PS-C18-7: EFFECT OF TOLVAPTAN IN PATIENTS WITH CHRONIC KIDNEY DISEASE STAGE G5 AND IMPACT OF CONCOMITANT USE OF THIAZIDE DIURETICS

Abstract

Objective: Tolvaptan, a vasopressin V2 receptor antagonist, is used to treat congestive heart failure (CHF). Its diuretic effect in patients with severe renal dysfunction remains poorly characterized. Thiazide diuretics decrease urinary volume (UV) in patients with nephrogenic diabetes insipidus, in which V2 receptor function is absent. Likewise, thiazide diuretics may decrease UV in patients receiving tolvaptan. Design and method: This retrospective cohort study included inpatients with chronic kidney disease stage G5, in whom tolvaptan was administered for CHF. UVs at 24-h pre- and post-tolvaptan administration as well as 30-day dialysis initiation were compared between patients with and without thiazide diuretics. Results: Thiazide diuretics were used in 26 of 106 recruited patients (73.4 ± 13.0 years, estimated glomerular filtration rate: 8.07 ± 3.13 mL/min/1.73 m2). In contrast to those who received thiazide diuretics (1177.3 ± 686.5 vs. 1173.1 ± 629.1 mL/day, p = 0.93), patients without thiazide diuretics had significantly higher 24-h UV pre- and post-tolvaptan administration (1043.4 ± 645.6 vs. 1422.2 ± 774.0 mL/day, p < 0.001). In a multivariate regression model, the use of thiazide diuretics was significantly associated with decreased 24-h UV (beta coefficient, -486.7 [95% confidence interval (CI), -674.5 to -298.8]) and increased urine osmolality (beta coefficient, 37.7 [95% CI, 17.1–58.4]), bodyweight (beta coefficient, 0.62 [95% CI, 0.31–0.92]) and 30-day dialysis initiation (odds ratio 3.40 [95% CI, 1.18–9.82]) after tolvaptan administration. Conclusions: Tolvaptan had significant diuretic effects on patients with CHF, even in those with severe renal dysfunction. Concomitant use of thiazide diuretics diminished these effects.