Association between depressive symptoms and sleep neurophysiology in early adolescence

Prevalence and lifestyle determinants of depressive symptoms among Chinese children and adolescents

Based on Chinese Students' Fitness Health Examination, this study sought to investigate the relationships between depressive symptoms and family environment, physical activity, dietary habits, sleep and sedentary behavior among children and adolescents. A cross-sectional study was carried out to estimate the prevalence of depressive symptoms in 32,389 participants (grades 4-12) using the CES-D. Logistic regression was used to evaluate the relationships between lifestyle determinants and depressive symptoms, and a random forest model was used to rank the importance of those determinants. The overall prevalence of depressive symptoms was 39.93%. Students with depressive symptoms had higher grades, lower parental educational levels and unhealthy lifestyles (P < 0.05). The top ten most important determinants of depressive symptoms were grade, egg intake, milk/soy product intake, frequency of muscle strength training, screen time, sleep duration, parental educational level, sugar beverage intake and total physical activity. Socioeconomic status, physical activity, sleep and screen time, and diet habits are determinants of depressive symptoms, and surveillance of lifestyles may be an effective way to detect students with depressive symptoms early.

The effect of slow wave sleep deprivation on mood in adolescents with depressive symptoms: A pilot study

BACKGROUND

There is an urgent need for safe, rapid-acting treatment strategies for adolescent depression. In depressed adults, slow wave sleep deprivation (SWSD) improved next-day mood without disrupting sleep duration, but SWSD has not been tested in adolescents. In a pilot study, the aim was to assess the effect of SWSD on sleep physiology and mood outcomes (depression, rumination, anhedonia) among adolescents with depressive symptoms.

METHODS

Sixteen adolescents (17.44 ± 1.46 yr, 12 female) completed three nights of polysomnographic sleep recording: Baseline, SWSD, and Recovery nights. Acoustic stimulation (tones of random pitch, duration, and volume) suppressed slow wave sleep (SWS) in real-time during SWSD. After each night, depression, rumination, and anhedonia severity were assessed.

RESULTS

SWSD successfully suppressed SWS, increased N2, and had minimal impact on Rapid Eye Movement (REM), nocturnal awakenings, and total sleep time. While SWSD did not improve depression or anhedonia severity overall, lower baseline non-REM alpha activity and greater SWS rebound during recovery sleep correlated with SWSD-related reduction in clinician-rated depression severity. Next-day rumination severity decreased after SWSD, with sustained improvements following recovery sleep. However, rumination improvement was not associated with SWS suppression, but rather reduction in total sleep time and REM in exploratory correlation models.

LIMITATIONS

Small sample size and large proportion of females.

CONCLUSION

SWSD did not improve depression in adolescents overall but a subset with low non-REM alpha activity and intact homeostatic sleep regulation may benefit from this approach. Findings from this pilot study also suggest that partial sleep deprivation may be a beneficial therapeutic strategy for rumination in adolescents.

Suvorexant alters dynamics of the sleep-electroencephalography-power spectrum and depressive-symptom trajectories during inpatient opioid withdrawal

STUDY OBJECTIVES

Opioid withdrawal is an aversive experience that often exacerbates depressive symptoms and poor sleep. The aims of the present study were to examine the effects of suvorexant on oscillatory sleep-electroencephalography (EEG) band power during medically managed opioid withdrawal, and to examine their association with withdrawal severity and depressive symptoms.

METHODS

Participants with opioid use disorder (N = 38: age-range:21-63, 87% male, 45% white) underwent an 11-day buprenorphine taper, in which they were randomly assigned to suvorexant (20 mg [n = 14] or 40 mg [n = 12]), or placebo [n = 12], while ambulatory sleep-EEG data was collected. Linear mixed-effect models were used to explore: (1) main and interactive effects of drug group, and time on sleep-EEG band power, and (2) associations between sleep-EEG band power change, depressive symptoms, and withdrawal severity.

RESULTS

Oscillatory spectral power tended to be greater in the suvorexant groups. Over the course of the study, decreases in delta power were observed in all study groups (β = -189.082, d = -0.522, p = <0.005), increases in beta power (20 mg: β = 2.579, d = 0.413, p = 0.009 | 40 mg β = 5.265, d = 0.847, p < 0.001) alpha power (20 mg: β = 158.304, d = 0.397, p = 0.009 | 40 mg: β = 250.212, d = 0.601, p = 0.001) and sigma power (20 mg: β = 48.97, d = 0.410, p < 0.001 | 40 mg: β = 71.54, d = 0.568, p < 0.001) were observed in the two suvorexant groups. During the four-night taper, decreases in delta power were associated with decreases in depressive symptoms (20 mg: β = 190.90, d = 0.308, p = 0.99 | 40 mg: β = 433.33, d = 0.889 p = <0.001), and withdrawal severity (20 mg: β = 215.55, d = 0.034, p = 0.006 | 40 mg: β = 192.64, d = -0.854, p = <0.001), in both suvorexant groups and increases in sigma power were associated with decreases in withdrawal severity (20 mg: β = -357.84, d = -0.659, p = 0.004 | 40 mg: β = -906.35, d = -1.053, p = <0.001). Post-taper decreases in delta (20 mg: β = 740.58, d = 0.964 p = <0.001 | 40 mg: β = 662.23, d = 0.882, p = <0.001) and sigma power (20 mg only: β = 335.54, d = 0.560, p = 0.023) were associated with reduced depressive symptoms in the placebo group.

CONCLUSIONS

Results highlight a complex and nuanced relationship between sleep-EEG power and symptoms of depression and withdrawal. Changes in delta power may represent a mechanism influencing depressive symptoms and withdrawal.

Sleep spindles in adolescents with major depressive disorder

Sleep spindle differences in adolescents with major depressive disorder (MDD) compared to healthy adolescents is an ongoing debate. Results mostly indicate decreased sleep spindle activity in adolescents with MDD. Given that sleep spindles predominate NREM and that acutely delaying the sleep period via a "sleep delay challenge" (SDC) increases non-rapid eye movement (NREM) sleep duration, it may be possible to increase spindle density in adolescents with MDD, which may provide a therapeutic benefit to depression symptoms. Here, we examined the impact of a SDC on spindle density and depression symptomology in adolescents with MDD (n = 66) and healthy controls (n = 62) tested across three nights: adaptation, normal sleep, and a SDC night which delayed bedtime by three hours. The results showed that; (1) there was no difference in spindle density between groups on the normal sleep night, (2) following the SDC, both males and females with MDD had a decrease in the frequency of slow spindles, while only females with MDD had an increase in the frequency of fast spindles, (3) acute SDC reduced depression symptoms in both groups, and (4) light sleep on the normal sleep night and slow spindle frequency at SDC predicted an 8 % improvement in depression symptoms, regardless of sex or MDD diagnosis. Taken together, these results suggest that; (a) spindles may be a useful biological marker of depression symptomatology regardless of clinical MDD diagnosis, and (b) that acute SDC may help alleviate depression symptoms in adolescents with MDD.

Emotional memories are enhanced when reactivated in slow wave sleep, but impaired when reactivated in REM

Sleep supports memory consolidation. However, it is not completely clear how different sleep stages contribute to this process. While rapid eye movement sleep (REM) has been traditionally implicated in the processing of emotionally charged material, recent studies indicate a role for slow wave sleep (SWS) in strengthening the memories of emotional stimuli. Here, to directly examine which sleep stage is primarily involved in emotional memory consolidation, we used targeted memory reactivation (TMR) in REM and SWS during a daytime nap. We also examined neural oscillations associated with TMR-related changes in memory. Contrary to our hypothesis, reactivation of emotional stimuli during REM led to impaired memory. Meanwhile, reactivation of emotional stimuli in SWS improved memory and was strongly correlated with the product of times spent in REM and SWS (%SWS Ã- %REM). When this variable was taken into account, reactivation significantly enhanced memory, with larger reactivation benefits compared to reactivation in REM. Notably, sleep spindle activity was modulated by emotional valence, and delta/theta activity was correlated with the memory benefit for both emotional and neutral items. Finally, we found no evidence that emotional memories benefited from TMR more than did neutral ones. Our results provide direct evidence for a complementary role of both REM and SWS in emotional memory consolidation, and suggest that REM may separately facilitate forgetting. In addition, our findings expand upon recent evidence indicating a link between sleep spindles and emotional processing.

Sleep to Internalizing Pathway in Young Adolescents (SIPYA): A proposed neurodevelopmental model

The prevalence of internalizing disorders, i.e., anxiety and depressive disorders, spikes in adolescence and has been increasing amongst adolescents despite the existence of evidence-based treatments, highlighting the need for advancing theories on how internalizing disorders emerge. The current review presents a theoretical model, called the Sleep to Internalizing Pathway in Young Adolescents (SIPYA) Model, to explain how risk factors, namely sleep-related problems (SRPs), are prospectively associated with internalizing disorders in adolescence. Specifically, SRPs during late childhood and early adolescence, around the initiation of pubertal development, contribute to the interruption of intrinsic brain networks dynamics, both within the default mode network and between the default mode network and other networks in the brain. This interruption leaves adolescents vulnerable to repetitive negative thought, such as worry or rumination, which then increases vulnerability to internalizing symptoms and disorders later in adolescence. Sleep-related behaviors are observable, modifiable, low-stigma, and beneficial beyond treating internalizing psychopathology, highlighting the intervention potential associated with understanding the neurodevelopmental impact of SRPs around the transition to adolescence. This review details support for the SIPYA Model, as well as gaps in the literature and future directions.

Sleep and physical activity: results from a long-term actigraphy study in adolescents

PURPOSE

Research to date suggests that physical activity is associated with improved sleep, but studies have predominantly relied on self-report measures and have not accounted for school day/free day variability. To address these gaps in the literature, the aim of the present study was to (a) quantify physical activity in adolescents using long-term daily actigraphy measurement and (b) to examine the association between actigraphically assessed steps and sleep behavior in a sample of healthy adolescents. To be able to capture intra- and inter-individual differences in the daily physical activity of adolescents, we examined within as well as between subjects effects and its association with sleep.

METHODS

Fifty adolescents between 10 and 14 years of age were included in the present study. In total 5989 days of actigraphy measurement (average of 119 ± 40 days per participant; range = 39-195 days) were analyzed. We use multilevel modeling to disentangle the within and between subject effects of physical activity on sleep. In this way, we examine within an individual, the association between steps during the day and subsequent sleep on a day-to-day basis. On the other hand, our between subjects' analysis allows us to ascertain whether individuals with more overall physical activity have better sleep.

RESULTS

Within a subject more steps on school and free days were associated with later bed times on school and free days as well as later rise times on school days only. On the other hand, comparing between subjects' effects, more steps were associated with lower sleep efficiency on free and school days. No other significant associations were found for the other sleep variables.

CONCLUSION

Our results obtained through objective and long-term measurement of both sleep and number of steps suggest weak or non-significant associations between these measures for most sleep variables. We emphasize the importance of the methodology and the separation of within subject from between subject features when examining the relationship between physical activity and sleep.

Handling missing data in rest-activity time series measured by actimetry

A handling procedure of off-wrist episodes in actimetry time series of motor activity is presented using two records (regular vs. irregular sleep-wake cycle and daytime activity) of 14 consecutive days sampled in 1-minute epochs. We generated single missing value (NA) intervals of 1 h, 2 h, 4 h, 6 h, 12 h, and 24 h as well as random NA episodes following probabilistic rules to simulate real-life off-wrist episodes. Then, we replaced these episodes with "zeroes" (i.e., the default of immobility records), mean or median of the remaining 13 days corresponding to the missing bins. Single missing episodes of up to 12 h resulted in less than 5% variation from the original values. The irregular series showed higher variability in acrophase, MESOR, L5, M10 and RA compared to the regular series. Random missing allocation simulating real-life off-wrist episodes resulted in significant changes in most parameters, and the imputation of zeroes significantly increased the variance; however, replacing NA with mean or median resulted in patterns similar to those of NA. We recommend replacing 'zeroes' with NA whenever possible, given the risk of inflating invariance using zeroes. If the parameters cannot be computed in the presence of NA, we recommend using the weekly mean of corresponding timepoints.

Association of a novel EEG metric of sleep depth/intensity with attention-deficit/hyperactivity, learning, and internalizing disorders and their pharmacotherapy in adolescence

STUDY OBJECTIVES

Psychiatric/learning disorders are associated with sleep disturbances, including those arising from abnormal cortical activity. The odds ratio product (ORP) is a standardized electroencephalogram metric of sleep depth/intensity validated in adults, while ORP data in youth are lacking. We tested ORP as a measure of sleep depth/intensity in adolescents with and without psychiatric/learning disorders.

METHODS

Four hundred eighteen adolescents (median 16 years) underwent a 9-hour, in-lab polysomnography. Of them, 263 were typically developing (TD), 89 were unmedicated, and 66 were medicated for disorders including attention-deficit/hyperactivity (ADHD), learning (LD), and internalizing (ID). Central ORP during non-rapid eye movement (NREM) sleep was the primary outcome. Secondary/exploratory outcomes included central and frontal ORP during NREM stages, in the 9-seconds following arousals (ORP-9), in the first and second halves of the night, during REM sleep and wakefulness.

RESULTS

Unmedicated youth with ADHD/LD had greater central ORP than TD during stage 3 and in central and frontal regions during stage 2 and the second half of the sleep period, while ORP in youth with ADHD/LD on stimulants did not significantly differ from TD. Unmedicated youth with ID did not significantly differ from TD in ORP, while youth with ID on antidepressants had greater central and frontal ORP than TD during NREM and REM sleep, and higher ORP-9.

CONCLUSIONS

The greater ORP in unmedicated youth with ADHD/LD, and normalized levels in those on stimulants, suggests ORP is a useful metric of decreased NREM sleep depth/intensity in ADHD/LD. Antidepressants are associated with greater ORP/ORP-9, suggesting these medications induce cortical arousability.

Sleep quality and neurohormonal and psychophysiological accompanying factors in adolescents with depressive disorders: study protocol

BACKGROUND

Depressive disorders are common mental health problems during adolescence. Many adolescents with depression describe difficulties with sleeping. Findings of previous studies regarding changes in objective sleep quality in adolescents with depressive disorders are heterogeneous.

AIMS

This study aims to investigate differences in objective and subjective sleep quality between adolescents with depressive disorders and healthy peers, and to evaluate if potential changes in sleep occur concurrently with changes in the release of cortisol and alpha-amylase after awakening.

METHOD

This non-interventional parallel study examines correlations between depressive disorders, sleep quality and release of stress hormones. Sleep quality in the past 2 weeks, severity of depressive symptoms, psychiatric comorbidities and stress response of 30 adolescents with depressive disorders and 30 healthy controls (N = 60) are assessed via questionnaires. In participants' home environments, the objective sleep quality of seven consecutive nights is measured by sleep accelerometry. After awakening, participants answer sleep questionnaires to examine the subjective sleep quality of those nights. Furthermore, salivary cortisol and alpha-amylase are measured three times after awakening (+0 min, +30 min and +45 min after awakening).

CONCLUSIONS

Sleep is an important factor for prognosis and well-being in adolescents with depression. The results of this study can be highly valuable to integrate a more detailed examination of sleep quality and sleeping impairments in the treatment of adolescent depressive disorders.

Movement behaviors and their association with depressive symptoms in Brazilian adolescents: A cross-sectional study

BACKGROUND

Physical activity, sleep, and sedentary behaviors compose 24-h movement behaviors and have been independently associated with depressive symptoms. However, it is not clear whether it is the movement behavior itself or other contextual factors that are related to depressive symptoms. The objective of the present study was to examine the associations between self-reported and accelerometer-measured movement behaviors and depressive symptoms in adolescents.

METHODS

Cross-sectional data from 610 adolescents (14-18 years old) were used. Adolescents answered questions from the Center for Epidemiological Studies Depression scale and reported time spent watching videos, playing videogames, using social media, time spent in various physical activities, and daytime sleepiness. Wrist-worn accelerometers were used to measure sleep duration, sleep efficiency, sedentary time, and physical activity. Mixed-effects logistic regressions were used.

RESULTS

Almost half of the adolescents (48%) were classified as being at high risk for depression (score ≥20). No significant associations were found between depressive symptoms and accelerometer-measured movement behaviors, self-reported non-sport physical activity, watching videos, and playing videogames. However, higher levels of self-reported total physical activity (odd ratio (OR) = 0.92, 95% confidence interval (95%CI): 0.86-0.98) and volume of sports (OR = 0.88, 95%CI: 0.79-0.97), in minutes, were associated with a lower risk of depression, while using social media for either 2.0-3.9 h/day (OR = 1.77, 95%CI: 1.58-2.70) or >3.9 h/day (OR = 1.67, 95%CI: 1.10-2.54), as well as higher levels of daytime sleepiness (OR = 1.17, 95%CI: 1.12-1.22), were associated with a higher risk of depression.

CONCLUSION

What adolescents do when they are active or sedentary may be more important than the time spent in the movement behaviors because it relates to depressive symptoms. Targeting daytime sleepiness, promoting sports, and limiting social media use may benefit adolescents.

Understanding Sleep-Wake Behavior in Late Chronotype Adolescents: The Role of Circadian Phase, Sleep Timing, and Sleep Propensity

BACKGROUND

Adolescents with a late chronotype are at greater risk for mood disorders, risk-taking behaviors, school absenteeism, and lower academic achievement. As there are multiple causes for late chronotype, the field lacks studies on the relationship between mood, circadian phase, and phase angle of entrainment in late chronotype adolescents. Three objectives guide this explorative study: (1) to describe sleep, circadian phase, and phase angle of entrainment in late chronotype adolescents, (2) to explore how different levels of lateness are associated with sleep quality, sleep propensity, and mood, and (3) to investigate the influence of circadian phase on bedtime choice and sleep duration.

METHODS

Baseline data from 19 male adolescents (M = 16.4 ± 1.0 yrs), who were part of a larger intervention trial, were analyzed. Chronotype was measured with the Munich Chronotype Questionnaire, circadian timing via dim light melatonin onset (DLMO), and sleep habits with a 7-day sleep log. Further questionnaires assessed daytime sleepiness, sleep quality, and mood. Evening sleepiness and sustained attention were used as a proxy for evening sleep propensity.

RESULTS

On school nights, sleep duration averaged 7.78 h (±1.65), and 9.00 h (±1.42) on weekend nights. Mean DLMO was observed at 23.13 h (± 1.65), with a weekend phase angle of entrainment of 2.48 h. Regression fittings revealed a tendency for shorter phase angles with delayed DLMOs. Further analysis with chronotype subgroups revealed that this was only true for light and moderate late types, whereas extreme late types showed wide phase angles. Even though daytime sleepiness and sleep duration did not differ between subgroups, mood and sleep quality declined as lateness increased. Extreme late chronotypes experienced higher evening sleepiness, while slight late chronotypes showed higher evening attention. Chronotype but not DLMO predicted bedtime on school- and particularly weekend-nights.

CONCLUSIONS

Our findings suggest that with increasing lateness, the likelihood of experiencing poor sleep quality and mood disorders increases. As DLMO did not predict bedtime, our data indicate that the factors contributing to a late chronotype are versatile and complex, particularly for extreme late types. Further studies involving a larger and gender-balanced sample are needed to confirm findings.

Spindle-related brain activation in patients with insomnia disorder: An EEG-fMRI study

Sleep spindles have been implicated in sleep protection, depression and anxiety. However, spindle-related brain imaging mechanism underpinning the deficient sleep protection and emotional regulation in insomnia disorder (ID) remains elusive. The aim of the current study is to investigate the relationship between spindle-related brain activations and sleep quality, symptoms of depression and anxiety in patients with ID. Participants (n = 46, 28 females, 18-60 years) were recruited through advertisements including 16 with ID, according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, and 30 matched controls. Group differences in spindle-related brain activations were analyzed using multimodality data acquired with simultaneous electroencephalography and functional magnetic resonance imaging during sleep. Compared with controls, patients with ID showed significantly decreased bilateral spindle-related brain activations in the cingulate gyrus (familywise error corrected p ˂ 0.05, cluster size 4401 mm³). Activations in the cingulate gyrus were negatively correlated with Pittsburgh Sleep Quality Index scores (r = -0.404, p = 0.005) and Self-Rating Anxiety Scale scores (r = -0.364, p = 0.013), in the pooled sample. These findings underscore the key role of spindle-related brain activations in the cingulate gyrus in subjective sleep quality and emotional regulation in ID.

School schedule affects sleep, but not physical activity, screen time and diet behaviors

BACKGROUND

Behavioral changes during adolescence are affected by biological and social aspects. However, environment aspects, which are beyond adolescents' control, also contribute to behavior adoption, and school may have a significant impact in these behaviors. This cross-sectional study aims to investigate how lifestyle behaviors are associated with the school shift attended by high school students.

METHODS

The sample comprised 635 high school students (51.2% girls, 16.33 ± 1.0 years old) from Southern Brazil. Physical activities of different intensities (light and moderate-to-vigorous), sedentary behaviors, and sleep (duration, efficiency, and timing) were measured using accelerometers. Engagement in sport and non-sport activities, screen time indicators, and diet were self-reported. Linear models were fitted to compare each lifestyle behavior between the two school shifts.

RESULTS

Students attending the afternoon shift slept (β = 01:29 95%CI 01:13; 01:46) and woke up later (β = 01.41 95%CI 01:27; 01:54), and had a longer sleep duration (β = 00:12 95%CI 0:02; 00:21) than those attending the morning shift. However, the sleep efficiency of those in the afternoon shift was lower than their peers in the morning shift (β = -1.89 95%CI -3.01; -0.77).

CONCLUSIONS

School schedule was associated with sleep behaviors of adolescents, but not with other lifestyle behaviors.

Association of Depressive Symptoms with Sleep Disturbance: A Co-twin Control Study

BACKGROUND

Few studies have comprehensively evaluated the association of depression with sleep disturbance using a controlled twin study design.

PURPOSE

To cross-sectionally evaluate the association of depression with both objective and subjective sleep disturbance.

METHODS

We studied 246 members of the Vietnam Era Twin Registry. We measured depressive symptoms using the Beck Depression Inventory-II (BDI) and assessed major depression using structured clinical interviews. Twins underwent one-night polysomnography and 7-day actigraphy to derive measures of objective sleep and completed the Pittsburgh Sleep Quality Index for subjective sleep. Multivariable mixed-effects models were used to examine the association.

RESULTS

Twins were all male, mostly white (97%), with a mean (SD) age of 68 (2). The mean (SD) BDI was 5.9 (6.3), and 49 (20%) met the criteria for major depression. For polysomnography, each 5-unit higher BDI, within-pair, was significantly associated with 19.7 min longer rapid eye movement (REM) sleep latency, and 1.1% shorter REM sleep after multivariable adjustment. BDI was not associated with sleep architecture or sleep-disordered breathing. For actigraphy, a higher BDI, within-pair, was significantly associated with lower sleep efficiency, more fragmentation and higher variability in sleep duration. BDI was associated with almost all dimensions of self-reported sleep disturbance. Results did not differ by zygosity, and remained consistent using major depression instead of BDI and were independent of the presence of comorbid posttraumatic stress disorder and antidepressant use.

CONCLUSIONS

Depression is associated with REM sleep disruption in lab and sleep fragmentation and sleep variability at home, but not with sleep architecture or sleep-disordered breathing.

The relation between sigma power and internalizing problems across development

Internalizing problems are characterized by deficits in emotion processing and regulation. They are among the most common problems in children and adolescents and mark an increased risk for depressive and anxiety disorders in later life. First evidence suggests that sleep alterations are related to the development and/or persistence of mood and anxiety disorders in children, adolescents, and adults. Most recently, data from clinical samples showed that brain activity in the sigma frequency band (9-16 Hz, i.e. sleep spindle frequency) is associated with internalizing problems in children and adolescents. However, less is known about the association between sigma power and internalizing problems in healthy participants within this age group. Here, we re-analyzed longitudinal data (25 healthy subjects (18 females) at two time points (T1: childhood mean age: 9.52 ± 0.77; T2: adolescence mean age: 16.08 ± 0.91) by correlating sigma power with measures for internalizing problems. Moreover, we calculated sigma power ratios (frontal/central, frontal/parietal, frontal/occipital) to examine whether these measures would reflect developmental changes more accurately. We found that higher values of internalizing problems at T1 were related to a lower decrease in sigma power from T1 to T2 at frontal and central derivations. Furthermore, higher values of internalizing problems at T1 as well as at T2 were related to higher sigma power ratios at T2. We suggest that sigma power may reflect maturational processes (e.g. network efficiency, integrity) related to the development of internalizing problems. In particular, a stronger decrease in frontal sigma power from childhood to adolescence may indicate a healthier development. Thus, our results emphasize the role of sigma power as a useful marker for internalizing problems during adolescence.

The Effects of Daytime Psilocybin Administration on Sleep: Implications for Antidepressant Action

Serotonergic agonist psilocybin is a psychedelic with antidepressant potential. Sleep may interact with psilocybin’s antidepressant properties like other antidepressant drugs via induction of neuroplasticity. The main aim of the study was to evaluate the effect of psilocybin on sleep architecture on the night after psilocybin administration. Regarding the potential antidepressant properties, we hypothesized that psilocybin, similar to other classical antidepressants, would reduce rapid eye movement (REM) sleep and prolong REM sleep latency. Moreover, we also hypothesized that psilocybin would promote slow-wave activity (SWA) expression in the first sleep cycle, a marker of sleep-related neuroplasticity. Twenty healthy volunteers (10 women, age 28–53) underwent two drug administration sessions, psilocybin or placebo, in a randomized, double-blinded design. Changes in sleep macrostructure, SWA during the first sleep cycle, whole night EEG spectral power across frequencies in non-rapid eye movement (NREM) and REM sleep, and changes in subjective sleep measures were analyzed. The results revealed prolonged REM sleep latency after psilocybin administration and a trend toward a decrease in overall REM sleep duration. No changes in NREM sleep were observed. Psilocybin did not affect EEG power spectra in NREM or REM sleep when examined across the whole night. However, psilocybin suppressed SWA in the first sleep cycle. No evidence was found for sleep-related neuroplasticity, however, a different dosage, timing, effect on homeostatic regulation of sleep, or other mechanisms related to antidepressant effects may play a role. Overall, this study suggests that potential antidepressant properties of psilocybin might be related to changes in sleep.

Evidence Base Update on Assessing Sleep in Youth

BACKGROUND

Sleep is vital to youth well-being and when it becomes disturbed - whether due to environmental or individual factors - mental and physical health suffer. Sleep problems can also be a symptom of underlying mental health disorders. Assessing different components of sleep, including quality and hygiene, can be useful both for identifying mental health problems and for measuring changes in well-being over time. However, there are dozens of sleep-related measures for youth and it can be difficult to determine which to select for a specific research or clinical purpose. The goal of this review was to identify sleep-related measures for clinical and/or research use in youth mental health settings, and to update the evidence base on this topic.

METHOD

We generated a list of candidate measures based on other reviews and searched in PubMed and PsycINFO using the terms "sleep" AND (measure OR assessment OR questionnaire) AND (psychometric OR reliability OR validity). Search results were limited to studies about children and adolescents (aged 2-17) published in English. Additional criteria for inclusion were that there had to be at least three publications reporting on the measure psychometrics in community or mental health populations. Sleep measures meeting these criteria were evaluated using the criteria set by De Los Reyes and Langer (2018).

RESULTS

Twenty-six measures, across four domains of sleep - insomnia, sleep hygiene, sleepiness, sleep quality - met inclusion criteria. Each measure had at least adequate clinical utility. No measure(s) emerged as superior across psychometric domains.

CONCLUSION

Clinicians and researchers must evaluate sleep measures for each use case, as the intended purpose will dictate which measure is best. Future research is necessary to evaluate measure performance in transdiagnostic mental health populations, including youth with serious mental illness.

Polygenic impact of morningness on the overnight dynamics of sleep spindle amplitude

Sleep spindles are thalamocortical oscillations that contribute to sleep maintenance and sleep-related brain plasticity. The current study is an explorative study of the circadian dynamics of sleep spindles in relation to a polygenic score (PGS) for circadian preference towards morningness. The participants represent the 17-year follow-up of a birth cohort having both genome-wide data and an ambulatory sleep electroencephalography measurement available ( N = 154, Mean age = 16.9, SD = 0.1 years, 57% girls). Based on a recent genome-wide association study, we calculated a PGS for circadian preference towards morningness across the whole genome, including 354 single-nucleotide polymorphisms. Stage 2 slow (9-12.5 Hz, N = 186 739) and fast (12.5-16 Hz, N = 135 504) sleep spindles were detected using an automated algorithm with individual time tags and amplitudes for each spindle. There was a significant interaction of PGS for morningness and timing of sleep spindles across the night. These growth curve models showed a curvilinear trajectory of spindle amplitudes: those with a higher PGS for morningness showed higher slow spindle amplitudes in frontal derivations, and a faster dissipation of spindle amplitude in central derivations. Overall, the findings provide new evidence on how individual sleep spindle trajectories are influenced by genetic factors associated with circadian type. The finding may lead to new hypotheses on the associations previously observed between circadian types, psychiatric problems and spindle activity.