Circadian rhythms, sleep, and substance abuse

Circadian rhythm influences naloxone induced morphine withdrawal and neuronal activity of lateral paragigantocellularis nucleus

Investigations have shown that the circadian rhythm can affect the mechanisms associated with drug dependence. In this regard, we sought to assess the negative consequence of morphine withdrawal syndrome on conditioned place aversion (CPA) and lateral paragigantocellularis (LPGi) neuronal activity in morphine-dependent rats during light (8:00-12:00) and dark (20:00-24:00) cycles. Male Wistar rats (250-300 g) were received 10 mg/kg morphine or its vehicle (Saline, 2 mL/kg/12 h, s.c.) in 13 consecutive days for behavioral assessment tests. Then, naloxone-induced conditioned place aversion and physical signs of withdrawal syndrome were evaluated during light and dark cycles. In contrast to the behavioral part, we performed in vivo extracellular single-unit recording for investigating the neural response of LPGi to naloxone in morphine-dependent rats on day 10 of morphine/saline exposure. Results showed that naloxone induced conditioned place aversion in both light and dark cycles, but the CPA score during the light cycle was larger. Moreover, the intensity of physical signs of morphine withdrawal syndrome was more severe during the light cycle (rest phase) compare to the dark one. In electrophysiological experiments, results indicated that naloxone evoked both excitatory and inhibitory responses in LPGi neurons and the incremental effect of naloxone on LPGi activity was stronger in the light cycle. Also, the neurons with the excitatory response exhibited higher baseline activity in the dark cycle, but the neurons with the inhibitory response showed higher baseline activity in the light cycle. Interestingly, the baseline firing rate of neurons recorded in the light cycle was significantly different in response (excitatory/inhibitory) -dependent manner. We concluded that naloxone-induced changes in LPGi cellular activity and behaviors of morphine-dependent rats can be affected by circadian rhythm and the internal clock.

Psychostimulant Use Disorder, an Unmet Therapeutic Goal: Can Modafinil Narrow the Gap?

The number of individuals affected by psychostimulant use disorder (PSUD) has increased rapidly over the last few decades resulting in economic, emotional, and physical burdens on our society. Further compounding this issue is the current lack of clinically approved medications to treat this disorder. The dopamine transporter (DAT) is a common target of psychostimulant actions related to their use and dependence, and the recent availability of atypical DAT inhibitors as a potential therapeutic option has garnered popularity in this research field. Modafinil (MOD), which is approved for clinical use for the treatment of narcolepsy and sleep disorders, blocks DAT just like commonly abused psychostimulants. However, preclinical and clinical studies have shown that it lacks the addictive properties (in both behavioral and neurochemical studies) associated with other abused DAT inhibitors. Clinical availability of MOD has facilitated its off-label use for several psychiatric disorders related to alteration of brain dopamine (DA) systems, including PSUD. In this review, we highlight clinical and preclinical research on MOD and its R-enantiomer, R-MOD, as potential medications for PSUD. Given the complexity of PSUD, we have also reported the effects of MOD on psychostimulant-induced appearance of several symptoms that could intensify the severity of the disease (i.e., sleep disorders and impairment of cognitive functions), besides the potential therapeutic effects of MOD on PSUD.

Associations Among Sleep and Cancer Risk Behaviors: a Scoping Review of Experimental Studies in Healthy Adult Populations

BACKGROUND

Links among poor sleep and cancer risk behaviors have been largely overlooked in the context of cancer prevention and behavioral medicine. The goal of this scoping review was to determine the extent and nature of experimental studies conducted with healthy adult populations that tested the associations among poor sleep and cancer risk behaviors.

METHOD

Electronic databases and major sleep journals were searched to identify experimental studies in healthy adult samples published through January 2018. Studies examined associations among eight pairings of manipulated behaviors and outcomes ("independent variable (IV)-outcome pairs"): the impact of sleep manipulations on physical activity (PA), diet, alcohol consumption, and tobacco use outcomes; and the impact of PA, diet, alcohol consumption, and tobacco use manipulations on sleep outcomes. Studies were characterized in terms of sample characteristics; study design; IV type, dose, and duration; and outcome measurement and duration.

RESULTS

Abstracts of 5697 papers and 345 full texts were screened. Eighty-eight studies describing 125 comparisons met inclusion criteria. Only two studies tested the association between tobacco use and sleep; none tested whether sleep influenced alcohol consumption. Sample sizes were typically small, most studies used crossover designs, and studies tended to include younger and more male participants. Within each IV-outcome pair, there was substantial heterogeneity in how behaviors were manipulated, outcome measurement, and type of control group. Few studies assessed mechanisms.

CONCLUSION

There is a need for larger experimental studies with more representative samples. Overall, heterogeneity and limitations in study designs make it difficult to synthesize evidence across studies.

Associations between adolescent sleep deficiency and prescription opioid misuse in adulthood

STUDY OBJECTIVES

The main aim of this study was to estimate the association between sleep deficiency in adolescence and subsequent prescription opioid misuse in adulthood using United States nationally representative longitudinal data.

METHODS

Self-reported data captured in the National Longitudinal Study of Adolescent to Adult Health at baseline (Wave 1; mean age = 16 years) and 12 year follow-up (Wave 4; mean age = 29 years). Participants (n = 12,213) reported on four measures of sleep during adolescence (Wave 1) and on lifetime prescription opioid misuse during adulthood (Wave 4). Associations between adolescent sleep and adult opioid misuse were estimated using multivariate logistic regression analysis controlling for sociodemographics, chronic pain, mental health, childhood adverse events, and a history of substance use.

RESULTS

During adolescence, 59.2% of participants reported sleep deficiency. Prospectively, adolescents reporting not getting enough sleep, chronic unrestful sleep, and insomnia were associated with an increased risk for prescription opioid misuse (adjusted odds ratios [OR] = 1.2, p < 0.005 for all three variables). Short sleep duration was not associated with opioid misuse.

CONCLUSION

This is the first study to longitudinally link sleep deficiency as an independent risk factor for the development of prescription opioid misuse. Sleep deficiency could be a driver of the opioid crisis affecting young people in the United States. Future studies should determine whether early and targeted sleep interventions may decrease risk for opioid misuse in high-risk patients prescribed opioids for pain.

Gene Expression Profiling in the Striatum of Per2 KO Mice Exhibiting More Vulnerable Responses against Methamphetamine

Drug addiction influences most communities directly or indirectly. Increasing studies have reported the relationship between circadian-related genes and drug addiction. Per2 disrupted mice exhibited more vulnerable behavioral responses against some drugs including methamphetamine (METH). However, its roles and mechanisms are still not clear. Transcriptional profiling analysis in Per2 knockout (KO) mice may provide a valuable tool to identify potential genetic involvement and pathways in enhanced behavioral responses against drugs. To explore the potential genetic involvement, we examined common differentially expressed genes (DEGs) in the striatum of drug naïve Per2 KO/wild-type (WT) mice, and before/after METH treatment in Per2 KO mice, but not in WT mice. We selected 9 common DEGs (Ncald, Cpa6, Pklr, Ttc29, Cbr2, Egr2, Prg4, Lcn2, and Camsap2) based on literature research. Among the common DEGs, Ncald, Cpa6, Pklr, and Ttc29 showed higher expression levels in drug naïve Per2 KO mice than in WT mice, while they were downregulated in Per2 KO mice after METH treatment. In contrast, Cbr2, Egr2, Prg4, Lcn2, and Camsap2 exhibited lower expression levels in drug naïve Per2 KO mice than in WT mice, while they were upregulated after METH treatment in Per2 KO mice. qRT-PCR analyses validated the expression patterns of 9 target genes before/after METH treatment in Per2 KO and WT mice. Although further research is required to deeply understand the relationship and roles of the 9 target genes in drug addiction, the findings from the present study indicate that the target genes might play important roles in drug addiction.

Translational Sleep Science in Behavioral Medicine: Introduction to this Special Issue

The consideration of sleep and circadian rhythms in the context of health is a relatively recent development in the history of the field of behavioral medicine. This special issue of the International Journal of Behavioral Medicine recognizes that sleep and circadian rhythms are fundamental to appreciating physiological, psychological, social, and environmental factors in the health and well-being of the population. The articles included in this issue draw attention to the breadth and saliency of sleep as a marker of health status and as a target of behavioral intervention to promote health. Such research highlights the diversity of participants, research methods, and clinical significance of translational sleep science allowing us to recognize the role of sleep in the context of health in new ways. These studies also illustrate progress in integrating theory, employing prospective and longitudinal designs and multimodal and integrative assessments. This introduction to the special issue concludes by discussing challenges and opportunities in the field of behavioral sleep medicine, including those posed by the coronavirus disease 2019 (COVID-19) pandemic and the need to more effectively provide sleep disorder treatment among underserved populations.

Exploring the relationship of sleep quality with drug use and substance abuse among university students: a cross-cultural study

Background

There is a growing interest in studying the area of drugs and college students due to the negative effects that drugs have on a student’s social life, academics, psychology, finances, and health. So, this study aims to identify the relationship between drug/substance abuse and quality of sleep among university students in Yemen and Saudi Arabia.

The sample size was 935 (43.21% N = 404 female, 56.79% N = 531 male, 55.40% N = 518 Yemeni, and 44.60% N = 417 Saudi). Students responded to the Drug Abuse Screening Test (DAST-10), the Pittsburgh Sleep Quality Index (PSQI), and the Substance Abuse Questionnaire.

Results

The results showed a high prevalence of drug use: 43.1% of respondents (27.27% N = 219 Yemenis and 15.83% N = 148 Saudis) abuse drugs, 29.41% were in the low level of drug use, 10.48% were in the moderate level of drug use, 2.46% were in the substantial level of drug, and 0.75% were in the severe level of drug use as per the DAST-10. The differences between both countries in terms of drug use were significant (X2 19.394, P < 0.001). The prevalence rate of inhalants was 16.36% and of sedatives was 12.09%, and the differences between countries were significant. The prevalence of poor sleep quality was 24.81%; a total of 7.91% of respondents had very poor sleep quality, while 16.90% had poor sleep quality. The differences between countries were not significant.

The relationship between sleep quality and drug use, smoking, and substance abuse was significant. The quality of sleep decreased consistently with a high level of drug use or substance abuse.

Conclusions

Poor sleep quality is significantly associated with drug use and substance abuse, and it is important to recognize the factors affecting drug and substance abuse among university students. A significant contribution can make for the protection of university students by guaranteeing that psychological interventions for high-risk groups are planned in advance.

Risk of alcohol use disorders in patients with insomnia: A population-based retrospective cohort study

BACKGROUND

The aim of this study was to explore the risk of alcohol use disorders (AUDs) in patients with insomnia.

METHODS

This was a population-based retrospective cohort study based on data from 2000 to 2013. Data from the Taiwan National Health Insurance Research Database were employed for this study. A total of 8076 patients with insomnia were identified as the study group. The control group comprised 16,152 age- and sex-matched patients. We conducted a Cox proportional hazard regression analysis to estimate the effects of insomnia on the risk of AUDs.

RESULTS

The overall incidence of AUDs was 753.71 per 100,000 person-years for patients with insomnia, which was significantly higher than the incidence for those in the control group (377.73 per 100,000 person-years). Overall, patients with insomnia had a higher risk of AUDs than did those in the control group (adjusted hazard ratio [HR] = 1.75, 95% confidence interval [CI] = 1.42-2.10). We also observed a significantly higher risk of AUDs in patients with both insomnia and depression (adjusted HR = 5.85; 95% CI = 3.13-8.88) than in those without these conditions.

CONCLUSIONS

The risk of AUDs in patients with insomnia was found to be significantly higher than that in individuals in the control group; the risk was particularly pronounced among those with insomnia and depression. These conditions thus exhibited a joint effect on AUDs risk.

A Preliminary Investigation of the Underlying Mechanism Associating Daily Sleep Continuity Disturbance and Prescription Opioid Use Among Individuals With Sickle Cell Disease

BACKGROUND

There are emerging data indicating that sleep disturbance may be linked with an increase in opioid use. The majority of sickle cell disease (SCD) patients experience sleep disturbances, which can elevate pain severity and pain catastrophizing, both of which are important predictors of opioid consumption.

PURPOSE

We conducted a preliminary investigation on the association between previous night sleep disturbance and short-acting opioid use, as well as the potential mediating roles of pain severity and pain catastrophizing. Because sex is associated with sleep disturbance, pain-related experiences, and opioid use, we also explored the potential moderating role of sex.

METHODS

Participants were 45 SCD patients who were prescribed opioids. For 3 months, sleep diaries were collected immediately upon participants' awakening. Daily pain severity, pain catastrophizing, and prescription opioid use measures were collected before bedtime.

RESULTS

Multilevel structural equation modeling revealed that wake time after sleep onset (WASO) during the previous night (Time 1) predicted greater short-acting opioid use during the next day (Time 2). Pain severity and pain catastrophizing measured during the next day (Time 2) also mediated the association between the two. Sex moderation analysis showed that the positive association between WASO and pain severity was largely driven by women.

CONCLUSION

These findings provide some preliminary evidence as to the mechanism linking sleep continuity disturbance and opioid requirement in SCD patients. Future studies should replicate and extend these findings with clearer temporal information and employing more refined measures of sleep continuity and prescription opioid use in a larger sample.

Is there a 24-hour rhythm in alcohol craving and does it vary by sleep/circadian timing?

Increasing evidence implicates sleep/circadian factors in alcohol use; however, the role of such factors in alcohol craving has received scant attention. Prior research suggests a 24-hour rhythm in related processes (e.g., reward motivation), but more research directly investigating a rhythm in craving is needed. Moreover, prior evidence is ambiguous whether such a rhythm in alcohol craving may vary by sleep/circadian timing. To examine these possibilities, 36 late adolescents (18-22 years of age; 61% female) with regular alcohol use but without a current alcohol use disorder were recruited to complete smartphone reports of alcohol craving intensity six times a day for two weeks. During these two weeks, participants wore wrist actigraphs and completed two in-lab assessments (on Thursday and Sunday) of dim light melatonin onset (DLMO). Average actigraphically derived midpoint of sleep on weekends and average DLMO were used as indicators of sleep and circadian timing, respectively. Multilevel cosinor analysis revealed a 24-hour rhythm in alcohol craving. Findings across the sleep and circadian timing variables converged to suggest that sleep/circadian timing moderated the 24-hour rhythm in alcohol craving. Specifically, people with later sleep/circadian timing had later timing of peak alcohol craving. These findings add to the growing evidence of potential circadian influences on reward-related phenomena and suggest that greater consideration of sleep and circadian influences on alcohol craving may be useful for understanding alcohol use patterns and advancing related interventions.

Cocaine-mediated circadian reprogramming in the striatum through dopamine D2R and PPARγ activation

Substance abuse disorders are linked to alteration of circadian rhythms, although the molecular and neuronal pathways implicated have not been fully elucidated. Addictive drugs, such as cocaine, induce a rapid increase of dopamine levels in the brain. Here, we show that acute administration of cocaine triggers reprogramming in circadian gene expression in the striatum, an area involved in psychomotor and rewarding effects of drugs. This process involves the activation of peroxisome protein activator receptor gamma (PPARγ), a nuclear receptor involved in inflammatory responses. PPARγ reprogramming is altered in mice with cell-specific ablation of the dopamine D2 receptor (D2R) in the striatal medium spiny neurons (MSNs) (iMSN-D2RKO). Administration of a specific PPARγ agonist in iMSN-D2RKO mice elicits substantial rescue of cocaine-dependent control of circadian genes. These findings have potential implications for development of strategies to treat substance abuse disorders.

Drugs of abuse have been shown to perturb circadian rhythms. Here, the authors show in mice that cocaine exposure modulates circadian gene expression in the striatum through a previously unappreciated pathway that involves dopamine D2 receptors and the nuclear receptor PPARγ.

Memory and the circadian system: Identifying candidate mechanisms by which local clocks in the brain may regulate synaptic plasticity

The circadian system is an endogenous biological network responsible for coordinating near-24-h cycles in behavior and physiology with daily timing cues from the external environment. In this review, we explore how the circadian system regulates memory formation, retention, and recall. Circadian rhythms in these memory processes may arise through several endogenous pathways, and recent work highlights the importance of genetic timekeepers found locally within tissues, called local clocks. We evaluate the circadian memory literature for evidence of local clock involvement in memory, identifying potential nodes for direct interactions between local clock components and mechanisms of synaptic plasticity. Our discussion illustrates how local clocks may pervasively modulate neuronal plastic capacity, a phenomenon that we designate here as circadian metaplasticity. We suggest that this function of local clocks supports the temporal optimization of memory processes, illuminating the potential for circadian therapeutic strategies in the prevention and treatment of memory impairment.

[Characteristics of sleep disturbances related to substance use disorders]

Sleep disturbances are frequently observed in patients with substance use disorders during active use as well as in withdrawal period and in remission. However, there is limited information about the association between sleep disturbances and substance use disorders. This review summarizes results of the studies on specific characteristics of sleep disturbances related to alcohol, opioids and psychostimulants (cocaine) use. Data on objective and subjective measurements of sleep characteristics at different stages of the course of an addiction disorder (active use, withdrawal, remission) are presented.

Association of Delaying School Start Time With Sleep Duration, Timing, and Quality Among Adolescents

IMPORTANCE

Sleep is a resource that has been associated with health and well-being; however, sleep insufficiency is common among adolescents.

OBJECTIVE

To examine how delaying school start time is associated with objectively assessed sleep duration, timing, and quality in a cohort of adolescents.

DESIGN, SETTING, AND PARTICIPANTS

This observational cohort study took advantage of district-initiated modifications in the starting times of 5 public high schools in the metropolitan area of Minneapolis and St Paul, Minnesota. A total of 455 students were followed up from grade 9 (May 3 to June 3, 2016) through grade 11 (March 15 to May 21, 2018). Data were analyzed from February 1 to July 24, 2019.

EXPOSURES

All 5 participating schools started early (7:30 am or 7:45 am) at baseline (2016). At follow-up 1 (2017) and continuing through follow-up 2 (2018), 2 schools delayed their start times by 50 and 65 minutes, whereas 3 comparison schools started at 7:30 am throughout the observation period.

MAIN OUTCOMES AND MEASURES

Wrist actigraphy was used to derive indices of sleep duration, timing, and quality. With a difference-in-difference design, linear mixed-effects models were used to estimate differences in changes in sleep time between delayed-start and comparison schools.

RESULTS

A total of 455 students were included in the analysis (among those identifying sex, 225 girls [49.5%] and 219 boys [48.1%]; mean [SD] age at baseline, 15.2 [0.3] years). Relative to the change observed in the comparison schools, students who attended delayed-start schools had an additional mean 41 (95% CI, 25-57) objectively measured minutes of night sleep at follow-up 1 and 43 (95% CI, 25-61) at follow-up 2. Delayed start times were not associated with falling asleep later on school nights at follow-ups, and students attending these schools had a mean difference-in-differences change in weekend night sleep of -24 (95% CI, -51 to 2) minutes from baseline to follow-up 1 and -34 (95% CI, -65 to -3) minutes from baseline to follow-up 2, relative to comparison school participants. Differences in differences for school night sleep onset, weekend sleep onset latency, sleep midpoints, sleep efficiency, and the sleep fragmentation index between the 2 conditions were minimal.

CONCLUSIONS AND RELEVANCE

This study found that delaying high school start times could extend adolescent school night sleep duration and lessen their need for catch-up sleep on weekends. These findings suggest that later start times could be a durable strategy for addressing population-wide adolescent sleep deficits.

Measurable health effects associated with the daylight saving time shift

The transition to daylight saving time (DST) is beneficial for energy conservation but at the same time it has been reported to increase the risk of cerebrovascular and cardiovascular problems. Here, we evaluate the effect of the DST shift on a whole spectrum of diseases-an analysis we hope will be helpful in weighing the risks and benefits of DST shifts. Our study relied on a population-based, cross-sectional analysis of the IBM Watson Health MarketScan insurance claim dataset, which incorporates over 150 million unique patients in the US, and the Swedish national inpatient register, which incorporates more than nine million unique Swedes. For hundreds of sex- and age-specific diseases, we assessed effects of the DST shifts forward and backward by one hour in spring and autumn by comparing the observed and expected diagnosis rates after DST shift exposure. We found four prominent, elevated risk clusters, including cardiovascular diseases (such as heart attacks), injuries, mental and behavioral disorders, and immune-related diseases such as noninfective enteritis and colitis to be significantly associated with DST shifts in the United States and Sweden. While the majority of disease risk elevations are modest (a few percent), a considerable number of diseases exhibit an approximately ten percent relative risk increase. We estimate that each spring DST shift is associated with negative health effects-with 150,000 incidences in the US, and 880,000 globally. We also identify for the first time a collection of diseases with relative risks that appear to decrease immediately after the spring DST shift, enriched with infections and immune system-related maladies. These diseases' decreasing relative risks might be driven by the documented boosting effect of a short-term stress (such as that experienced around the spring DST shift) on the immune system.

Onset of regular cannabis use and young adult insomnia: an analysis of shared genetic liability

STUDY OBJECTIVES

Estimate the genetic and environmental influences on the relationship between onset of regular cannabis use and young adult insomnia.

METHODS

In a population-based twin cohort of 1882 twins (56% female, mean age = 22.99, SD = 2.97) we explored the genetic/environmental etiology of the relationship between onset of regular cannabis use and insomnia-related outcomes via multivariate twin models.

RESULTS

Controlling for sex, current depression symptoms, and prior diagnosis of an anxiety or depression disorder, adult twins who reported early onset for regular cannabis use (age 17 or younger) were more likely to have insomnia (β = 0.07, p = 0.024) and insomnia with short sleep on weekdays (β = 0.08, p = 0.003) as young adults. We found significant genetic contributions for the onset of regular cannabis use (a2 = 76%, p < 0.001), insomnia (a2 = 44%, p < 0.001), and insomnia with short sleep on weekdays (a2 = 37%, p < 0.001). We found significant genetic correlations between onset of regular use and both insomnia (rA = 0.20, p = 0.047) and insomnia with short sleep on weekdays (rA = 0.25, p = 0.008) but no significant environmental associations between these traits.

CONCLUSIONS

We found common genetic liabilities for early onset of regular cannabis use and insomnia, implying pleiotropic influences of genes on both traits.

Alterations in circadian rhythms following alcohol use: A systematic review

Increasing evidence suggest a bidirectional link between disrupted circadian rhythms and alcohol use disorders (AUD). A better understanding of these alcohol-induced changes in circadian rhythms will likely provide important therapeutic solutions. We conducted a systematic review based on the PubMed database examining biological rhythms in all stages of alcohol use: acute alcohol consumption, AUD, alcohol withdrawal, and abstinence. Different changes in circadian rhythms have been observed after a single acute alcohol intake, but also during AUD and alcohol withdrawal. Following a single acute alcohol intake, changes in biological rhythms are dose-dependent, reflected in the melatonin and cortisol secretions, and the core body temperature (CBT) rhythms. These alterations normalize the next morning and appear mostly for acute alcohol intake higher than 0.5 g/kg. These alterations are more severe during AUD and persist over time. In addition, interestingly, opposite patterns of the melatonin physiological ratio between diurnal and nocturnal secretion (N/D ratio < 1) have been observed during AUD and appear to be a marker of chronic daily use. During alcohol withdrawal, circadian rhythms desynchronization correlates with the severity of alcohol withdrawal symptoms and withdrawal complications such as delirium tremens. During abstinence a resynchronization of circadian rhythms of cortisol and CBT appears in most patients about 1 month after alcohol withdrawal. Disruption of melatonin circadian rhythms can persist after 3-12 weeks of abstinence. The circadian genetic vulnerability associated with biological rhythms alterations in alcohol use disorders increases the risk of relapses. Circadian-based interventions could play a critical role in preventing and treating AUD.

Lifestyle and Shiftwork: Designing and Testing a Model for Health Promotion of Iranian Nurses

BACKGROUND: Lifestyle is one factor that forms the nurses' health, particularly those who work in shiftwork schedules. AIMS: The aim of this study was to design and test a model for health promotion of Iranian nurses. In this model, nurses' lifestyle was considered as the precedent, physical and mental health as the outcomes, and sleep disturbance and chronic fatigue as the mediators. METHODS: A cross-sectional study using structural equation modeling was conducted among 240 shiftworker nurses in Iran. The data collection was performed using the Persian versions of the Survey of Shiftworkers Questionnaire and Life Style Questionnaire. Bootstrap in Preacher and Hayes' Macro program was used for testing mediation. RESULTS: Lifestyle had a weak significant direct effect on physical (β = 0.13, p < .04) and mental health (β = 0.12, p < .02), and it had a significant indirect effect on physical health via chronic fatigue (β = -0.11, p < .001) and sleep disturbance (β = -0.05, p < .01). This variable only had a significant indirect effect on mental health via chronic fatigue (β = -0.19, p < .001). The final model proposed a new significant path between sleep disturbances and chronic fatigue (β = 0.22, p < .001). CONCLUSIONS: Therefore, the hospital officials can enhance the nurses' physical and mental well-being by providing interventions and training courses on aspects of healthy lifestyles, such as physical activity, avoidance of smoking, and maintenance of body weight.

Timing of Morphine Administration Differentially Alters Paraventricular Thalamic Neuron Activity

The paraventricular thalamic nucleus (PVT) is a brain region involved in regulating arousal, goal-oriented behaviors, and drug seeking, all key factors playing a role in substance use disorder. Given this, we investigated the temporal effects of administering morphine, an opioid with strongly addictive properties, on PVT neuronal function in mice using acute brain slices. Here, we show that morphine administration and electrophysiological recordings that occur during periods of animal inactivity (light cycle) elicit increases in PVT neuronal function during a 24-h abstinence time point. Furthermore, we show that morphine-induced increases in PVT neuronal activity at 24-h abstinence are occluded when morphine administration and recordings are performed during an animals' active state (dark cycle). Based on our electrophysiological results combined with previous findings demonstrating that PVT neuronal activity regulates drug-seeking behaviors, we investigated whether timing morphine administration with periods of vigilance (dark cycle) would decrease drug-seeking behaviors in an animal model of substance use disorder. We found that context-induced morphine-seeking behaviors were intact regardless of the time morphine was administered (e.g., light cycle or dark cycle). Our electrophysiological results suggest that timing morphine with various states of arousal may impact the firing of PVT neurons during abstinence. Although, this may not impact context-induced drug-seeking behaviors.

Psychopathy and chronotype disposition: the mediating role of depression

This study examined the relationship between dark triad personality traits and chronotype disposition, whilst incorporating the mediating role of anxiety and/or depression after excluding individuals presenting insomnia and/or physiological sleep-disorder symptoms. Members of the general population (N = 453) completed online measures of dark triad personality traits, chronotype, and anxious and depressive symptoms. Psychopathy and Machiavellianism were independently related to an evening chronotype disposition. However, after accounting for age, sex, anxiety and depression, psychopathy and depression remained the only significant predictors of chronotype. Therefore, whilst psychopathy was the strongest predictor of an evening chronotype preference, this relationship is partially mediated by depression. Individuals presenting an evening disposition may display increased psychopathic traits due to greater emotion dysregulation. This is potentially perpetuated by depressive symptoms stemming from a delayed or blunted affective rhythm. Interacting factors (e.g. reduced light exposure) may also contribute to alterations in the biological rhythm amongst evening-types, resulting in a negative feedback cycle. Targeting chronotype and depressive symptoms amongst individuals presenting psychopathic tendencies could increase the efficacy of existing sleep-based interventions for hostile behaviour.

Neural circuits linking sleep and addiction: Animal models to understand why select individuals are more vulnerable to substance use disorders after sleep deprivation

Individuals differ widely in their drug-craving behaviors. One reason for these differences involves sleep. Sleep disturbances lead to an increased risk of substance use disorders and relapse in only some individuals. While animal studies have examined the impact of sleep on reward circuitry, few have addressed the role of individual differences in the effects of altered sleep. There does, however, exist a rodent model of individual differences in reward-seeking behavior: the sign/goal-tracker model of Pavlovian conditioned approach. In this model, only some rats show the key behavioral traits associated with addiction, including impulsivity and poor attentional control, making this an ideal model system to examine individually distinct sleep-reward interactions. Here, we describe how the limbic neural circuits responsible for individual differences in incentive motivation overlap with those involved in sleep-wake regulation, and how this model can elucidate the common underlying mechanisms. Consideration of individual differences in preclinical models would improve our understanding of how sleep interacts with motivational systems, and why sleep deprivation contributes to addiction in only select individuals.

Insomnia in personality disorders and substance use disorders

The relationship between certain personality disorders (PDs) and insomnia has been the object of few studies in recent years. Even though it is not indicated to use polysomnography to diagnose insomnia, objective measures have shown sleep abnormalities in individuals with a personality disorder and insomnia. Interestingly, there is increasing evidence that emotion dysregulation is involved in a mutually aggravating relationship between Borderline Personality Disorder (BPD) and insomnia. While BPD traits are highly associated with suicide ideation and attempts, these behaviors could be potentiated or enhanced in individuals presenting sleep disturbances. Because BPD and other mental disorders are often linked with the use of medication or other substances, it is also important to review the association between substance use disorders (SUD) and insomnia. SUD can disrupt sleep and foster insomnia, which in turn might increase motivation to use substances. Insomnia has also been shown to precede (i.e., predict) SUD, and can be present during withdrawal as well. These results highlight the need to assess and treat insomnia when working with patients who present a PD or SUD.

Onset of regular cannabis use and adult sleep duration: Genetic variation and the implications of a predictive relationship

BACKGROUND

Limited evidence suggests that early cannabis use is associated with sleep problems. Research is needed to understand the developmental impact of early regular cannabis use on later adult sleep duration.

METHODS

In a sample of 1656 adult twins (56% female, Mean age = 25.79yrs), linear mixed effects models were used to analyze the influence of retrospectively assessed age of onset of regular cannabis use on adult sleep duration controlling for sex, depression, and current substance use. Twin analyses provided genetic and environmental variance estimates as well as insights into the association and potential casual relationships between these traits.

RESULTS

Earlier age of onset for regular cannabis use was significantly associated with shorter adult sleep duration on both weekdays (β = -0.13, 95% CI = [-0.23, -0.04]) and weekends (β = -0.18, 95% CI = [-0.27, -0.08]). Additive genetics significantly contributed to the onset of regular cannabis use (a² = 76%, 95% CI = [68, 85]) and adult weekend sleep duration (a² = 20%, 95% CI = [11, 32]). We found evidence of a significant genetic correlation (r_A = -0.31, 95% CI = [-0.41, -0.15]) between these two traits and our best fitting model was consistent with early onset of regular cannabis use causing shorter adult weekend sleep duration (β = -0.11, 95% CI = [-0.18, -0.03]).

CONCLUSIONS

Our results are consistent with the hypothesis that early onset of regular cannabis use may have a negative impact on adult sleep duration.

Sleep and circadian risk factors for alcohol problems: a brief overview and proposed mechanisms

Disturbances in sleep and circadian rhythms may be important, albeit underappreciated, risk factors for the initiation of alcohol use and the escalation of alcohol problems. In this review, we first describe sleep and circadian changes during adolescence and young adulthood. Second, we explain how these sleep/circadian changes intersect with onset and escalation of alcohol use. Third, we briefly note how alcohol use (whether acute or chronic) affects sleep and circadian rhythms. Finally, we articulate a conceptual model containing two mechanistic pathways-broadly positive and negative reinforcement-linking sleep/circadian factors to alcohol involvement before listing key areas we believe are ripe for further inquiry.

The circadian gene, Per2, influences methamphetamine sensitization and reward through the dopaminergic system in the striatum of mice

Drug addiction is a chronic and relapsing brain disorder, influenced by complex interactions between endogenous and exogenous factors. Per2, a circadian gene, plays a role in drug addiction. Previous studies using Per2-knockout mice have shown a role for Per2 in cocaine, morphine and alcohol addiction. In the present study, we investigated the role of Per2 in methamphetamine (METH) addiction using Per2-overexpression and knockout mice. We observed locomotor sensitization responses to METH administration, and rewarding effects using a conditioned place preference test. In addition, we measured expression levels of dopamine and dopamine-related genes (monoamine oxidase A, DA receptor 1, DA receptor 2, DA active transporter, tyrosine hydroxylase and cAMP response element-binding protein 1) in the striatum of the mice after repeated METH treatments, using qRT-PCR. Per2-overexpressed mice showed decreased locomotor sensitization and rewarding effects of METH compared to the wildtype mice, whereas the opposite was observed in Per2 knockout mice. Both types of transgenic mice showed altered expression levels of dopamine-related genes after repeated METH administration. Specifically, we observed lower dopamine levels in Per2-overexpressed mice and higher levels in Per2-knockout mice. Taken together, Per2 expression levels may influence the addictive effects of METH through the dopaminergic system in the striatum of mice.

Meta-analysis of alcohol induced gut dysbiosis and the resulting behavioral impact

About 99% of the unique genes and almost half of the cells found in the human body come from microbes including bacteria, archaea, fungi, and viruses. Collectively these microorganisms contribute to the microbiome and often reside in the gut. The gut microbiome plays an important role in the body and contributes to digestive health, the immune system, and brain function. The gut microbiome interacts with the central nervous system through the vagal pathways as well as the endocrine or immune pathways. Changes in the proportion or diversity of the microbiota can have an impact on normal physiology and has been implicated in inflammation, depression, obesity, and addiction. Several animal studies suggest the involvement of gut microbiome in the regulation of pain, emotion, and cognition. Alcoholism has been linked with gut microbiome dysbiosis and thus can have deleterious effects on the gut-brain axis balance. Gut microbiome produces important metabolites such as gastrointestinal hormones, short chain fatty acids, precursors to the neuroactive compounds and neurotransmitters that impact the physiology and normal functioning of the body. The microbiome imbalance has been correlated with behavioral changes and alcohol dependence in the host. The objective of this study is to elucidate the link between alcohol induced gut microbiota dysbiosis and any behavioral impact that could incur. A thorough literature search of various databases was conducted to gather data for the alcohol prompted gut microbiome dysbiosis. Ingenuity Pathway Analysis (IPA¹) software was then utilized to identify links between alcoholism, gut microbiome derived metabolites, and their role in behavior alterations. Overall, this meta-analysis reviews information available on the connection between alcohol induced gut microbiome dysbiosis and the resulting behavioral impact.

Differential Effects of Addictive Drugs on Sleep and Sleep Stages

Addictive drugs affect sleep both in individuals currently using drugs and in individuals who have withdrawn from drugs. In fact, sleep disturbances are reported by individuals for some drugs long after they have quit taking them and after other withdrawal symptoms have subsided. This suggests that addictive drugs and sleep share some of the same neurobiological mechanisms. Sleep researchers may be studying the neurobiology of addictive drugs without knowing it. The purpose of this survey is to summarize the effects that addictive drugs have on sleep and stages of sleep. We demonstrate that different addictive drugs have differential effects on disturbance of sleep, in general, and on specific stages of sleep either while the drug is on board or after withdrawal. Accordingly, these results are intended to encourage sleep researchers to use their knowledge of sleep mechanisms to offer researchers of addictive drugs new insights of how addictive drugs might affect brain mechanisms. Also, these results should alert researchers of addiction that treatment for drug effects needs to consider treatment for sleep disturbances as well. Treatment for addiction is rarely accompanied by treatment for sleep disturbances even though this survey demonstrates they are clearly related.

REM sleep deprivation impairs retrieval, but not reconsolidation, of methamphetamine reward memory in male rats

Susceptibility to interference can be a result of memory retrieval and reconsolidation. Given the fact that addiction develops through the neural mechanisms of learning and memory, it would not be surprising that a consolidated drug reward memory may also be susceptible to interference following retrieval/reconsolidation. Due to the critical role of sleep in memory consolidation, sleep deprivation (SD) has been shown to impair memory. Therefore, the major objective of this study was to investigate the effect of rapid eye movement (REM) sleep deprivation (RSD) on the retrieval and reconsolidation of methamphetamine (METH) reward memory in male rats. The animals were trained to acquire METH-induced CPP (2 mg/kg, i.p.). METH reward memory was then reactivated/retrieved in the drug-paired chamber during a drug-free (memory reactivation) session. A period of 48-h RSD paradigm using the multiple platform technique resulted in persistent deficits in the retrieval of METH reward memory. Nevertheless, the same protocol of RSD, which was conducted immediately after the memory reactivation, did not affect the reconsolidation of METH reward memory. Additionally, the RSD episode induced a temporary potentiation of METH-induced hyperlocomotion. Our findings would seem to suggest that sleep is involved in the retrieval, but not reconsolidation, of METH reward memory. The results may also demonstrate that RSD mimics the effects of METH on locomotor activity. The results of this study, therefore, support the idea that sleep is involved in the processing of METH reward memory which can be considered for further investigations to manage the relapse associated with drug-related memory.

Circadian melatonin profile in opium and amphetamine dependent patients: A preliminary study

Aim

The aim of this study was to investigate the relationship between opium and amphetamine dependency with the serum melatonin levels in the presence of circadian rhythm sleep disorders (CRSD).

Participants

Forty four male amphetamine-dependent and opium-dependent patients with CRSD and with more than one year substance dependency were enrolled in this study. Control group consisted of twelve healthy male subjects.

Design

The diagnoses of sleep disorders were established by a psychiatrist and were made on the basis of the criteria of ICSD-II using the patients’ sleep logs. Blood samples were drawn every 4 h through an intravenous catheter. Serum melatonin levels were assayed using an enzyme-linked immunosorbent assay (ELISA) kit. Repeated Measures Analysis of variance (ANOVA) was used to assess differences between the melatonin levels at six separate times.

Finding

The serum melatonin levels of the control subjects were significantly higher than both opium-dependent and amphetamine-dependent patients at 24:00, 4:00 and 8:00. The serum melatonin level of the opium-dependent patients were significantly lower than the amphetamine-dependent patients at 24:00 (26.9 ± 11.4 vs. 41 ± 19.4, respectively; p = 0.006) and were significantly higher than the amphetamine-dependent patients at 16:00 (12.7 ± 5.1 vs. 8.9 ± 4.1, respectively; p = 0.011).

Conclusion

This is an evidence of negative effects of substance dependence on circadian cycle of melatonin secretion among opium and amphetamine dependent patients.

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Sleep problems in substance abuse patients may be caused by dysfunction of circadian rhythm.

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High prevalence of circadian rhythm sleep disorders (CRSD) in substance dependent patients, possibly related to abnormal melatonin cycle.

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Circadian rhythm-based interventions could play an important role in the prevention and treatment of substance use disorders.

Melatonin pretreatment attenuates acute methamphetamine-induced aggression in male ICR mice

Aggression is one of the symptoms of methamphetamine (MA) use and withdrawal, which can exacerbate MA addiction and relapse. Many studies have demonstrated that poor sleep is significantly associated with aggression. Melatonin has been indicated to be effective in treating sleep disorders induced by MA, and it can also protect neuronal cells against MA-induced neurotoxicity. However, the underlying effects of melatonin on MA-reduced aggression remain unclarified. This study was designed to evaluate the effects of melatonin on acute MA-induced aggressive behavior in male ICR mice and the effects on neurotransmitters related to aggression. Fifty male ICR mice were randomly assigned to control and treatment groups pretreated with MA (3 mg/kg) or melatonin (2.5, 5, 10 mg/kg) plus MA. Aggressive behaviors were observed through isolation-induced aggression in the resident-intruder model. High-performance liquid chromatography combined with electrochemical detection (HPLC-ECD) was used to anatomize the levels of dopamine (DA) and its metabolites, 3,4-dihydroxyphenyl acetic acid (DOPAC) and homovanillic acid (HVA), and the concentrations of serotonin (5-HT) and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA), in the hippocampus involved in behavior processing. The results showed that acute MA administration decreased latency to initial attacks and thereby increased the number and total duration of attacks. Furthermore, HVA level as well as 5-HIAA and 5-HT turnover estimated by 5-HIAA/5-HT ratios declined compared to those in the vehicle group. The medium melatonin pretreatment dose (5 mg/kg) could significantly reverse acute MA-induced aggressive behavior in the form of prolonging latency to initial attacks and thereby attenuating the number of attacks and total duration of attacks. HVA and 5-HIAA levels, 5-HT turnover estimated by 5-HIAA/5-HT ratios, and DA turnover estimated by HVA/DA ratios and (DOPAC + HVA)/DA ratios were elevated compared to those in the MA group. These results indicate that the DA and 5-HT systems are involved in the processes of MA-induced aggressive behaviors and that melatonin has the capacity to reverse MA-induced aggressive behaviors.

Circadian Rhythms and Measures of CNS/Autonomic Interaction

The physiological role and relevance of the mechanisms sustaining circadian rhythms have been acknowledged. Abnormalities of the circadian and/or sleep-wakefulness cycles can result in major metabolic disorders or behavioral/professional inadequacies and stand as independent risk factors for metabolic, psychiatric, and cerebrovascular disorders and early markers of disease. Neuroimaging and clinical evidence have documented functional interactions between autonomic (ANS) and CNS structures that are described by a concept model (Central Autonomic Network) based on the brain-heart two-way interplay. The circadian rhythms of autonomic function, ANS-mediated processes, and ANS/CNS interaction appear to be sources of variability adding to a variety of environmental factors, and may become crucial when considering the ANS major role in internal environment constancy and adaptation that are fundamental to homeostasis. The CNS/ANS interaction has not yet obtained full attention and systematic investigation remains overdue.

Dopamine Signaling in Circadian Photoentrainment: Consequences of Desynchrony

Circadian rhythms, or biological oscillations of approximately 24 hours, impact almost all aspects of our lives by regulating the sleep-wake cycle, hormone release, body temperature fluctuation, and timing of food consumption. The molecular machinery governing these rhythms is similar across organisms ranging from unicellular fungi to insects, rodents, and humans. Circadian entrainment, or temporal synchrony with one's environment, is essential for survival. In mammals, the central circadian pacemaker is located in the suprachiasmatic nucleus (SCN) of the hypothalamus and mediates entrainment to environmental conditions. While the light:dark cycle is the primary environmental cue, arousal-inducing, non-photic signals such as food consumption, exercise, and social interaction are also potent synchronizers. Many of these stimuli enhance dopaminergic signaling suggesting that a cohesive circadian physiology depends on the relationship between circadian clocks and the neuronal circuits responsible for detecting salient events. Here, we review the inner workings of mammalian circadian entrainment, and describe the health consequences of circadian rhythm disruptions with an emphasis on dopamine signaling.

Psychometrics of the Self-Report Concise Associated Symptoms Tracking Scale (CAST-SR): Results From the STRIDE (CTN-0037) Study

OBJECTIVE

The self-report Concise Associated Symptoms Tracking Scale (CAST-SR) was developed to track mania, irritability, anxiety, panic, and insomnia symptoms among depressed outpatients receiving antidepressant medication. Given the overlap between these domains, depression, and stimulant use disorders, we reexamined CAST-SR psychometrics in a novel sample: individuals with stimulant use disorder receiving aerobic exercise or health education interventions.

METHODS

Using the subsample of stimulant-dependent (following DSM-IV criteria) individuals prescribed antidepressants (N = 124) from the multisite Stimulant Reduction Intervention Using Dosed Exercise (CTN-0037) trial (total sample N = 302), conducted July 2010 to February 2013, we analyzed CAST-SR data collected at the first assessment after participant's discharge from residential treatment. We also evaluated the convergent/discriminant validity of the CAST-SR with several self-report questionnaires.

RESULTS

Confirmatory factor analysis revealed a 12-item measure composed of 4 factors: irritability, anxiety, panic, and insomnia. This factor structure loaded only in participants prescribed antidepressant medication, not in those who were not prescribed antidepressants. These results replicate the original CAST-SR factor structure, except for the mania factor, which failed to load. Internal consistency was high (α = 0.92 for total scale and α = 0.78-0.89 for the 4 factors), and convergent validity was established, especially for the insomnia and irritability factors, alongside the total score with depressive symptoms, insomnia, quality of life, suicide risk, and physical health measures.

CONCLUSIONS

These results demonstrate the factor structure, reliability, and validity of the CAST-SR in a novel population of only individuals with stimulant use disorders receiving both exercise/health education interventions and antidepressant medication.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01141608.

Life stress, sense of belonging and sleep in American Indian college students

OBJECTIVES

In a sample of 90 American Indian (AI) college students (Age M(SD) = 21.47(3.02), 61.1% female), we investigated relationships between stress (perceived psychological stress and recent negative life events), sense of belonging to the university community and tribal community and sleep. We hypothesized that belonging and stress would associate with sleep.

METHODS

Participants wore a wrist accelerometer for 7 nights and answered surveys during an in-lab visit.

RESULTS

Sense of belonging to the university community associated with actigraphy-measured wake after sleep onset (WASO) (β = -.45, t(80) = -3.98, P < .001, R² change = 0.16), total sleep time (β = .30, t(80) = 2.49, P = .02, R² change = .07), sleep efficiency (β = .38, t(80) = 3.29, P = .001, R² change = .11) and subjective global sleep quality (β = -.44, t(75) = -4.82, P < .001, R² change = .15). Sense of belonging to the tribal community predicted average wake after sleep onset (β = -.29, t(80) = -2.64, P = .01, R² change = 0.08). Total negative life events in the preceding year associated with WASO (β = .24, t(80) = 2.19, P = .03, R² change = 0.05), while perceived psychological stress associated with actigraphy-measured sleep efficiency (β = -.28, t(80) = -2.25, P = .03, R² change = 0.06) and subjective global sleep quality (β = .40, t(78) = 3.94, P < .001, R² change = 0.16).

CONCLUSIONS

Stress and sense of belonging associate with sleep in AI college students. Future research should investigate whether life stress and belonging may affect health in this population by affecting patterns of sleep and investigate psychosocial resources that may moderate the relationships between stress, belonging and sleep.

Preliminary Evidence That Real World Sleep Timing and Duration are Associated With Laboratory-Assessed Alcohol Response

BACKGROUND

Sleep timing and evening chronotype have been implicated in alcohol use problems but research has yet to study them in relation to theory-driven laboratory-based measures of alcohol use disorder risk. The current study examined (i) whether chronotype, sleep timing, and/or sleep duration are associated with alcohol response (subjective stimulation, sedation, and behavioral disinhibition) and (ii) if sex and race moderate these associations.

METHODS

Adult drinkers (N = 144; 46 female participants) completed 2 counterbalanced beverage administration sessions (alcohol and nonalcohol) during which they rated stimulation/sedation and completed a cued go/no-go task. They reported bed and waketimes over 10 days.

RESULTS

Later sleep timing was associated with greater increases in alcohol stimulation, but among male and White participants only. Later sleep timing (among male participants) and greater eveningness (examined among White male participants only) were associated with greater overall stimulation on average in the alcohol session relative to the nonalcohol session, irrespective of alcohol consumption. More variable sleep duration was associated with greater increases in sedation.

CONCLUSIONS

These findings offer preliminary, but novel evidence that sleep characteristics may relate to the relative stimulating and sedating effects of alcohol, thereby influencing the risk for alcohol problems.

Gender differences in the bidirectional relationship between alcohol consumption and sleeplessness: the Tromsø study

BACKGROUND

The degree to which the relationship between alcohol use and sleeplessness is unidirectional or reciprocal is unclear due to great variation among the results of previous studies. The aim of the present study was to investigate if the relationship between alcohol use and sleeplessness is bidirectional by exploring how the change in and stability of alcohol use were related to sleeplessness, and vice versa, how the change in and stability of sleeplessness were related to alcohol use, in a longitudinal study spanning 13 years.

METHOD

Data were collected from 9941 adults who participated in two waves (T1: 1994-1995, and T2: 2007-2008) of the Tromsø Study, a Norwegian general population health study. Alcohol use was measured by questions asking about the frequency of drinking, amounts of alcohol normally consumed and the frequency of binge drinking, whereas sleeplessness was measured by one item asking about the frequency of experiencing sleeplessness. Variables representing change in and stability of consumption of alcohol and sleeplessness from T1 to T2 were created. Logistic regression analyses, stratified by gender, were used to analyze the data.

RESULTS

Men reporting stable high (OR = 2.11, p. < .001) or increasing (OR = 1.94, p. < .01) consumption of alcohol from T1 to T2 had a significantly higher risk of reporting sleeplessness at T2. Likewise, men experiencing stable (OR = 1.84, p. < .01) or increasing (OR = 1.78, p. < .001) sleeplessness from T1 to T2 had a significantly higher risk of reporting high consumption of alcohol at T2. No significant effects were detected among women.

CONCLUSION

The findings indicate a bidirectional relationship between high consumption of alcohol and sleeplessness only among men. Thus, healthcare professionals ought to be informed about the health risks associated with excessive drinking and struggling with sleeplessness, especially in men.

Circadian misalignment and weekend alcohol use in late adolescent drinkers: preliminary evidence

Alcohol use accelerates during late adolescence, predicting the development of alcohol use disorders (AUDs) and other negative outcomes. Identifying modifiable risk factors for alcohol use during this time could lead to novel prevention approaches. Burgeoning evidence suggests that sleep and circadian factors are cross-sectionally and longitudinally linked to alcohol use and problems, but more proximal relationships have been understudied. Circadian misalignment, in particular, is hypothesized to increase the risk for AUDs, but almost no published studies have included a biological measure of misalignment. In the present study, we aimed to extend existing research by assessing the relationship between adolescent circadian misalignment and alcohol use on a proximal timeframe (over two weeks) and by including three complementary measures of circadian alignment. We studied 36 healthy late (18-22 years old, 22 females) alcohol drinkers (reporting ≥1, standard drink per week over the past 30 days) over 14 days. Throughout the study, participants reported prior day's alcohol use and prior night's sleep each morning via smartphone and a secure, browser-based interface. Circadian phase was assessed via the dim light melatonin onset (DLMO) in the laboratory on two occasions (Thursday and Sunday nights) in counterbalanced order. The three measures of circadian alignment included DLMO-midsleep interval, "classic" social jet lag (weekday-weekend difference in midsleep), and "objective" social jet lag (weekday-weekend difference in DLMO). Multivariate imputation by chained equations was used to impute missing data, and Poisson regression models were used to assess associations between circadian alignment variables and weekend alcohol use. Covariates included sex, age, Thursday alcohol use, and Thursday sleep characteristics. As predicted, greater misalignment was associated with greater weekend alcohol use for two of the three alignment measures (shorter DLMO-midsleep intervals and larger weekday-weekend differences in midsleep), while larger weekday-weekend differences in DLMO were associated with less alcohol use. Notably, in contrast to expectations, the distribution of weekday-weekend differences in DLMO was nearly equally distributed between individuals advancing over the weekend and those delaying over the weekend. This unexpected finding plausibly reflects the fact that college students are not subject to the same systematically earlier weekday schedules observed in high school students and working adults. These preliminary findings support the need for larger, more definitive studies investigating the proximal relationships between circadian alignment and alcohol use among late adolescents.

Interactions between sleep duration and quality as predictors of adolescents' adjustment

OBJECTIVES

We examined interactions between adolescents' sleep duration and quality as predictors of their internalizing symptoms and externalizing behaviors. As a secondary aim, we assessed adolescent sex, race/ethnicity, and socioeconomic status (SES) as additional moderators of risk (ie, 3-way interactions among sleep duration; quality; and sex, race, or SES).

DESIGN

The study used a cross-sectional design.

SETTING

Participants were from small towns and semirural communities in Alabama.

PARTICIPANTS

The sample consisted of 235 adolescents (M_age = 15.78 years, SD = 9.60 months) and was diverse with respect to sex (54% female), race/ethnicity (32% Black/African American, 67% White), and SES.

MEASUREMENTS

Sleep duration (actual sleep minutes) was examined with actigraphs for 1 week. Adolescents reported on their subjective sleep quality, internalizing symptoms, and externalizing behavior with psychometrically sound measures.

RESULTS

Findings revealed interactions between sleep duration and sleep quality as predictors of adolescents' adjustment. Adolescents with both short sleep duration in conjunction with poor sleep quality had the highest levels of internalizing symptoms and aggressive and rule-breaking behavior. SES interacted with sleep duration and sleep quality to predict rule-breaking behavior, and the highest level of problems was observed for adolescents from lower-SES homes who had short sleep duration accompanied by poor sleep quality.

CONCLUSIONS

Findings identify the conjoint role of sleep duration and quality as predictors of adolescents' socioemotional adjustment and emphasize the importance of examining multiple sleep parameters simultaneously toward a better understanding of adaptation in adolescence.

Relationships between sleep duration and adolescent depression: a conceptual replication

OBJECTIVE

Given the growing concern about research reproducibility, we conceptually replicated a previous analysis of the relationships between adolescent sleep and mental well-being using a new dataset.

METHODS

We conceptually reproduced an earlier analysis (Sleep Health, June 2017) using baseline data from the START Study. START is a longitudinal research study designed to evaluate a natural experiment in delaying high school start times, examining the impact of sleep duration on weight change in adolescents. In both START and the previous study, school day bedtime, wake-up time, and answers to a 6-item depression subscale were self-reported using a survey administered during the school day. Logistic regression models were used to compute the association and 95% confidence intervals between the sleep variables (sleep duration, wake-up time, and bedtime) and a range of outcomes.

RESULTS

In both analyses, greater sleep duration was associated with lower odds (P < .0001) of all 6 indicators of depressive mood. Five of the 6 sleep duration point estimates from the START Study and 4 of the 6 wake-up time point estimates fell within the 95% confidence intervals from the previous analysis. However, the associations between wake-up time and outcomes differed between the 2 studies' analyses.

CONCLUSION

Our findings add strength to the evidence supporting an association between short sleep duration and depression. This issue deserves attention from school districts given the current epidemic of short sleep duration among youth and the potential impact school scheduling can have on teen sleep.

Aging circadian rhythms and cannabinoids

Numerous aspects of mammalian physiology exhibit cyclic daily patterns known as circadian rhythms. However, studies in aged humans and animals indicate that these physiological rhythms are not consistent throughout the life span. The simultaneous development of disrupted circadian rhythms and age-related impairments suggests a shared mechanism, which may be amenable to therapeutic intervention. Recently, the endocannabinoid system has emerged as a complex signaling network, which regulates numerous aspects of circadian physiology relevant to the neurobiology of aging. Agonists of cannabinoid receptor-1 (CB1) have consistently been shown to decrease neuronal activity, core body temperature, locomotion, and cognitive function. Paradoxically, several lines of evidence now suggest that very low doses of cannabinoids are beneficial in advanced age. One potential explanation for this phenomenon is that these drugs exhibit hormesis-a biphasic dose-response wherein low doses produce the opposite effects of higher doses. Therefore, it is important to determine the dose-, age-, and time-dependent effects of these substances on the regulation of circadian rhythms and other processes dysregulated in aging. This review highlights 3 fields-biological aging, circadian rhythms, and endocannabinoid signaling-to critically assess the therapeutic potential of endocannabinoid modulation in aged individuals. If the hormetic properties of exogenous cannabinoids are confirmed, we conclude that precise administration of these compounds may bidirectionally entrain central and peripheral circadian clocks and benefit multiple aspects of aging physiology.

The Relationship Between Childhood Trauma and Poor Sleep Health in Adulthood

OBJECTIVE

Childhood trauma has been related to adverse behavioral, mental, and health outcomes later in life. Sleep may be a potential mechanism through which childhood trauma is related to adverse health. The current retrospective study aimed to characterize the relationship between childhood trauma exposure and sleep health, a novel multidimensional measure of sleep.

METHODS

Participants (N = 161; mean [standard deviation] age = 59.85 [9.06] years; 67.7% female) retrospectively reported trauma exposure using the Trauma History Questionnaire. Childhood trauma was defined as the number of reported traumatic events before 18 years of age. Trauma exposure after 18 years of age and across the life-span was also recorded. Sleep health was derived both from diary- and actigraphy-assessed measures of sleep regularity, timing, efficiency, and duration, subjective sleep satisfaction, and daytime sleepiness from the Epworth Sleepiness Scale. The relationships between childhood trauma exposure and sleep health were examined using hierarchical linear regression, controlling for relevant covariates.

RESULTS

In unadjusted models, a greater number of childhood trauma exposures were associated with poorer diary- and actigraphy-measured sleep health in adulthood. After adjustment for current stress, depression history, and other sociodemographic covariates, greater childhood trauma remained significantly associated with poorer sleep health (diary: β = -0.20, ΔR = 0.032; actigraphy: β = -0.19, ΔR = 0.027). Trauma exposure after 18 years of age and across the life-span did not relate to diary- or actigraphy-based sleep health.

CONCLUSIONS

Childhood trauma may affect sleep health in adulthood. These findings align with the growing body of evidence linking childhood trauma to adverse health outcomes later in life.

The Effect of Detoxification on Sleep: How Does Sleep Quality Change during Qualified Detoxification Treatment?

Aims. Sleep disturbances are common in addiction and withdrawal. This study examined the course of sleep quality in a population of alcohol dependent patients during qualified detoxification treatment in a psychiatric hospital. Methods. The Pittsburgh Sleep Quality Index (PSQI) was administered to 77 electively admitted alcohol dependent patients hospitalized for qualified detoxification treatment. Sleep quality was measured at admission and at discharge. Results. The prevalence of bad sleep as measured by a PSQI-score > 5 was 70.1% at admission. During detoxification, male and female patients were equally affected by sleep disturbances and improvement of sleep was not significantly different between males and females. The PSQI score at admission predicted the change of the PSQI score during qualified detoxification treatment. After inpatient detoxification, sleep disturbances persisted in 59.7% of the patients. Conclusions. Contrary to our expectations, the average patient's sleep quality improved in our study after two weeks of detoxification treatment. Sleep disturbances nevertheless persisted in almost two-thirds of the patients. In the view of that finding, patients may require individual evaluation of sleep quality and insomnia-specific treatment in the course of detoxification therapy.

Risky Alcohol Consumption and Online Activity Levels

University students engage in risky patterns of alcohol consumption, which may affect their health and performance at university. This study provides a novel analysis which tracked students' interaction with online course materials over time, and examined associations between online activity and alcohol related harm (as indicated by the Alcohol Use Disorders Identification Test). Study 1 tracked 63 undergraduate psychology students in the second half of a semester and found risky drinking behaviors were marginally related to reductions in online study activity. Study 2 tracked 88 undergraduate psychology students in the first half of a semester. Risky drinking behaviors were associated with less online activity after midday. Students reporting more alcohol related harm were less likely to login between 7 pm and midnight, and between 1 am and 6 am. This study demonstrates a potential sensitivity of online activity levels to alcohol use.