia, hyponatremia, and risk of AKI, as defined by KDIGO criteria, was determined using a counting process specification of Cox’s regression models. These were used to estimate hazard ratio (HR) of AKI incidence with 95% confidence intervals (CI) of patients with and without cisplatin-induced electrolyte disorders. Estimates were adjusted for confounding factors such as volume of hydration (3 or 4 L), fluids (D5/0.45 NS or NS), age, sex, presence of furosemide and mannitol. Results: A total of 1305 patients were separated in group A (714 pts), B (205 pts) and C (386 pts). The proportion of patients with at least one event of hypokalemia, hypomagnesemia or hyponatremia was lower in group A (29.1%, 57.7% and 36.3%) compared to group B (43.4%, 66.8%, 60.0%) and group C (48.7%, 78.6%, 50.8%). The incidence of all grade C-AKI was 35.7% (group A), 46.8% (group B), 18.2% (group C). The HR of C-AKI based on each electrolyte disorder per group is presented in table I. Conclusions: The presence of one event of hypokalemia, hypomagnesemia, or hyponatremia was significatively associated with increased risk of C-AKI only in group A. This could be related to the higher average dose per cycle in this group. Other studies are needed to characterize the presence of an electrolyte disorder as a risk factor that can predict the risk of C-AKI in this subpopulation. [Table: see text]