Sleep-Related Breathing Disorders in Young Adults With Prader-Willi Syndrome: A Placebo-Controlled, Crossover GH Trial.

CONTEXT: Sleep-related breathing disorders (SRBD) are common in people with Prader-Willi syndrome (PWS). Young adults with PWS benefit from GH continuation after attaining adult height by maintaining the improved body composition obtained during childhood. There are, no studies about the effects of GH on SRBD in young adults with PWS who were treated with GH during childhood. OBJECTIVE: Investigate the effects of GH vs placebo on SRBD in young adults with PWS who were treated with GH during childhood and had attained adult height. DESIGN: Two-year, randomized, double-blind, placebo-controlled, crossover study in 27 young adults with PWS, stratified for sex and body mass index. SETTING: Dutch PWS Reference Center. INTERVENTION: Crossover intervention with GH (0.67 mg/m2/d) and placebo, both over one year. MAIN OUTCOME MEASURES: Apnea hypopnea index (AHI), obstructive apnea index (OAI), central apnea index (CAI), measured by polysomnography. RESULTS: Compared with placebo, GH did not increase AHI, CAI, or OAI (P > 0.35). The effect of GH vs placebo was neither different between men and women, nor between patients with a deletion or maternal uniparental disomy/imprinting center defect. After two years, there was no difference in AHI, CAI, or OAI compared with baseline (P > 0.18). Two patients (7%) fulfilled the criteria of obstructive sleep apnea regardless of GH or placebo. CONCLUSIONS: GH compared with placebo does not cause a substantial increase in AHI, CAI, or OAI in adults with PWS who were treated with GH during childhood and have attained adult height. Our findings are reassuring and prove that GH can be administered safely.

Respiratory and sleep disorders in female children with atypical Rett syndrome caused by mutations in the CDKL5 gene.

AIM: In female children with drug-resistant seizures and developmental delay from birth, atypical Rett syndrome caused by mutations in the CDKL5 gene should be considered. Several clinical features resemble classic Rett syndrome. Respiratory and sleep abnormalities are frequently present in Rett syndrome, whereas little is known in patients with CDKL5 mutations. METHOD: In four genetically confirmed female patients with CDKL5 mutations (age range 2-15 y), the presence of breathing and sleep abnormalities was evaluated using the validated Sleep Disturbance Scale for Children and polysomnography (PSG). RESULTS: The Sleep Disturbance Scale for Children indicated disorders of initiating and maintaining sleep, daytime somnolence, and sleep breathing disorders. In one patient, PSG showed central apnoeas during sleep: her total apnoea-hypopnoea index (AHI) was 4.9, of which the central AHI was 3.4/h. When awake, central apnoeas were present in two of the four female children (central AHI 28/h and 41/h respectively), all preceded by hyperventilation. PSG showed low rapid eye movement (REM) sleep (9.7-18.3%), frequent awakenings, and low sleep efficiency (range 59-78%). INTERPRETATION: Episodic hyperventilation followed by central apnoeas was present while awake in two of four patients. This may indicate failure of brainstem respiratory centres. In addition, low REM sleep, frequent arousals (not caused by apnoeas/seizures), and low sleep efficiency were present. Similar to Rett syndrome, in patients with CDKL5 mutations PSG seems warranted to evaluate breathing and sleep disturbances.

Cognition and behavior in pre-pubertal children with Prader-Willi syndrome and associations with sleep-related breathing disorders.

Prader-Willi syndrome (PWS) is characterized by hypotonia, hypogonadism, obesity, and short stature. Neurobehavioral abnormalities, cognitive impairment, and sleep-related breathing disorders (SRBD) are common. In the general population associations between neurobehavioral and cognitive abnormalities and SRBD have been found. We investigated cognition, behavior, and SRBD in children with PWS. Thirty-one pre-pubertal PWS children were evaluated (5 with paternal deletion, 14 with maternal disomy, 4 with imprinting-center mutation, and in 8 the defect was not specified). Cognition was assessed by Wechsler scale subtests, and behavior by parent-questionnaires. Polysomnography was performed. Cognition, behavior, and associations with SRBD were evaluated. All cognitive subtests were significantly below O SDS, with the lowest median (interquartile range) scores for the Block design subtest (-2.7 SDS (-3.0 to -0.3)). In 60%, verbal subtests were less affected than performance subtests. Parents reported problem behavior related to "emotions/behavior not adapted to the social situation" and "insensitivity to social information." All children had SRBD, with an Apnea Hypopnea Index of 4.1/hr (2.6-7.9). One performance subtest score was significantly higher in children with better sleep efficiency, and daytime sleepiness was associated with more autistic-like social impairment. In contrast to our expectations, behavior was worse in children with better sleep-related breathing. In pre-pubertal PWS children, cognition is impaired. Neurobehavioral abnormalities are common, particularly autistic-like social impairment. Sleep efficiency was associated with better performance on one of the performance subtests, and neurobehavioral abnormalities were associated with daytime sleepiness. In contrast, we could not confirm a positive association of neurobehavioral abnormalities with SRBD in PWS.

Psychomotor development in infants with Prader-Willi syndrome and associations with sleep-related breathing disorders.

Prader-Willi syndrome (PWS) is a neurogenetic disorder with hypotonia, psychomotor delay, obesity, short stature, and sleep-related breathing disorders. The aim of this study was to evaluate the association between psychomotor development and sleep-related breathing disorders in PWS infants. Bayley Scales of Infant Development were performed in 22 PWS infants, with a median (interquartile range, IQR) age of 1.8 (1.1-3.4) y, and a body mass index SD score (BMISDS) of -0.5 (-1.3 to 1.6). We evaluated psychomotor development in relation to results of polysomnography. Median (IQR) mental and motor development was 73.1% (64.3-79.6%) and 55.2% (46.5-63.1%) of normal children, respectively. All infants had sleep-related breathing disorders, mostly of central origin. The apnea hypopnea index was not associated with psychomotor development. Only four infants had obstructive sleep apnea syndrome (OSAS). They had a significantly delayed mental development of 65.5% (60.0-70.3%) of normal. They had a median BMISDS of 1.4 (0.1-1.6), which tended to be higher than in those without OSAS. Our data indicate that psychomotor development in PWS infants is not related to central sleep-related breathing disorders, but infants with OSAS have more severely delayed mental development, suggesting that PWS infants should be screened for OSAS.

The development of sleep during the first months of life.

The development of sleep during the first months of life is intriguing from a scientific point of view but is interesting to the clinician as well. This review aims at providing data on sleep in "low-risk" premature neonates, neonates born at term, and infants up to the age of 6 months. The various milestones in clinical and polygraphic features of sleep allow for week-to-week assessment of brain function in normal and sick children.