Deep phenotyping of post-infectious myalgic encephalomyelitis/chronic fatigue syndrome.

Post-infectious myalgic encephalomyelitis/chronic fatigue syndrome (PI-ME/CFS) is a disabling disorder, yet the clinical phenotype is poorly defined, the pathophysiology is unknown, and no disease-modifying treatments are available. We used rigorous criteria to recruit PI-ME/CFS participants with matched controls to conduct deep phenotyping. Among the many physical and cognitive complaints, one defining feature of PI-ME/CFS was an alteration of effort preference, rather than physical or central fatigue, due to dysfunction of integrative brain regions potentially associated with central catechol pathway dysregulation, with consequences on autonomic functioning and physical conditioning. Immune profiling suggested chronic antigenic stimulation with increase in naïve and decrease in switched memory B-cells. Alterations in gene expression profiles of peripheral blood mononuclear cells and metabolic pathways were consistent with cellular phenotypic studies and demonstrated differences according to sex. Together these clinical abnormalities and biomarker differences provide unique insight into the underlying pathophysiology of PI-ME/CFS, which may guide future intervention.

Evaluation of Periodic Limb Movements in Sleep and Iron Status in Children With Autism.

OBJECTIVE: Recent data suggest that both disordered sleep and low serum iron occur more frequently in children with autism compared with children with typical development. Iron deficiency has been linked to specific sleep disorders. The goal of the current study was to evaluate periodic limb movements in sleep and iron status in a group of children with autism compared with typically developing children and children with nonautism developmental delay to determine if iron status correlated with polysomnographic measures of latency and continuity and periodic limb movements in sleep. METHODS: A total of 102 children (68 with autism, 18 typically developing, 16 with developmental delay) aged 2 to 7 years underwent a one-night modified polysomnography study and phlebotomy at the National Institutes of Health to measure serum markers of iron status (ferritin, iron, transferrin, percent transferrin saturation). RESULTS: No serum iron marker was associated with periodic limb movements of sleep or any other sleep parameter; this did not differ among the diagnostic groups. No significant differences among groups were observed on serum iron markers or most polysomnogram parameters: periodic limb movements in sleep, periodic limb movements index, wake after sleep onset, or sleep efficiency. Children in the autism group had significantly less total sleep time. Serum ferritin was uniformly low across groups. CONCLUSIONS: This study found no evidence that serum ferritin is associated with polysomnogram measures of latency or sleep continuity or that young children with autism are at increased risk for higher periodic limb movements index compared with typically developing and developmental delay peers.

An open label trial of donepezil for enhancement of rapid eye movement sleep in young children with autism spectrum disorders.

BACKGROUND: Rapid eye movement (REM) sleep is greatest in the developing brain, is driven by acetylcholine, and may represent a protected time for neuroplasticity. Recently published data from our lab observed that children with autism spent significantly less time in this state during a single night recording than did typically developing children and those with developmental delay without autism. The objective of this study was to determine whether or not donepezil can increase the REM % in children with diagnosed autism spectrum disorder (ASD) found to have REM % values of at least two standard deviations below expected for age. METHODS: Five subjects found to have an ASD (ages 2.5-6.9 years) and demonstrated deficits in REM sleep compared with within-lab controls were enrolled in a dose finding study of donepezil. Each subject was examined by polysomnography for REM sleep augmentation after drug administration. RESULTS: REM sleep as a percentage of Total Sleep Time was increased significantly and REM latency was decreased significantly after drug administration in all subjects. No other observed sleep parameter was changed significantly. CONCLUSIONS: Donepezil can increase the amount of time that children with an ASD spend in the REM sleep state. A double-blind, placebo-controlled trial is needed to assess the association between REM sleep augmentation and learning, cognition, and behavior in such children.

Rapid eye movement sleep percentage in children with autism compared with children with developmental delay and typical development.

OBJECTIVE: To compare objective polysomnographic parameters between 3 cohorts: children with autism, typical development, and developmental delay without autism. DESIGN: Overnight polysomnographic recordings were scored for sleep architecture according to American Academy of Sleep Medicine criteria by a board-certified sleep medicine specialist blind to diagnosis for studies collected between July 2006 and September 2009. SETTING: Subjects were evaluated in the pediatric ward in the Clinical Research Center of the National Institutes of Health. PARTICIPANTS: First 60 consecutive children with autism, 15 with typical development, and 13 with developmental delay matched for nonverbal IQ to the autism group, ranging in age from 2 to 13 years, selected without regard to the presence or absence of sleep problem behavior. MAIN OUTCOME MEASURES: Total sleep time, latencies to non-rapid eye movement (REM) and REM sleep, and percentages of total sleep time for stages 1 and 2 sleep, slow-wave sleep, and REM sleep. RESULTS: There were no differences between the typical vs developmental delay groups. Comparison of children with autism vs typical children revealed shorter total sleep time (P = .004), greater slow-wave sleep percentage (P = .001), and much smaller REM sleep percentage (14.5% vs 22.6%; P < .001). Comparison of children with autism vs children with developmental delay revealed shorter total sleep time (P = .001), greater stage 1 sleep percentage (P < .001), greater slow-wave sleep percentage (P < .001), and much less REM sleep percentage (14.5% v 25%; P < .001). CONCLUSION: A relative deficiency of REM sleep may indicate an abnormality in neural organization in young children with autism that is not directly associated with or related to inherent intellectual disability but may serve as a window into understanding core neurotransmitter abnormalities unique to this disorder.