Preliminary Experience with Low-dose Desmopressin Treatment and Urinary Arginine Vasopressin Concentration as a Response Predictor for Patients with Nocturia with Nocturnal Polyuria

Objectives: To assess whether urinary arginine vasopressin (AVP) concentrations adjusted for urinary creatinine (Cr) can predict responsiveness to low-dose desmopressin for nocturia with nocturnal polyuria (NP).

Methods: Nine NP patients aged 64-84 years with ≥ 2 nocturnal voids received 2.5 µg of intranasal desmopressin for 4 weeks and were evaluated for its effectiveness. Prior to treatment, urinary AVP/Cr concentrations at first morning void and serum sodium and plasma natriuretic peptide (BNP) concentrations were measured, and all patients underwent 5% hypertonic saline infusion.

Results: Six responders to 2.5 µg desmopressin had average decreases in nocturnal frequency from 3.2 to 1.8 voids nightly and in nocturnal diuresis by 40%, without clinically significant adverse events. Non-responders remained unaffected even with dose escalation to 5.0 µg desmopressin. For responders, urinary AVP/Cr concentrations were less than 14 pg/mg · Cr, which is lower than in non-responders. Within a physiological range of plasma osmolality, plasma AVP release in response to 5% hypertonic saline infusion was less in responders than in non-responders. Blood pressure measurements and BNP concentrations were unchanged.

Conclusions: Urinary AVP/Cr at first morning void may have potential clinical value as a predictor for responsiveness to low-dose desmopressin in nocturia with NP.