Is there a gender difference in antidiuretic response to desmopressin in children?

Abstract

Women with nocturia are more sensitive to desmopressin, a synthetic arginine vasopressin (AVP) analogue, with significant antidiuretic responses to desmopressin orally disintegrating tablet (ODT) 25 μg, compared with men who require 58 μg to achieve similar responses. In children the current desmopressin dose recommendation to treat primary nocturnal enuresis (PNE) is the same for boys and girls. This post hoc analysis of data from a randomised, doubleblind single-dose study of 84 children with PNE aged 6 -12 years explored gender differences in sensitivity to desmopressin in children. Following water loading to suppress endogenous AVP, placebo or desmopressin 30, 60, 120, 240, 360 or 480 μg was administered when urinary production reached >0.13 mL/min/kg. The endpoints of urinary osmolality and duration of urinary-concentrating action (DOA) (above three thresholds: 125, 200 and 400 mOsm/kg) were analysed to compare efficacy in boys and girls, in each treatment group. The DOA and urinary osmolality were similar in both genders in the desmopressin 120 -480 µg groups. Boys receiving desmopressin ODT 30 -60 µg tended to increased urinary osmolality and experienced 1 -2 hours longer DOA than girls. The same pattern of higher values in boys compared with girls was seen for all measures of urinary osmolality. Conclusion: In a limited sample of pre-pubertal children the antidiuretic response to desmopressin was largely similar between genders, in contrast to findings in adults.