The role of retinal irradiance estimates in melanopsin-driven retinal responsivity: A reanalysis of the post-illumination pupil response (PIPR) in seasonal affective disorder.

To isolate melanopsin contributions to retinal sensitivity measured by the post-illumination pupil response (PIPR), controlling for individual differences in non-melanopsin contributions including retinal irradiance is required. When methodologies to negate such differences present barriers, statistical controls have included age, baseline diameter, iris pigmentation, and circadian time of testing. Alternatively, the pupil light reflex (PLR) and calculations estimating retinal irradiance both reflect retinal irradiance, while the PLR also reflects downstream pathways. We reanalyzed data from an observational, correlational study comparing the PIPR across seasons in seasonal affective disorder (SAD) and controls. The PIPR was measured in 47 adults in Pittsburgh, Pennsylvania (25 SAD) over 50 s after 1 s red and blue stimuli of 15.3 log photons/cm2/s. The PLR was within 1 s while PIPR was averaged over 10-40 seconds post-stimulus. Two raters ranked iris pigmentation using a published scale. We evaluated model fit using Akaike's Information Criterion (AIC) across different covariate sets. The best fitting models included either estimated retinal irradiance or PLR, and circadian time of testing. The PLR is collected contemporaneously in PIPR studies and is an individually specific measure of nonspecific effects, while being minimally burdensome. This work extends the prior publication by introducing theoretically grounded covariates that improved analytic model fits based on AIC specific to the present methods and sample. Such quantitative methods could be helpful in studies which must balance participant and researcher burden against tighter methodological controls of individual differences in retinal irradiance.

Sleep quality predicts future mood symptoms in adolescents with bipolar disorder.

BACKGROUND: Poor sleep is prevalent in adolescents with bipolar disorder, precedes illness onset, and is associated with worse mood symptoms. We examined interrelationships between sleep quality and mood symptoms in adolescents with bipolar disorder, particularly effects of sleep quality on emergent mood symptoms. METHODS: Adolescents with bipolar disorder participated in a two-year longitudinal treatment study. Sleep quality (Pittsburgh Sleep Quality Index, PSQI) was assessed quarterly during treatment (baseline, 3-, 6-, 9-, 12-month visits) and twice during follow-up (18-, 24-month visits). Mood symptoms (ALIFE Psychiatric Status Ratings) were retrospectively rated weekly by an independent clinician. Lag models tested whether sleep quality predicted next month's mood symptoms and whether mood symptoms predicted future sleep quality. RESULTS: Adolescents with bipolar disorder had poor sleep quality. Sleep quality initially improved but remained stable thereafter. Worse sleep quality at 6-months predicted worse depression, hypomania, and suicidal ideation the following month. Sleep quality was worse for adolescents who had a suicide attempt during the study compared to those who did not and was worse preceding months with a suicide attempt compared to months without attempts. Alternatively, worse depression predicted worse future sleep quality at baseline, 3-, and 18-months and worse suicidal ideation predicted worse future sleep quality at baseline, 12-, and 18-months. LIMITATIONS: Mood symptoms were rated retrospectively and the PSQI may not capture all dimensions of sleep important for mood symptoms. CONCLUSIONS: Targeted evidence-based sleep treatment in adolescents with bipolar disorder may alleviate sleep problems and have additional benefits on mood symptoms and suicidality risk.

Circadian photoentrainment varies by season and depressed state: associations between light sensitivity and sleep and circadian timing.

STUDY OBJECTIVES: Altered light sensitivity may be an underlying vulnerability for disrupted circadian photoentrainment. The photic information necessary for circadian photoentrainment is sent to the circadian clock from melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs). The current study tested whether the responsivity of ipRGCs measured using the post-illumination pupil response (PIPR) was associated with circadian phase, sleep timing, and circadian alignment, and if these relationships varied by season or depression severity. METHODS: Adult participants (N = 323, agem = 40.5, agesd = 13.5) with varying depression severity were recruited during the summer (n = 154) and winter (n = 169) months. Light sensitivity was measured using the PIPR. Circadian phase was assessed using Dim Light Melatonin Onset (DLMO) on Friday evenings. Midsleep was measured using actigraphy. Circadian alignment was calculated as the DLMO-midsleep phase angle. Multilevel regression models covaried for age, gender, and time since wake of PIPR assessment. RESULTS: Greater light sensitivity was associated with later circadian phase in summer but not in winter (ß = 0.23; p = 0.03). Greater light sensitivity was associated with shorter DLMO-midsleep phase angles (ß = 0.20; p = 0.03) in minimal depression but not in moderate depression (SIGHSAD < 6.6; Johnson-Neyman region of significance). CONCLUSIONS: Light sensitivity measured by the PIPR was associated with circadian phase during the summer but not in winter, suggesting ipRGC functioning in humans may affect circadian entrainment when external zeitgebers are robust. Light sensitivity was associated with circadian alignment only in participants with minimal depression, suggesting circadian photoentrainment, a possible driver of mood, may be decreased in depression year-round, similar to decreased photoentrainment in winter.

Dialectical Behavior Therapy for Adolescents With Bipolar Disorder: A Randomized Clinical Trial.

Importance: Early-onset bipolar disorder conveys substantial risk for suicide. No psychosocial intervention for this population expressly targets suicidal behavior. Objective: To determine whether dialectical behavior therapy (DBT) for adolescents with bipolar spectrum disorder is more effective than standard of care (SOC) psychotherapy in decreasing suicide attempts over 1 year. Design, Settings, and Participants: Adolescents aged 12 to 18 years diagnosed with bipolar spectrum disorder were recruited from a specialty outpatient psychiatric clinic between November 2014 and September 2019. Independent evaluators conducted quarterly assessments over 1 year with participants and parents. Data were analyzed from March 2021 to November 2022. Interventions: Participants were randomly assigned to 1 year of DBT (36 sessions; n = 47) or SOC psychotherapy (schedule clinically determined; n = 53). All youth received medication management via a flexible algorithm. Main Outcomes and Measures: Primary outcomes included suicide attempts over 1 year and mood symptoms and states (depression and hypomania/mania). Secondary analyses included moderation of DBT effects by history of suicide attempt and mediation through emotion dysregulation. Results: Of 100 included participants, 85 (85%) were female, and the mean (SD) age was 16.1 (1.6) years. Participants were followed up over a mean (SD) of 47 (14) weeks. Both treatment groups demonstrated significant and similar improvement in mood symptoms and episodes over 1 year (standardized depression rating scale slope, -0.17; 95% CI, -0.31 to -0.03; standardized mania rating scale slope, -0.24; 95% CI, -0.34 to -0.14). DBT and SOC participants reported similar suicide attempt rates at intake as measured on the Adolescent Longitudinal Follow-Up Evaluation (ALIFE; mean [SD] attempts, 2.0 [4.5] vs 1.8 [3.9], respectively; P = .80). DBT participants reported slightly more suicide attempts at intake as measured on the Columbia-Suicide Severity Rating Scale Pediatric Version (C-SSRS; mean [SD] attempts, 1.4 [3.6] vs 0.6 [0.9]; P = .02). DBT participants reported significantly fewer suicide attempts over follow-up compared with SOC participants via the ALIFE (mean [SD] attempts per follow-up period, 0.2 [0.4] vs 1.1 [4.3], controlling for baseline attempts: P = .03) and the C-SSRS (mean [SD] attempts per follow-up period, 0.04 [0.2] vs 0.10 [0.3], controlling for baseline attempts; P = .03). DBT was significantly more effective than SOC psychotherapy at decreasing suicide attempts over 1 year (ALIFE: incidence rate ratio [IRR], 0.32; 95% CI, 0.11-0.96; C-SSRS: IRR, 0.13; 95% CI, 0.02-0.78). Decreased rate of suicide attempts in DBT was moderated by presence of lifetime history of suicide attempt and time (IRR, 0.23; 95% CI, 0.13-0.44) and mediated by improvement in emotion dysregulation (IRR, 0.61; 95% CI, 0.42-0.89), particularly for those with high baseline emotion dysregulation (standardized ß, -0.59; 95% CI, -0.92 to -0.26). Conclusions and Relevance: In this randomized clinical trial, DBT demonstrated efficacy in decreasing suicide attempts among the high-risk population of adolescents with bipolar spectrum disorder. Trial Registration: ClinicalTrials.gov Identifier: NCT02003690.

The association between cortical gyrification and sleep in adolescents and young adults.

STUDY OBJECTIVES: Healthy sleep is important for adolescent neurodevelopment, and relationships between brain structure and sleep can vary in strength over this maturational window. Although cortical gyrification is increasingly considered a useful index for understanding cognitive and emotional outcomes in adolescence, and sleep is also a strong predictor of such outcomes, we know relatively little about associations between cortical gyrification and sleep. We aimed to identify developmentally invariant (stable across age) or developmentally specific (observed only during discrete age intervals) gyrification-sleep relationships in young people. METHODS: A total of 252 Neuroimaging and Pediatric Sleep Databank participants (9-26 years; 58.3% female) completed wrist actigraphy and a structural MRI scan. Local gyrification index (lGI) was estimated for 34 bilateral brain regions. Naturalistic sleep characteristics (duration, timing, continuity, and regularity) were estimated from wrist actigraphy. Regularized regression for feature selection was used to examine gyrification-sleep relationships. RESULTS: For most brain regions, greater lGI was associated with longer sleep duration, earlier sleep timing, lower variability in sleep regularity, and shorter time awake after sleep onset. lGI in frontoparietal network regions showed associations with sleep patterns that were stable across age. However, in default mode network regions, lGI was only associated with sleep patterns from late childhood through early-to-mid adolescence, a period of vulnerability for mental health disorders. CONCLUSIONS: We detected both developmentally invariant and developmentally specific ties between local gyrification and naturalistic sleep patterns. Default mode network regions may be particularly susceptible to interventions promoting more optimal sleep during childhood and adolescence.

Performance evaluation of the open-source Yet Another Spindle Algorithm sleep staging algorithm against gold standard manual evaluation of polysomnographic records in adolescence.

GOAL AND AIMS: To evaluate an automatic sleep scoring algorithm against manual polysomnography sleep scoring. FOCUS METHOD/TECHNOLOGY: Yet Another Spindle Algorithm automatic sleep staging algorithm. REFERENCE METHOD/TECHNOLOGY: Manual sleep scoring. SAMPLE: 327 nights (151 healthy adolescents), from the NCANDA study. DESIGN: Participants underwent one-to-three overnight polysomnography recordings, one consisting of an event-related-potential paradigm. CORE ANALYTICS: Epoch by Epoch and discrepancy analyses (Bland Altman plots) were conducted on the overall sample. ADDITIONAL ANALYTICS AND EXPLORATORY ANALYSES: Epoch by Epoch and discrepancy analysis were repeated separately on standard polysomnography nights and event-related potential nights. Regression models were estimated on age, sex, scorer, and site of recording, separately on standard polysomnography nights and event-related potential nights. CORE OUTCOMES: The Yet Another Spindle Algorithm sleep scoring algorithm's average sensitivity of 93.04% for Wake, 87.67% for N2, 84.46% for N3, 86.02% for rapid-eye-movement, and 40.39% for N1. Specificity was 96.75% for Wake, 97.31% for N1, 88.87% for N2, 97.99% for N3, and 97.70% for rapid-eye-movement. The Matthews Correlation Coefficient was highest in rapid-eye-movement sleep (0.85) while lowest in N1 (0.39). Cohen's Kappa mirrored Matthews Correlation Coefficient results. In Bland-Altman plots, the bias between Yet Another Spindle Algorithm and human scoring showed proportionality to the manual scoring measurement size. IMPORTANT ADDITIONAL OUTCOMES: Yet Another Spindle Algorithm performance was reduced in event-related-potential/polysomnography nights for N3 and rapid-eye-movement. According to the Matthews Correlation Coefficient, the Yet Another Spindle Algorithm performance was affected by younger age, male sex, recording sites, and scorers. CORE CONCLUSION: Results support the use of Yet Another Spindle Algorithm to score adolescents' polysomnography sleep records, possibly with classification outcomes supervised by an expert scorer.

Subjective and neural reactivity during savoring and rumination.

Repetitive thinking about negative emotions or events is strongly associated with worse mental health, whereas repetitive positive thought is generally believed to be beneficial. This observation is at odds with the idea that all forms of repetitive thinking share underlying neural mechanisms. To resolve this apparent discrepancy, the present study examined relationships between subjective affect and neural mechanisms during periods of sustained processing of positive (savoring) and negative (rumination) emotion. We also examined potential common moderators of savoring and rumination including memory specificity and sleep quality. Results indicated that individuals who experience high positive affect during savoring also are likely to experience more intense negative affect during rumination. fMRI-derived brain activity revealed common mechanisms of rumination and savoring. Memory specificity had common effects on neural correlates of rumination and savoring; sleep quality was not associated with mechanisms of savoring or rumination. These results suggest that repetitive engagement with positive and negative affect is similar both subjectively and mechanistically. Clinical interventions for rumination may benefit from capitalizing on preserved capacity for savoring.

The association between cortical gyrification and sleep in adolescents and young adults.

Study objectives: Healthy sleep is important for adolescent neurodevelopment, and relationships between brain structure and sleep can vary in strength over this maturational window. Although cortical gyrification is increasingly considered a useful index for understanding cognitive and emotional outcomes in adolescence, and sleep is also a strong predictor of such outcomes, we know relatively little about associations between cortical gyrification and sleep. Methods: Using Local gyrification index (lGI) of 34 bilateral brain regions and regularized regression for feature selection, we examined gyrification-sleep relationships in the Neuroimaging and Pediatric Sleep databank (252 participants; 9-26 years; 58.3% female) and identified developmentally invariant (stable across age) or developmentally specific (observed only during discrete age intervals) brain-sleep associations. Naturalistic sleep characteristics (duration, timing, continuity, and regularity) were estimated from wrist actigraphy. Results: For most brain regions, greater lGI was associated with longer sleep duration, earlier sleep timing, lower variability in sleep regularity, and shorter time awake after sleep onset. lGI in frontoparietal network regions showed associations with sleep patterns that were stable across age. However, in default mode network regions, lGI was only associated with sleep patterns from late childhood through early-to-mid adolescence, a period of vulnerability for mental health disorders. Conclusions: We detected both developmentally invariant and developmentally specific ties between local gyrification and naturalistic sleep patterns. Default mode network regions may be particularly susceptible to interventions promoting more optimal sleep during childhood and adolescence.

Elusive hypersomnolence in seasonal affective disorder: actigraphic and self-reported sleep in and out of depressive episodes.

BACKGROUND: Hypersomnolence has been considered a prominent feature of seasonal affective disorder (SAD) despite mixed research findings. In the largest multi-season study conducted to date, we aimed to clarify the nature and extent of hypersomnolence in SAD using multiple measurements during winter depressive episodes and summer remission. METHODS: Sleep measurements assessed in individuals with SAD and nonseasonal, never-depressed controls included actigraphy, daily sleep diaries, retrospective self-report questionnaires, and self-reported hypersomnia assessed via clinical interviews. To characterize hypersomnolence in SAD we (1) compared sleep between diagnostic groups and seasons, (2) examined correlates of self-reported hypersomnia in SAD, and (3) assessed agreement between commonly used measurement modalities. RESULTS: In winter compared to summer, individuals with SAD (n = 64) reported sleeping 72 min longer based on clinical interviews (p < 0.001) and 23 min longer based on actigraphy (p = 0.011). Controls (n = 80) did not differ across seasons. There were no seasonal or group differences on total sleep time when assessed by sleep diaries or retrospective self-reports (p's > 0.05). Endorsement of winter hypersomnia in SAD participants was predicted by greater fatigue, total sleep time, time in bed, naps, and later sleep midpoints (p's < 0.05). CONCLUSION: Despite a winter increase in total sleep time and year-round elevated daytime sleepiness, the average total sleep time (7 h) suggest hypersomnolence is a poor characterization of SAD. Importantly, self-reported hypersomnia captures multiple sleep disruptions, not solely lengthened sleep duration. We recommend using a multimodal assessment of hypersomnolence in mood disorders prior to sleep intervention.

Effects of emerging alcohol use on developmental trajectories of functional sleep measures in adolescents.

STUDY OBJECTIVES: Adolescence is characterized by significant brain development, accompanied by changes in sleep timing and architecture. It also is a period of profound psychosocial changes, including the initiation of alcohol use; however, it is unknown how alcohol use affects sleep architecture in the context of adolescent development. We tracked developmental changes in polysomnographic (PSG) and electroencephalographic (EEG) sleep measures and their relationship with emergent alcohol use in adolescents considering confounding effects (e.g. cannabis use). METHODS: Adolescents (n = 94, 43% female, age: 12-21 years) in the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study had annual laboratory PSG recordings across 4-years. Participants were no/low drinkers at baseline. RESULTS: Linear mixed effect models showed developmental changes in sleep macrostructure and EEG, including a decrease in slow wave sleep and slow wave (delta) EEG activity with advancing age. Emergent moderate/heavy alcohol use across three follow-up years was associated with a decline in percentage rapid eye movement (REM) sleep over time, a longer sleep onset latency (SOL) and shorter total sleep time (TST) in older adolescents, and lower non-REM delta and theta power in males. CONCLUSIONS: These longitudinal data show substantial developmental changes in sleep architecture. Emergent alcohol use during this period was associated with altered sleep continuity, architecture, and EEG measures, with some effects dependent on age and sex. These effects, in part, could be attributed to the effects of alcohol on underlying brain maturation processes involved in sleep-wake regulation.

First-in-human noninvasive left ventricular ultrasound pacing: A potential screening tool for cardiac resynchronization therapy.

Background: A screening tool to predict response to cardiac resynchronization therapy (CRT) could improve patient selection and outcomes. Objective: The purpose of this study was to investigate the feasibility and safety of noninvasive CRT via transcutaneous ultrasonic left ventricular (LV) pacing applied as a screening test before CRT implants. Methods: P-wave-triggered ultrasound stimuli were delivered during bolus dosing of an echocardiographic contrast agent to simulate CRT noninvasively. Ultrasound pacing was delivered at a variety of LV locations with a range of atrioventricular delays to achieve fusion with intrinsic ventricular activation. Three-dimensional cardiac activation maps were acquired via the Medtronic CardioInsight 252-electrode mapping vest during baseline, ultrasound pacing, and after CRT implantation. A separate control group received only the CRT implants. Results: Ultrasound pacing was achieved in 10 patients with a mean of 81.2 ± 50.8 ultrasound paced beats per patient and up to 20 consecutive beats of ultrasound pacing. QRS width at baseline (168.2 ± 17.8 ms) decreased significantly to 117.3 ± 21.5 ms (P <.001) in the best ultrasound paced beat and to 125.8 ± 13.3 ms (P <.001) in the best CRT beat. Electrical activation patterns were similar between CRT pacing and ultrasound pacing with stimulation from the same area of the LV. Troponin results were similar between the ultrasound pacing and the control groups (P = .96), confirming safety. Conclusion: Noninvasive ultrasound pacing before CRT is safe and feasible, and it estimates the degree of electrical resynchronization achievable with CRT. Further study of this promising technique to guide CRT patient selection is warranted.

Morning perception of sleep, stress, and mood, and its relationship with overnight physiological sleep: findings from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study.

This cross-sectional study investigated objective-subjective sleep discrepancies and the physiological basis for morning perceptions of sleep, mood, and readiness, in adolescents. Data collected during a single in-laboratory polysomnographic assessment from 137 healthy adolescents (61 girls; age range: 12-21 years) in the United States National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study were analysed. Upon awakening, participants completed questionnaires assessing sleep quality, mood, and readiness. We evaluated the relationship between overnight polysomnographic, electroencephalographic, sleep autonomic nervous system functioning measures, and next morning self-reported indices. Results showed that older adolescents reported more awakenings, yet they perceived their sleep to be deeper and less restless than younger adolescents. Prediction models including sleep physiology measures (polysomnographic, electroencephalographic, and sleep autonomic nervous system) explained between 3% and 29% of morning sleep perception, mood, and readiness indices. The subjective experience of sleep is a complex phenomenon with multiple components. Distinct physiological sleep processes contribute to the morning perception of sleep and related measures of mood and readiness. More than 70% of the variance (based on a single observation per person) in the perception of sleep, mood, and morning readiness is not explained by overnight sleep-related physiological measures, suggesting that other factors are important for the subjective sleep experience.

Sleep influences daily suicidal ideation through affective reactivity to interpersonal events among high-risk adolescents and young adults.

BACKGROUND: Identifying proximal risk factors for suicidal ideation that are modifiable and relevant for adolescents and young adults is critical for suicide prevention. This study used an intensive monitoring approach to examine whether objectively- and subjectively- measured sleep characteristics predict next-day suicidal ideation occurrence and intensity through affective reactivity to interpersonal events in young people at high risk for suicide. METHODS: Participants included 59 (13-23 years; 76% White; 75% female) adolescents and young adults undergoing intensive outpatient program treatment for depression and suicidality. Participants completed daily ratings of suicidal ideation, sleep quality, and affective reactivity to positive and negative interpersonal events for up to 3 months (M = 56 days, SD = 24.13). Actigraphy captured behavioral sleep duration and timing. Multilevel modeling was used to evaluate within-person fluctuations in sleep and affective reactivity as predictors of suicidal ideation, and multilevel mediation tested the indirect effects of sleep on suicidal ideation via affective reactivity to interpersonal events. RESULTS: Results indicate significant indirect effects of objectively measured sleep duration and subjective sleep quality on next-day suicidal ideation via affective reactivity to negative and positive interpersonal events, respectively. Shorter-than-usual sleep predicted the presence and intensity of next-day suicidal ideation via heightened affective reactivity to negative interpersonal events. Worse sleep quality than usual predicted next-day suicidal ideation via reduced affective reactivity to positive interpersonal events. CONCLUSIONS: Affectivity reactivity is a proximal mechanism through which sleep indices may influence risk for suicidal thinking on a daily basis. Findings highlight the utility of targeting sleep and emotion regulation in suicide prevention among adolescents and young adults at high-risk for suicide.

Sleep intervention and glycemic control in gestational diabetes mellitus: a feasibility study.

BACKGROUND: Over 50% of pregnant people report poor sleep quality and insomnia, with approximately 25% reporting short sleep (<7 hours per night). Short sleep duration is associated with impaired glucose functioning, insulin resistance, and type 2 diabetes mellitus. Although short sleep is associated with elevated blood glucose in patients with gestational diabetes mellitus, it is not known whether education on healthy sleep habits during pregnancy can improve sleep and thus glycemic control in these patients. OBJECTIVE: We developed a sleep education program specific to pregnancy and targeted to patients with gestational diabetes mellitus. We aimed to evaluate the feasibility of this intervention in the setting of a randomized controlled trial. STUDY DESIGN: A sleep education program specific to pregnancy, "Sleep-4-2," was developed via multidisciplinary collaboration between specialists in maternal-fetal medicine, sleep medicine, and psychiatry. The program was presented to focus groups of pregnant people and a separate group of healthcare providers to gauge acceptability of the program and to modify content. This program was then tested on a group of patients diagnosed with gestational diabetes mellitus. Participants were randomized to a group receiving standard gestational diabetes mellitus care or a group participating in the sleep education program. Baseline demographics, sleep knowledge, and self-reported sleep quality information were obtained from all participants at enrollment and again at 35 weeks of pregnancy. Change in sleep knowledge and quality and degree of glycemic control were compared between groups. RESULTS: Between December 2017 and July 2019, 140 patients were screened and 74 were enrolled in the study and randomized. Recruitment to the study was acceptable, with >50% of eligible approached patients agreeing to participate, and retention in the intervention group was high at 94%. We did not demonstrate any difference in sleep knowledge or in the proportion of patients achieving glycemic control during pregnancy. CONCLUSION: Implementation of a sleep education program specific to pregnancy for patients with gestational diabetes mellitus was feasible in the context of typical care. A definitive trial could be developed on the basis of this pilot study to evaluate whether a sleep intervention in pregnancy can improve glycemic control in patients with gestational diabetes mellitus.

Naturalistic Sleep Patterns are Linked to Global Structural Brain Aging in Adolescence.

PURPOSE: We examined whether interindividual differences in naturalistic sleep patterns correlate with any deviations from typical brain aging. METHODS: Our sample consisted of 251 participants without current psychiatric diagnoses (9-25 years; mean [standard deviation] = 17.4 ± 4.52 yr; 58% female) drawn from the Neuroimaging and Pediatric Sleep Databank. Participants completed a T1-weighted structural magnetic resonance imaging scan and 5-7 days of wrist actigraphy to assess naturalistic sleep patterns (duration, timing, continuity, and regularity). We estimated brain age from extracted structural magnetic resonance imaging indices and calculated brain age gap (estimated brain age-chronological age). Robust regressions tested cross-sectional associations between brain age gap and sleep patterns. Exploratory models investigated moderating effects of age and biological gender and, in a subset of the sample, links between sleep, brain age gap, and depression severity (Patient-Reported Outcomes Measurement Information System Depression). RESULTS: Later sleep timing (midsleep) was associated with more advanced brain aging (larger brain age gap), ß = 0.1575, puncorr = .0042, pfdr = .0167. Exploratory models suggested that this effect may be driven by males, although the interaction of gender and brain age gap did not survive multiple comparison correction (ß = 0.2459, puncorr = .0336, pfdr = .1061). Sleep duration, continuity, and regularity were not significantly associated with brain age gap. Age did not moderate any brain age gap-sleep relationships. In this psychiatrically healthy sample, depression severity was also not associated with brain age gap or sleep. DISCUSSION: Later midsleep may be one behavioral cause or correlate of more advanced brain aging, particularly among males. Future studies should examine whether advanced brain aging and individual differences in sleep precede the onset of suboptimal cognitive-emotional outcomes in adolescents.

Sleep and circadian rhythm profiles in seasonal depression.

Sleep and circadian rhythm disruptions are symptoms of, and hypothesized underlying mechanisms in, seasonal depression. Discrepant observational findings and mixed responses to sleep/circadian-based treatments suggest heterogenous sleep and circadian disruptions in seasonal depression, despite these disruptions historically conceptualized as delayed circadian phase and hypersomnia. This study used a data-driven cluster analysis to characterize sleep/circadian profiles in seasonal depression to identify treatment targets for future interventions. Biobehavioral measures of sleep and circadian rhythms were assessed during the winter in individuals with Seasonal Affective Disorder (SAD), subsyndromal-SAD (S-SAD), or nonseasonal, never depressed controls (total sample N = 103). The following variables were used in the cluster analysis: circadian phase (from dim light melatonin onset), midsleep timing, total sleep time, sleep efficiency, regularity of midsleep timing, and nap duration (all from wrist actigraphy). Sleep and circadian variables were compared across clusters and controls. Despite limited sleep/circadian differences between diagnostic groups, there were two reliable (Jaccard Coefficients >0.75) sleep/circadian profiles in SAD/S-SAD individuals: a 'Disrupted sleep' cluster, characterized by irregular and fragmented sleep and an 'Advanced' cluster, characterized by early sleep and circadian timing and longer total sleep times (>7.5 h). Clusters did not differ by depression severity. Midsleep correlated with DLMO (r = 0.56), irregularity (r = 0.3), and total sleep time (r = -0.27). Sleep and circadian disruptions in seasonal depression are not uniformly characterized by hypersomnia and circadian phase delay. Presence of distinct sleep and circadian subgroups in seasonal depression may predict successful treatment response. Prospective assessment and tailoring of individual sleep and circadian disruptions may reduce treatment failures.

A Comprehensive Review of the Literature on Sleep Difficulties and Suicidality in Youth to Inform an Integrative Developmental Model and Future Directions.

Purpose of Review: Suicide is currently the second leading cause of death among youth. Identification of modifiable near-term risk factors can inform suicide prevention strategies. One promising, readily assessed factor is sleep. We critically review the literature on sleep and suicidal thoughts and behaviors among youth. Recent Findings: Most studies examining the youth sleep-suicidality relationship are from epidemiological samples in which both sleep problems and suicidality were assessed over variable timeframes using limited items from scales not designed to measure these constructs. Nonetheless, these data overwhelmingly support an association between suicidality and a range of sleep difficulties (e.g., insomnia, short/long sleep, weekend oversleep), above and beyond depressive symptoms. Limited studies include clinical samples or prospective designs. We review potential mechanisms and present a developmentally-informed integrative model. Summary: Literature supports a clear association between sleep difficulties and youth suicidality. Future directions include prospective longitudinal studies and targeted prevention efforts.

A protocol for applying health equity-informed implementation science models and frameworks to adapt a sleep intervention for adolescents at risk for suicidal thoughts and behaviors.

Background: Effective and equitable strategies to prevent youth suicidal thoughts and behaviors (STB) are an urgent public health priority. Adolescent sleep disturbances are robustly linked to STB but are rarely addressed in preventive interventions or among Black and/or Hispanic/Latinx youth for whom STB risk is increasing disproportionately. This paper describes an application of health equity-informed implementation science models and frameworks to adapt and evaluate the evidence-based Transdiagnostic Sleep and Circadian (TSC) intervention for primary care implementation with adolescents of minoritized backgrounds with depression and STB risk. Methods: This multiphase study protocol uses the Assessment, Decision, Adaptation, Production, Topical Experts-Integration, Training, Testing (ADAPT-ITT) model to adapt and evaluate TSC for primary care implementation with adolescents who are depressed, at risk for STB, and of primarily Black and/or Hispanic/Latinx backgrounds. We integrate the Consolidated Framework for Implementation Research (CFIR) in an initial qualitative inquiry of adolescent, caregiver, and clinician perceptions of TSC. Subsequent ADAPT-ITT phases include systematically and iteratively testing adaptations based on the qualitative inquiry, with ongoing key informant input, and then evaluating the adapted TSC for feasibility, acceptability, and efficacy in a pilot randomized trial. Anticipated results: Based on youth depression and sleep health disparities research, we expect that TSC adaptations will be needed to enhance intervention content for adolescents with depression, STB risk, and primarily Black and/or Hispanic/Latinx backgrounds. We also anticipate adaptations will be needed to align TSC delivery methods with primary care implementation. Conclusions: Adapting evidence-based interventions with end-users and contexts in mind can help ensure that intervention strategies and delivery methods are acceptable to, and feasible with, health disparate populations. Although TSC has shown effectiveness for adolescents with sleep disturbances, we expect that additional multiphase research is necessary to optimize TSC for primary care delivery with Black and/or Hispanic/Latinx adolescents with depression and STB risk.

Physical Exertion Partially Mitigates Task-Switching Deficits From Sleep Loss: Implications for Firefighters.

OBJECTIVE: The aim of the study is to investigate effects of physical exertion on cognitive deficits from sleep loss under conditions that mimic a firefighting scenario. METHODS: Twenty-four male participants completed a crossover study design with 3 conditions: total sleep deprivation, sleep disruption (three 60-minute awakenings), and rested control. Participants then completed 50 minutes of a physical exertion task involving treadmill exercise in a heated room while wearing firefighter protective clothing. Vigilant attention and task-switching performance were assessed pre- and post-sleep manipulation and pre- and post-physical exertion. Vigilant attention was also assessed mid-physical exertion. RESULTS: Total sleep deprivation and sleep disruption increased attentional lapses and task-switching RT. Total sleep deprivation additionally reduced task-switching accuracy. Performance after physical exertion improved only for task-switching RT after total sleep deprivation. CONCLUSIONS: Physical exertion selectively mitigated task-switching RT deficits from the most severe sleep loss condition, total sleep deprivation.