Abnormal Sleep Architecture and Refractory Nocturnal Enuresis

Purpose: The relation between sleep and nocturnal enuresis has been an area of discussion for many years. Children with enuresis are generally believed to have sleep that is too deep with decreased arousability. We investigated sleep characteristics in children with refractory nocturnal enuresis. Materials and Methods: Nine girls and 20 boys between 5 and 19 years old (mean +/- SD age 12.1 +/- 2.7) diagnosed with desmopressin dependent (14) and/or resistant (15) nocturnal enuresis and nocturnal polyuria underwent a standardized investigation protocol, including 1 night of polysomnography. Two age groups of 4 boys and 2 girls 5 to 9 years old, and 16 boys and 7 girls 10 to 19 years old were compared to previously defined controls, including 5 boys and 2 girls 5 to 9 years old and 7 boys and 2 girls 10 to 19 years old. Five to 9 and 10 to 19-year-old controls had a mean of 4.2 +/- 1.5 and 3.3 +/- 0.6 periodic limb movements per hour of sleep, respectively. The total number of arousal-awakenings during sleep was 21.6 +/- 8.1 at ages 5 to 9 years and 21.7 +/- 12.8 at ages 10 to 19. Results: All except I patient had greater than 5 periodic limb movements per sleep hour. The younger and older age groups had a mean of 18.6 +/- 5.7 and 18 +/- 7.8 periodic limb movements per sleep hour, respectively. Total arousal-awakenings were also increased at 86.7 +/- 58.1 and 73.8 +/- 34.8, respectively. Statistical differences were calculated with the Mann-Whitney U test in controls vs the study population for periodic limb movements and in the 2 age groups for arousal-awakening (p = 0.003 and <0.001, respectively). Conclusions: Preliminary data indicate a high incidence of periodic limb movements in sleep at night in children with refractory nocturnal enuresis and increased cortical arousability, leading to awakening.