The circadian defect in plasma vasopressin and urine output is related to desmopressin response and enuresis status in children with nocturnal enuresis.
Level 4 - case-series / case-control
Prospective physiological cohort / case series without a healthy control group
PubMed 18433780 · doi:10.1016/j.juro.2008.01.171
What was done
Inpatient circadian rhythm studies were conducted in 125 children aged 6 to 17 years (mean age 10.4 ± 3 years) with monosymptomatic nocturnal enuresis under standardized fluid intake, evaluating plasma arginine vasopressin (AVP) across 7 blood sampling times and urine output across 6 collection periods. Subsequently, 78 of these patients completed a 4-week home monitoring phase measuring nocturnal urine volume by diaper weighing (2 weeks untreated baseline followed by 2 weeks of bedtime desmopressin titration from 20 to 40 µg) to correlate circadian AVP and urine profiles with enuresis status, desmopressin response, age, and gender.
What was found
All patient subgroups demonstrated an attenuated circadian AVP rhythm, with females generally showing lower plasma AVP levels across the circadian cycle than males. Desmopressin responders with an enuretic episode during the inpatient study had the highest nocturnal urine excretion rates and the most severe AVP deficiency. Nocturnal urine volume was significantly higher on wet nights than dry nights, both in the inpatient setting and during home diaper recordings; increased sodium excretion contributed to this nocturnal polyuria. The abstract reports no exact numerical values, confidence intervals, or p-values.
Why it matters
The findings confirm that nocturnal AVP deficiency driving nocturnal polyuria underlies a distinct subgroup of children with enuresis who respond to desmopressin, highlighting the value of measuring wet-night urine production prior to selecting treatment.
Limits
No healthy, non-enuretic control group was included for comparison. Only 78 of the 125 enrolled patients participated in the home treatment phase, which was open-label without a placebo control. The abstract does not provide specific numerical measurements, variance estimates, or statistical significance levels.
Cited by
- supports Bedwetting and nighttime urination problems in young children occur because the hormone vasopressin has not fully developed yet.