Tolvaptan Reduces Long-Term Total Medical Expenses and Length of Stay in Aquaporin-Defined Responders

The vasopressin type-2 antagonist tolvaptan (TLV) has clinical advantages including amelioration of congestion and normalization of hyponatremia in patients with decompensated heart failure (HF). However, there have been no studies on the cost-effectiveness of TLV therapy. We enrolled 60 consecutive hospitalized patients with stage D HF who received TLV [TLV (+) group], and 60 propensity score-matched HF patients without TLV treatment [TLV (-) group]. We excluded 54 patients who died or received cardiac replacement therapy within 1 year, and finally enrolled 32 patients who received TLV and 34 who did not, who were followed for > 1 year. Among 45 aquaporin-defined responders, whose urine aquaporin-2 relative to plasma arginine vasopressin level was > 1.4 x 10(3) L/g Cre, the TLV (+) group required significantly lower total medical expenses and shorter lengths of stay (LOS) compared with the TLV (-) group [11.2 (1.2-33.3) versus 31.2 (2.2-71.4) x 10(5) JPY/year, P < 0.001; 30 (0-304) versus 70 (20-221) days, P = 0.030]. In contrast, among the remaining 21 aquaporin-defined non-responders, medical expenses and LOS were comparable irrespective of TLV administration (P = 0.087 and P = 0.407). In conclusion, TLV therapy may reduce total medical expenses in aquaporin-defined responders with stage D HF.