Service evaluation suggests variation in clinical care provision in adults with congenital adrenal hyperplasia in the UK and Ireland.

BACKGROUND: Congenital adrenal hyperplasia (CAH) encompasses a rare group of autosomal recessive disorders, characterised by enzymatic defects in steroidogenesis. Heterogeneity in management practices has been observed internationally. The International Congenital Adrenal Hyperplasia registry (I-CAH, https://sdmregistries.org/) was established to enable insights into CAH management and outcomes, yet its global adoption by endocrine centres remains unclear. DESIGN: We sought (1) to assess current practices amongst clinicians managing patients with CAH in the United Kingdom and Ireland, with a focus on choice of glucocorticoid, monitoring practices and screening for associated co-morbidities, and (2) to assess use of the I-CAH registry. MEASUREMENTS: We designed and distributed an anonymised online survey disseminated to members of the Society for Endocrinology and Irish Endocrine Society to capture management practices in the care of patients with CAH. RESULTS: Marked variability was found in CAH management, with differences between general endocrinology and subspecialist settings, particularly in glucocorticoid use, biochemical monitoring and comorbidity screening, with significant disparities in reproductive health monitoring, notably in testicular adrenal rest tumours (TARTs) screening (p = .002), sperm banking (p = .0004) and partner testing for CAH (p < .0001). Adoption of the I-CAH registry was universally low. CONCLUSIONS: Differences in current management of CAH continue to exist. It appears crucial to objectify if different approaches result in different long-term outcomes. New studies such as CaHASE2, incorporating standardised minimum datasets including replacement therapies and monitoring strategies as well as longitudinal data collection, are now needed to define best-practice and standardise care.

Acute sleep deprivation: the effects of the AMPAKINE compound CX717 on human cognitive performance, alertness and recovery sleep.

AMPA receptor modulation is a potential novel approach to enhance cognitive performance. CX717 is a positive allosteric modulator of the AMPA receptor that has shown efficacy in rodent and primate cognition models. CX717 (100 mg, 300 mg and 1000 mg) and placebo were studied in 16 healthy male volunteers (18-45 years) in a randomized, crossover study. Cognitive function, arousal and recovery sleep (by polysomnography) were assessed during the extended wakefulness protocol. Placebo condition was associated with significant decrements in cognition, particularly at the circadian nadir (between 03:00 and 05:00). Pre-specified primary and secondary analyses (general linear mixed modelling, GLMM) at each separate time point did not reveal consistent improvements in performance or objective alertness with any dose of CX717. Exploratory repeated measures analysis, a method used to take into account the influence of individual differences, demonstrated an improvement in attention-based task performance following the 1000 mg dose. Analysis of the recovery sleep showed that CX717 1000 mg significantly reduced stage 4 and slow-wave sleep (p ≤ 0.05) with evidence of reduced electroencephalogram (EEG) slow-wave and spindle activity. The study suggests that CX717 only at the 1000 mg dose may counteract effects of sleep deprivation on attention-based tasks and that it may interfere with subsequent recovery sleep.

Effect of a novel histamine subtype-3 receptor inverse agonist and modafinil on EEG power spectra during sleep deprivation and recovery sleep in male volunteers.

RATIONALE: Histamine and dopamine contribute to the maintenance of wakefulness. OBJECTIVE: This study aims to conduct an exploratory analysis of the effects of 10 and 50 mg of MK-0249, a novel histamine subtype-3 receptor inverse agonist, and 200 mg of modafinil, a presumed dopaminergic compound, on EEG power spectra during sleep deprivation and subsequent recovery sleep. METHODS: A total of 25 healthy men were recruited to a double-blind, placebo-controlled cross-over design. EEG power spectra, an electrophysiological marker of changes in sleepiness and vigilance, were obtained at the beginning of wake maintenance tests at two-hourly intervals throughout a night and day of sleep deprivation, which is an established model of excessive sleepiness. RESULTS: After placebo, sleep deprivation was associated with enhancements in delta and theta and reductions in alpha and beta activity. Following dosing at 02:00 h, MK-0249 and modafinil reduced delta and theta activity and enhanced alpha and beta activity, compared to placebo. During recovery sleep initiated at 21:00 h, latency to sleep onset and number of awakenings were not different from placebo for any of the active treatments. Wake after sleep onset and stage 1% was increased and total sleep time, SWS% and REM% were reduced after both doses of MK-0249. Compared to placebo, MK-0249, the 50-mg dose in particular, reduced activity in some delta and theta/alpha frequencies and enhanced beta activity during NREM sleep and REM sleep. After modafinil, no changes were observed for power spectra during sleep. CONCLUSION: Both MK-0249 and modafinil exert effects on the EEG which are consistent with wake promotion.

PER3 polymorphism and cardiac autonomic control: effects of sleep debt and circadian phase.

A variable number tandem repeat polymorphism in the coding region of the circadian clock PERIOD3 (PER3) gene has been shown to affect sleep. Because circadian rhythms and sleep are known to modulate sympathovagal balance, we investigated whether homozygosity for this PER3 polymorphism is associated with changes in autonomic nervous system (ANS) activity during sleep and wakefulness at baseline and after sleep deprivation. Twenty-two healthy participants were selected according to their PER3 genotype. ANS activity, evaluated by heart rate (HR) and HR variability (HRV) indexes, was quantified during baseline sleep, a 40-h period of wakefulness, and recovery sleep. Sleep deprivation induced an increase in slow-wave sleep (SWS), a decrease in the global variability, and an unbalance of the ANS with a loss of parasympathetic predominance and an increase in sympathetic activity. Individuals homozygous for the longer allele (PER3(5/5)) had more SWS, an elevated sympathetic predominance, and a reduction of parasympathetic activity compared with PER3(4/4), in particular during baseline sleep. The effects of genotype were strongest during non-rapid eye movement (NREM) sleep and absent or much smaller during REM sleep. The NREM-REM cycle-dependent modulation of the low frequency-to-(low frequency + high frequency) ratio was diminished in PER3(5/5) individuals. Circadian phase modulated HR and HRV, but no interaction with genotype was observed. In conclusion, the PER3 polymorphism affects the sympathovagal balance in cardiac control in NREM sleep similar to the effect of sleep deprivation.

Blue-enriched white light in the workplace improves self-reported alertness, performance and sleep quality.

OBJECTIVES: Specifications and standards for lighting installations in occupational settings are based on the spectral sensitivity of the classical visual system and do not take into account the recently discovered melanopsin-based, blue-light-sensitive photoreceptive system. The authors investigated the effects of exposure to blue-enriched white light during daytime workhours in an office setting. METHODS: The experiment was conducted on 104 white-collar workers on two office floors. After baseline assessments under existing lighting conditions, every participant was exposed to two new lighting conditions, each lasting 4 weeks. One consisted of blue-enriched white light (17 000 K) and the other of white light (4000 K). The order was balanced between the floors. Questionnaire and rating scales were used to assess alertness, mood, sleep quality, performance, mental effort, headache and eye strain, and mood throughout the 8-week intervention. RESULTS: Altogether 94 participants [mean age 36.4 (SD 10.2) years] were included in the analysis. Compared with white light (4000 K), blue-enriched white light (17 000 K) improved the subjective measures of alertness (P<0.0001), positive mood (P=0.0001), performance (P<0.0001), evening fatigue (P=0.0001), irritability (P=0.004), concentration (P<0.0001), and eye discomfort (P=0.002). Daytime sleepiness was reduced (P=0.0001), and the quality of subjective nocturnal sleep (P=0.016) was improved under blue-enriched white light. When the participants' expectation about the effect of the light treatments was entered into the analysis as a covariate, significant effects persisted for performance, alertness, evening fatigue, irritability, difficulty focusing, concentrating, and blurred vision. CONCLUSIONS: Exposure to blue-enriched white light during daytime workhours improves subjective alertness, performance, and evening fatigue.

PER3 polymorphism predicts sleep structure and waking performance.

Circadian rhythmicity and sleep homeostasis interact to regulate sleep-wake cycles [1-4], but the genetic basis of individual differences in sleep-wake regulation remains largely unknown [5]. PERIOD genes are thought to contribute to individual differences in sleep timing by affecting circadian rhythmicity [6], but not sleep homeostasis [7, 8]. We quantified the contribution of a variable-number tandem-repeat polymorphism in the coding region of the circadian clock gene PERIOD3 (PER3) [9, 10] to sleep-wake regulation in a prospective study, in which 24 healthy participants were selected only on the basis of their PER3 genotype. Homozygosity for the longer allele (PER3(5/5)) had a considerable effect on sleep structure, including several markers of sleep homeostasis: slow-wave sleep (SWS) and electroencephalogram (EEG) slow-wave activity in non-rapid eye movement (non-REM) sleep and theta and alpha activity during wakefulness and REM sleep were all increased in PER3(5/5) compared to PER3(4/4) individuals. In addition, the decrement of cognitive performance in response to sleep loss was significantly greater in the PER3(5/5) individuals. By contrast, the circadian rhythms of melatonin, cortisol, and peripheral PER3 mRNA expression were not affected. The data show that this polymorphism in PER3 predicts individual differences in the sleep-loss-induced decrement in performance and that this differential susceptibility may be mediated by its effects on sleep homeostasis.

Serotonergic antidepressants are associated with REM sleep without atonia.

STUDY OBJECTIVES: Rapid eye movement (REM) sleep behavior disorder (RBD) is generally observed in older men and in individuals with specific neurologic diseases. There are case reports of RBD in individuals taking serotonergic antidepressants. Our objective was to assess electromyogram (EMG) activity during REM sleep in individuals taking serotonergic antidepressants and in a matched control group not on such medication. DESIGN: Chart review of clinical and polysomnographic data. SETTING: Sleep laboratory affiliated with a general hospital. PARTICIPANTS: 15 subjects taking a serotonergic antidepressant and 15 age-matched individuals not on such medication. MEASUREMENTS: Submental and anterior tibialis tonic and phasic EMG activity during REM sleep, REM latency, time in REM, apnea-hypopnea index, periodic leg movements of sleep index, and sleep-architecture measures. RESULTS: Tonic, but not phasic, submental EMG activity during REM sleep was significantly more common in the antidepressant-treated group than in the control group (P < .02). Tonic REM submental EMG activity correlated with REM latency (r = .42, P = .02) and inversely with REM time (r = -.36, P = .05). Subject age correlated with tonic REM submental EMG activity (r = .58, P = .02) in the antidepressant group There were also trends for more phasic activity in the anterior tibialis (P = .09) and submental (P = .07) EMG in REM sleep in the antidepressant group than in the control group. CONCLUSIONS: Subjects taking serotonergic antidepressants had more EMG activity in the submental lead during REM sleep than did controls. This correlated with measures of REM suppression and age. Individuals taking such medications may be at increased risk of developing REM sleep behavior disorder, particularly with increasing age.