Sleep disturbance as a universal risk factor for relapse in addictions to psychoactive substances

Evaluation of the Sleepy Patient: Differential Diagnosis

Excessive daytime sleepiness is defined as the inability to maintain wakefulness during waking hours, resulting in unintended lapses into sleep. It is important to distinguish sleepiness from fatigue. The evaluation of a sleep patient begins with a careful clinical assessment that includes a detailed sleep history, medical and psychiatric history, a review of medications, as well as a social and family history. Physical examination should include a general medical examination with careful attention to the upper airway and the neurologic examination. Appropriate objective testing with a polysomnogram and a multiple sleep latency test if needed will help confirm the diagnosis and direct the appropriate treatment plan.

GABAA receptor positive allosteric modulators modify the abuse-related behavioral and neurochemical effects of methamphetamine in rhesus monkeys

GABA_A receptor positive allosteric modulators (GABA_A receptor modulators) are commonly used for the treatment of insomnia. Nevertheless, the effects of these compounds on psychostimulant-induced sleep impairment are poorly understood. Because GABA_A receptor modulators have been shown to decrease the abuse-related effects of psychostimulants, the aim of the present study was to evaluate the effects of temazepam (0.3, 1.0 or 3.0 mg/kg) and eszopiclone (0.3, 1.0 or 3.0 mg/kg), two GABA_A receptor modulators, on the behavioral neuropharmacology of methamphetamine in adult rhesus macaques (n = 5). Sleep-like measures and general daytime activity were evaluated with Actiwatch monitors. Methamphetamine self-administration (0.03 mg/kg/inf) was evaluated during morning sessions. Methamphetamine-induced dopamine overflow was assessed through in vivo microdialysis targeting the nucleus accumbens. Nighttime treatment with either temazepam or eszopiclone was ineffective in improving sleep-like measures disrupted by methamphetamine self-administration. Acute pretreatment with a low dose of temazepam before self-administration sessions increased methamphetamine self-administration without affecting normal daytime home-cage activity. At a high dose, acute temazepam pretreatment decreased methamphetamine self-administration and attenuated methamphetamine-induced increases in dopamine in the nucleus accumbens, without decreasing general daytime activity. Acute eszopiclone treatment exerted no effects on methamphetamine intake or drug-induced increases in dopamine. Our study suggests that treatments based on GABA_A receptor modulators are not effective for the treatment of sleep disruption in the context of psychostimulant use. In addition, distinct GABA_A receptor modulators differentially modulated the abuse-related effects of methamphetamine, with acute treatment with the high efficacy GABA_A receptor modulator temazepam decreasing the behavioral and neurochemical effects of methamphetamine.

Daily sleep quality affects drug craving, partially through indirect associations with positive affect, in patients in treatment for nonmedical use of prescription drugs

OBJECTIVE

Sleep disturbance has been identified as a risk factor for relapse in addiction to a range of substances. The relationship between sleep quality and treatment outcome has received relatively little attention in research on nonmedical use of prescription drugs (NMUPD). This study examined the within-person association between sleep quality and craving in medically detoxified patients in residence for the treatment of NMUPD.

METHOD

Participants (n=68) provided daily reports of their sleep quality, negative affect (NA), positive affect (PA), and craving for an average of 9.36 (SD=2.99) days. Within-person associations of sleep quality and craving were examined using multilevel modeling. Within-person mediation analyses were used to evaluate the mediating roles of NA and PA in the relationship between sleep quality and craving.

RESULTS

Greater cravings were observed on days of lower than usual sleep quality (γ₁₀=-0.10, p=0.003). Thirty-one percent of the overall association between sleep quality and craving was explained by PA, such that poorer sleep quality was associated with lower PA and, in turn, lower PA was associated with greater craving. No evidence emerged for an indirect association between sleep quality and craving through NA.

CONCLUSIONS

Daily fluctuations in sleep quality were associated with fluctuations in craving, an association partially explained by the association between sleep quality and daily PA. These data encourage further research on the relationship between sleep, affect, and craving in NMUPD patients, as well as in patients with other substance use disorders.

Factors Associated with Cessation Activities amongst a Multiethnic Sample of Transit Workers

Introduction: Transit workers are a blue-collar occupational group with elevated rates of smoking despite access to free or low-cost cessation services available through their health insurance as a union-negotiated employee benefit. Little is known about the influences on cessation participation in this workforce.

Aims: The purpose of this study is to analyse the factors associated with past-year cessation activities amongst a multiethnic sample of transit workers.

Methods: Cross-sectional tobacco surveys were completed by 935 workers at an Oakland, California, USA-based public transit agency. Data from 190 current smokers (68% African American; 46% female) were analysed. Adjusted odds ratios were calculated to identify factors associated with past-year cessation activity.

Results: Approximately 55% of smokers stopped smoking for one day or longer during the past year in order to quit. Nearly half reported that the most common barrier to quitting was, ‘Not mentally ready to quit because I like smoking’. Workers in the contemplation/precontemplation stage for intention to quit were less likely to have engaged in cessation activities than those in the action/preparation stage (AOR = 0.34). Frequency of coworker encouragement for quitting was positively associated with past-year cessation activities (AOR = 3.25). Frequency of insomnia symptoms was negatively associated with cessation activity participation (AOR = 0.34).

Conclusions: Most transit workers who smoke made a past-year quit attempt. Gaining insight into factors associated with participation in cessation activities can aid worksite efforts to promote cessation and reduce tobacco-related disparities.

Sleep disturbance in substance use disorders and comorbid chronic viral infections

Sleep disruption is associated with both substance use disorders and chronic viral infections, which commonly co-occur. A greater understanding of how sleep is affected by substance abuse and comorbid chronic viral infections is needed, as fatigue, depression and other neuropsychiatric impairments caused by chronic viral infections can affect response to addiction treatment adversely.

Sleep abnormalities associated with alcohol, cannabis, cocaine, and opiate use: a comprehensive review

Sleep abnormalities are associated with acute and chronic use of addictive substances. Although sleep complaints associated with use and abstinence from addictive substances are widely recognized, familiarity with the underlying sleep abnormalities is often lacking, despite evidence that these sleep abnormalities may be recalcitrant and impede good outcomes. Substantial research has now characterized the abnormalities associated with acute and chronic use of alcohol, cannabis, cocaine, and opiates. This review summarizes this research and discusses the clinical implications of sleep abnormalities in the treatment of substance use disorders.

Actigraphy-based sleep parameters during the reinstatement of methamphetamine self-administration in rhesus monkeys

The objective of this study was to investigate nighttime activity of nonhuman primates during extinction and cue- and drug-primed reinstatement of methamphetamine self-administration. Adult rhesus monkeys (Macaca mulatta; n = 5) self-administered methamphetamine (0.01 mg/kg/injection, i.v.) under a fixed-ratio 20 schedule of reinforcement. Saline infusions were then substituted for methamphetamine and stimulus light (drug-conditioned stimulus presented during drug self-administration) withheld until subjects reached extinction criteria. Drug- and cue-induced reinstatement effects were evaluated after i.v. noncontingent priming injections of methamphetamine (0.03, 0.1, or 0.3 mg/kg). Activity-based sleep measures were evaluated with Actiwatch monitors a week before (baseline nighttime activity parameters) and throughout the protocol. Although methamphetamine self-administration did not significantly affect nighttime activity compared to baseline, sleeplike parameters were improved during extinction compared to self-administration maintenance. Priming injection of 0.1 mg/kg methamphetamine, but not 0.03 or 0.3 mg/kg, induced significant reinstatement effects. These behavioral responses were accompanied by nighttime outcomes, with increased sleep fragmentation and decreased sleep efficiency in the night following 0.1 mg/kg methamphetamine-induced reinstatement. In the absence of both drug and drug-paired cues (extinction conditions), nighttime activity decreased compared to self-administration maintenance. Additionally, effective reinstatement conditions impaired sleeplike measures. Our data indicate that the reintroduction of the stimulus light as a drug-paired cue increased nighttime activity.

Sleep Disturbance in Substance Use Disorders

This article discusses the role sleep and alertness disturbance plays in the initiation, maintenance and relapse of substance use disorders.

Possible evidence for re-regulation of HPA axis and brain reward systems over time in treatment in prescription opioid-dependent patients

OBJECTIVES

There is growing evidence for a neuroadaptive model underlying vulnerability to relapse in opioid dependence. The purpose of this study was to evaluate clinical measures hypothesized to mirror elements of allostatic dysregulation in patients dependent on prescription opioids at 2 time points after withdrawal, compared with healthy control participants.

METHODS

Recently withdrawn (n = 7) prescription opioid-dependent patients were compared with the patients in supervised residential care for 2 to 3 months (extended care; n = 7) and healthy controls (n = 7) using drug cue reactivity, affect-modulated startle response tasks, salivary cortisol, and 8 days of sleep actigraphy. Prefrontal cortex was monitored with functional near-infrared spectroscopy during the cue reactivity task.

RESULTS

Startle response results indicated reduced hedonic response to natural rewards among patients recently withdrawn from opioids relative to extended care patients. The recently withdrawn patients showed increased activation to pill stimuli in right dorsolateral prefrontal cortex relative to extended care patients. Cortisol levels were elevated among recently withdrawn patients and intermediate for extended care relative to healthy controls. Actigraphy indicated disturbed sleep between recently withdrawn patients and extended care patients; extended care patients were similar to controls. Dorsolateral prefrontal cortex activation to drug and natural reward cues, startle responses to natural reward cues, day-time cortisol levels, time in bed, and total time spent sleeping were all correlated with the number of days since last drug use (ie, time in supervised residential treatment).

CONCLUSIONS

These results suggest possible re-regulation of dysregulated hypothalamic-pituitary-adrenal axis and brain reward systems in prescription opioid-dependent patients over the drug-free period in residential treatment.

Neural plasticity in hypocretin neurons: the basis of hypocretinergic regulation of physiological and behavioral functions in animals

The neuronal system that resides in the perifornical and lateral hypothalamus (Pf/LH) and synthesizes the neuropeptide hypocretin/orexin participates in critical brain functions across species from fish to human. The hypocretin system regulates neural activity responsible for daily functions (such as sleep/wake homeostasis, energy balance, appetite, etc.) and long-term behavioral changes (such as reward seeking and addiction, stress response, etc.) in animals. The most recent evidence suggests that the hypocretin system undergoes substantial plastic changes in response to both daily fluctuations (such as food intake and sleep-wake regulation) and long-term changes (such as cocaine seeking) in neuronal activity in the brain. The understanding of these changes in the hypocretin system is essential in addressing the role of the hypocretin system in normal physiological functions and pathological conditions in animals and humans. In this review, the evidence demonstrating that neural plasticity occurs in hypocretin-containing neurons in the Pf/LH will be presented and possible physiological, behavioral, and mental health implications of these findings will be discussed.

The Effects of Lithium Carbonate Supplemented with Nitrazepam on Sleep Disturbance during Cannabis Abstinence

STUDY OBJECTIVE

Sleep disturbance is a hallmark feature of cannabis withdrawal. In this study we explored the effects of lithium treatment supplemented with nitrazepam on objective and subjective measures of sleep quality during inpatient cannabis withdrawal.

METHODS

Treatment-seeking cannabis-dependent adults (n = 38) were admitted for 8 days to an inpatient withdrawal unit and randomized to either oral lithium (500 mg) or placebo, twice daily in a double-blind RCT. Restricted nitrazepam (10 mg) was available on demand (in response to poor sleep) on any 3 of the 7 nights. Dependent outcome measures for analysis included repeated daily objective actigraphy and subjective sleep measures throughout the 8 day detox, subjective cannabis withdrawal ratings, and detoxification completion rates.

RESULTS

Based on actigraphy, lithium resulted in less fragmented sleep compared to placebo (p = 0.04), but no other objective measures were improved by lithium. Of the subjective measures, only nightmares were suppressed by lithium (p = 0.04). Lithium did not have a significant impact on the use of nitrazepam. Sleep bout length (p < 0.0001), sleep efficiency (p < 0.0001), and sleep fragmentation (p = 0.05) were improved on nights in which nitrazepam was used. In contrast, only night sweats improved with nitrazepam from the subjective measures (p = 0.04). A Cox regression with daily repeated measures of sleep efficiency averaged across all people in the study a predictor suggests that a one-unit increase in sleep efficiency (the ratio of total sleep time to the total time in bed expressed as a percentage) resulted in a 14.6% increase in retention in treatment (p = 0.008, Exp(B) = 0.854, 95% CI = 0.759-0.960). None of the other sleep measures, nor use of lithium or nitrazepam were significantly associated with retention in treatment.

CONCLUSIONS

Lithium seems to have only limited efficacy on sleep disturbance in cannabis withdrawal. However the nitrazepam improved several actigraphy measures of sleep disturbance, warranting further investigation. Discord between objective and subjective sleep indices suggest caution in evaluating treatment interventions with self-report sleep data only.

Pedunculopontine arousal system physiology-Effects of psychostimulant abuse

This review describes the interactions between the pedunculopontine nucleus (PPN), the ventral tegmental area (VTA), and the thalamocortical system. Experiments using modulators of cholinergic receptors in the PPN clarified its role on psychostimulant-induced locomotion. PPN activation was found to be involved in the animal’s voluntary search for psychostimulants. Every PPN neuron is known to generate gamma band oscillations. Voltage-gated calcium channels are key elements in the generation and maintenance of gamma band activity of PPN neurons. Calcium channels are also key elements mediating psychostimulant-induced alterations in the thalamic targets of PPN output. Thus, the PPN is a key substrate for maintaining arousal and REM sleep, but also in modulating psychostimulant self-administration.

Reversal of the sleep-wake cycle by heroin self-administration in rats

The goal of this study was to examine how heroin self-administration, abstinence, and extinction/reinstatement affect circadian sleep-wake cycles and the associated sleep architecture. We used electroencephalography (EEG) and electromyography (EMG) to measure sleep patterns in male Sprague-Dawley rats over 16 trials of heroin self-administration (acquisition), 14 days of abstinence, and a single day of extinction and drug-induced reinstatement. Rats self-administering heroin showed evidence of reversed (diurnal) patterns of wakefulness, non-rapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep throughout acquisition. During abstinence, their wake and NREM sleep patterns were immediately restored to the normal nocturnal distribution. REM patterns remained inverted for the first 3-6 days of abstinence in heroin self-administering rats. The single extinction/reinstatement test was without effect. These data suggest that heroin may have the ability to affect circadian distribution of sleep and wakefulness, either indirectly, where animals shift their sleep-wake cycle to allow for drug taking, or directly, through wake-promoting actions or actions at circadian oscillators in the brain.

Slow-wave disruption enhances the accessibility of positive memory traces

The purpose of this study was to explore the effects of slow-wave disruption on positive and negative word recognition in a sample of healthy control participants and those with major depressive disorder. Prior to sleep, participants learned a set of emotional and neutral words during an encoding task by responding whether or not the word described them. Following baseline sleep, participants underwent one night of selective slow-wave disruption by auditory stimuli. Accuracy and reaction time to a recognition word set, including both positive and negative words, was assessed in the morning. Repeated-measures ANOVA revealed a significant interaction between word valence and condition, with positive words recognized significantly faster than negative words after disruption, in only healthy control participants. There were no significant results in those with major depressive disorder, or with regard to accuracy. These results may add to the increasing body of literature suggesting a hedonic bias to positive stimuli following sleep disruption.

The implications of sleep disruption for cognitive and affective processing in methamphetamine abuse

Sleep is disrupted during active use of methamphetamine (MA), during withdrawal from the drug, and during abstinence from its use. However, relatively little is known about possible mediatory functions of disrupted sleep in the emergence, manifestation, and maintenance of cognitive and affective symptoms of MA abuse. We hypothesise that sleep functions as a mediator for stimulant drug effects. Specifically, we propose that objectively-measured sleep parameters can be used to explain some of the variability in the experience and presentation of memory deficits and emotion dysregulation in MA abusers. After describing how important healthy sleep is to unimpaired cognitive and affective functioning, we review literature describing how sleep is disrupted in MA abuse. Then, we provide a conceptual framework for our hypothesis by explaining the relationship between MA abuse, sleep disruption, memory deficits, emotion dysregulation, and changes in reward-related brain networks. We conclude by discussing implications of the hypothesis for research and treatment.

Work Predictors of Lapse in Patients under Treatment of Methadone Maintenance Therapy

BACKGROUND

Addiction to narcotics ‎can cause serious problems and ‎monetary losses. Therapeutic ‎success can be predicted ‎through identifying lapse risk ‎factors.‎

OBJECTIVE

Determining Job Risk ‎Factor of Lapse.‎

METHODS

This was a cross ‎sectional study on 351 addicts ‎visiting five methadone clinics. A ‎Data collection sheet consisting ‎of questions on demographic ‎and job information was filled up ‎through direct interviews. ‎Information relating to lapse in ‎the first month was analyzed.‎

RESULTS

The mean (SD) age of ‎the participants was 40(12) ‎years; of them, 74% were ‎employed, of whom 34% had ‎lapsed. A relationship was ‎noticed between education ‎qualification (secondary school ‎compared with higher and lower ‎education) and lapse (p = .04), ‎and also between type of drug ‎abuse (amphetamine) and lapse ‎‎(p = .001).‎

CONCLUSION

‎ ‏ ‏‎ Lapse was more ‎dependent on type of drug abused, ‎and employment had a protective role, ‎with no correlation with the type of ‎job and other job conditions. Non-‎work factors mediated/suppressed the ‎role of occupational conditions.‎.

Clinical Efficacy of Traditional Chinese Medicine, Suan Zao Ren Tang, for Sleep Disturbance during Methadone Maintenance: A Randomized, Double-Blind, Placebo-Controlled Trial

Methadone maintenance therapy is an effective treatment for opiate dependence, but more than three-quarters of persons receiving the treatment report sleep quality disturbances. In this double-blind, randomized, controlled trial, we recruited 90 individuals receiving methadone for at least one month who reported sleep disturbances and had Pittsburgh Sleep Quality Index (PSQI) scores > 5. The purpose of this study was to determine whether Suan Zao Ren Tang, one of the most commonly prescribed traditional Chinese medications for treatment of insomnia, improves subjective sleep among methadone-maintained persons with disturbed sleep quality. Ninety patients were randomly assigned to intervention group (n = 45) and placebo group (n = 45), and all participants were analyzed. Compared with placebo treatment, Suan Zao Ren Tang treatment for four weeks produced a statistically significant improvement in the mean total PSQI scores (P = 0.007) and average sleep efficiency (P = 0.017). All adverse events (e.g., lethargy, diarrhea, and dizziness) were mild in severity. Suan Zao Ren Tang is effective for improving sleep quality and sleep efficiency among methadone-maintained patients with sleep complaints.

Brain pathways to recovery from alcohol dependence

This article highlights the research presentations at the satellite symposium on "Brain Pathways to Recovery from Alcohol Dependence" held at the 2013 Society for Neuroscience Annual Meeting. The purpose of this symposium was to provide an up to date overview of research efforts focusing on understanding brain mechanisms that contribute to recovery from alcohol dependence. A panel of scientists from the alcohol and addiction research field presented their insights and perspectives on brain mechanisms that may underlie both recovery and lack of recovery from alcohol dependence. The four sessions of the symposium encompassed multilevel studies exploring mechanisms underlying relapse and craving associated with sustained alcohol abstinence, cognitive function deficit and recovery, and translational studies on preventing relapse and promoting recovery. Gaps in our knowledge and research opportunities were also discussed.

Cardiac autonomic function during sleep: effects of alcohol dependence and evidence of partial recovery with abstinence

Chronic alcoholism is associated with the development of cardiac and peripheral autonomic nervous system (ANS) pathology. The aim of the present study was to evaluate the extent to which recovery in ANS function could be demonstrated over the first 4 months of abstinence. Fifteen alcoholics (7 women) were studied on three occasions: within a month of detoxification, at approximately 2 months post-detox, and at 4 months post-detox. Thirteen control subjects (6 women) were also studied on three occasions with inter-study intervals matching those of the alcoholics. Six alcoholics relapsed, 48.7 ± 27.9 days following the initial PSG session. ANS function was assessed in the first part of stable non-rapid eye movement sleep. Frequency-domain power spectral analysis of heart rate variability (HRV) produced variables including: heart rate (HR), total power (TP; an index representing total HR variability), High Frequency power (HFa; an index reflecting cardiac vagal modulation), HF proportion of total power (HFprop sympathovagal balance), and HF peak frequency (HFpf; an index reflecting respiration rate). Overall, high total and high frequency variability and low sympathovagal balance and myocardial contractility are considered as desired conditions to promote cardiovascular health. At initial assessment, alcoholics had a higher HR (p < 0.001) and respiratory rate (p < 0.01), and lower vagal activity (HFa; p < 0.01) than controls. Alcoholics showed evidence of recovery in HR (p = 0.039) and HFa (p = 0.031) with 4 months of abstinence. Alcoholics with higher TP at the initial visit showed a greater improvement in TP from the initial to the 4 month follow-up session (r = 0.75, p < 0.05). Alcoholics showed substantial recovery in HR and vagal modulation of HRV with 4 months of abstinence, with evidence that the extent of recovery in HRV may be partially determined by the extent of alcohol dependence-related insult to the cardiac ANS system. These data support other studies showing recovery in a number of ANS, central nervous system, and behavioral domains with abstinence, even in those with long-term dependence.

Alcohol and lithium have opposing effects on the period and phase of the behavioral free-running activity rhythm

Bipolar patients have a high prevalence of comorbid alcohol use and abuse disorders, while chronic alcohol drinking may increase the presence and severity of certain symptoms of bipolar disorder. As such, there may be many individuals that are prescribed lithium to alleviate the manic symptoms of bipolar disorder, but also drink alcohol concurrently. In addition, both alcoholics and individuals with bipolar disorder often exhibit disruptions to their sleep-wake cycles and other circadian rhythms. Interestingly, both ethanol and lithium are known to alter both the period and the phase of free-running rhythms in mammals. While lithium is known to lengthen the period, ethanol seems to shorten the period and attenuate the responses to acute light pulses. Therefore, the present study aimed to determine whether ethanol and lithium have opposing effects on the circadian pacemaker when administered together. C57BL/6J mice were provided drinking solutions containing lithium, alcohol, or both, and their free-running rhythms along with their response to photic phase shifts were investigated. Mice treated with lithium displayed period lengthening, which was almost completely negated when ethanol was added. Moreover, ethanol significantly attenuated light-induced phase delays while the addition of lithium partially restored this response. These results indicate that alcohol and lithium have opposing effects on behavioral circadian rhythms. Individuals with bipolar disorder who are prescribed lithium and who drink alcohol might be inadvertently altering their sleep and circadian cycles, which may exacerbate their symptoms.

Alcohol disrupts sleep homeostasis

Alcohol is a potent somnogen and one of the most commonly used "over the counter" sleep aids. In healthy non-alcoholics, acute alcohol decreases sleep latency, consolidates and increases the quality (delta power) and quantity of NREM sleep during the first half of the night. However, sleep is disrupted during the second half. Alcoholics, both during drinking periods and during abstinences, suffer from a multitude of sleep disruptions manifested by profound insomnia, excessive daytime sleepiness, and altered sleep architecture. Furthermore, subjective and objective indicators of sleep disturbances are predictors of relapse. Finally, within the USA, it is estimated that societal costs of alcohol-related sleep disorders exceeds $18 billion. Thus, although alcohol-associated sleep problems have significant economic and clinical consequences, very little is known about how and where alcohol acts to affect sleep. In this review, we have described our attempts to unravel the mechanism of alcohol-induced sleep disruptions. We have conducted a series of experiments using two different species, rats and mice, as animal models. We performed microdialysis, immunohistochemical, pharmacological, sleep deprivation and lesion studies which suggest that the sleep-promoting effects of alcohol may be mediated via alcohol's action on the mediators of sleep homeostasis: adenosine (AD) and the wake-promoting cholinergic neurons of the basal forebrain (BF). Alcohol, via its action on AD uptake, increases extracellular AD resulting in the inhibition of BF wake-promoting neurons. Since binge alcohol consumption is a highly prevalent pattern of alcohol consumption and disrupts sleep, we examined the effects of binge drinking on sleep-wakefulness. Our results suggest that disrupted sleep homeostasis may be the primary cause of sleep disruption observed following binge drinking. Finally, we have also shown that sleep disruptions observed during acute withdrawal, are caused due to impaired sleep homeostasis. In conclusion, we suggest that alcohol may disrupt sleep homeostasis to cause sleep disruptions.

Sleeping problems in Chinese illicit drug dependent subjects

BACKGROUND

Illicit drug use/dependence has been recognized as a major problem. Clinical studies demonstrate that poor sleep quality is associated with increased frequency of drug use and relapse. However, few studies have addressed the issue of sleep quality among illicit drug dependent subjects.

METHODS

This cross-sectional study explored sleep quality in drug dependent subjects in China. We studied 2178 illicit drug dependent subjects from drug rehabilitation centres in Changsha and 2236 non-drug-using subjects, all of whom completed the self-report Pittsburgh Sleep Quality Index (PSQI).

RESULTS

We found that the prevalence of sleep disturbance was much higher in drug users (68.5%, PSQI >5; specifically, 80.24% in heroin users, 54.16% in methamphetamine users and 81.98% in ketamine users with PSQI >5) than non-users (26.4%, PSQI >5). Drug users had approximately twice the sleep latency than nondrug users (37.7 minutes V.S 18.4 minutes). Although drug users and non-users reported similar sleep duration (about 7.4 hours), drug users showed poorer subjective sleep quality and habitual sleep efficiency. They reported more sleep disturbance and need for sleep medications, more daytime dysfunction and poorer subjective sleep quality compared with nondrug users. The total PSQI score positively correlated with the duration of drug use (rp = 0.164, p < 0.001). We also found a link between sleep problems and cigarette smoking, alcohol drinking, and duration of drug use.

CONCLUSIONS

Poor sleep quality is common among illicit drug dependent subjects. Long-term substance users had more sleep problems. Future research aiming at quantifying the benefits of treatment interventions should not neglect the influence of sleep problems. Gaining more insight into the impact of sleep quality on the addiction treatment could also help to target future intervention measures more effectively.

Sleep disturbances and pain among individuals with prescription opioid dependence

BACKGROUND

Poor sleep quality has been observed in individuals with substance use disorders and is often a trigger for relapse. To date, little research has investigated sleep quality among individuals with prescription opioid (PO) dependence. The present study aimed to address this gap in the literature by examining subjective and objective sleep disturbances among PO dependent individuals.

METHODS

Subjects were 68 non-treatment seeking individuals (33 PO dependent, 35 healthy controls). Subjective sleep was assessed with the Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI). Subjects were admitted for an overnight inpatient hospital stay during which objective sleep data was collected using an actigraphy device. Self-report pain was measured with the Brief Pain Inventory.

RESULTS

Significant group differences in subjective sleep quality were revealed in the PSQI (p<0.01) and ISI (p<0.01). Poor sleep quality (i.e., PSQI total score>5) was identified in 80.6% of the PO group, as compared to 8.8% of the control group (p<.001). Significant group differences in sleep quality were identified in five of six actigraphy variables: total time asleep, sleep efficiency, latency of onset of sleep, total time awake and time mobile. Furthermore, significant associations between pain severity and sleep quality were observed.

CONCLUSIONS

Results indicate high rates of sleep impairment and poor sleep quality among PO dependent individuals. Pain severity was significantly correlated with sleep quality. Although preliminary, the findings highlight the importance of assessing and treating sleep disturbances, as well as pain, among patients with PO dependence.

Adenosinergic regulation of striatal clock gene expression and ethanol intake during constant light

Circadian rhythm and sleep disruptions occur frequently in individuals with alcohol use disorders (AUD) and present significant barriers to treatment. Recently, a variant of adenosine transporter, equilibrative nucleoside transporter 1 (ENT1), was associated with the co-occurrence of sleep problems and AUD. We have previously shown that mice lacking ENT1 (ENT1 KO) have reduced adenosine levels in the striatum and drink more alcohol compared with wild types (WT). However, it is unknown whether ENT1 deletion disrupts circadian rhythms, which may contribute to alcohol preference in ENT1 KO mice. Here we used these mice to determine whether endogenous adenosine regulates circadian genetic and behavioral rhythms and influences alcohol intake during chronodisruption. We examined circadian locomotor activity in ENT1 KO vs WT littermates and found that ENT1 KO mice were both active earlier and hyperactive compared with WT mice at night. We used real-time PCR and immunohistochemistry to estimate striatal clock gene levels and found that PER2 expression in the striatum was blunted by ENT1 deletion or A2A receptor (A2AR) antagonism. Next, we exposed ENT1 KO and WT mice to constant light (LL) and found further elevation in ethanol intake in ENT1 KO, but not in WT mice, supporting the notion that circadian dysfunction may contribute to increased alcohol intake in ENT1 KO mice. Finally, we showed that A2AR agonist administration normalized PER1 and PER2 expression and circadian locomotor activity in ENT1 KO mice. Together, our results demonstrate that adenosine signaling regulates cellular and behavioral circadian timing and influences alcohol intake during chronodisruption.

Interactions between disordered sleep, post-traumatic stress disorder, and substance use disorders

Disordered sleep is associated with a number of adverse health consequences and is an integral component of many psychiatric disorders. Rates of substance use disorders (SUDs) are markedly higher among individuals with post-traumatic stress disorder (PTSD), and this relationship may be partly mediated by disturbed sleep. Sleep disturbances (e.g. insomnia, daytime sleepiness, vivid nightmares) are hallmark features of PTSD and there is evidence that individuals with PTSD engage in substance use as a means of coping with these symptoms. However, prolonged substance use can lead to more severe sleep disturbances due to the development of tolerance and withdrawal. Behavioural or pharmacological treatment of disordered sleep is associated with improved daytime symptoms and psychosocial functioning among individuals who have developed PTSD. Initial research also suggests that improving sleep could be similarly beneficial in reducing coping oriented substance use and preventing relapse among those seeking treatment for SUDs. Together, these findings suggest that ameliorating sleep disturbance among at-risk individuals would be a viable target for the prevention and treatment of PTSD and associated SUDs, but prospective research is needed to examine this hypothesis. Enhanced understanding of the interrelation between sleep, PTSD, and SUDs may yield novel prevention and intervention approaches for these costly, prevalent and frequently co-occurring disorders.

Chronic sleep restriction disrupts sleep homeostasis and behavioral sensitivity to alcohol by reducing the extracellular accumulation of adenosine

Sleep impairments are comorbid with a variety of neurological and psychiatric disorders including depression, epilepsy, and alcohol abuse. Despite the prevalence of these disorders, the cellular mechanisms underlying the interaction between sleep disruption and behavior remain poorly understood. In this study, the impact of chronic sleep loss on sleep homeostasis was examined in C57BL/6J mice following 3 d of sleep restriction. The electroencephalographic power of slow-wave activity (SWA; 0.5-4 Hz) in nonrapid eye movement (NREM) sleep and adenosine tone were measured during and after sleep restriction, and following subsequent acute sleep deprivation. During the first day of sleep restriction, SWA and adenosine tone increased, indicating a homeostatic response to sleep loss. On subsequent days, SWA declined, and this was accompanied by a corresponding reduction in adenosine tone caused by a loss of one source of extracellular adenosine. Furthermore, the response to acute sleep deprivation (6 h) was significantly attenuated in sleep-restricted mice. These effects were long-lasting with reduced SWA and adenosine tone persisting for at least 2 weeks. To investigate the behavioral consequences of chronic sleep restriction, sensitivity to the motor-impairing effects of alcohol was also examined. Sleep-restricted mice were significantly less sensitive to alcohol when tested 24 h after sleep restriction, an effect that persisted for 4 weeks. Intracerebroventricular infusion of an adenosine A1 receptor antagonist produced a similar decrease in sensitivity to alcohol. These results suggest that chronic sleep restriction induces a sustained impairment in adenosine-regulated sleep homeostasis and consequentially impacts the response to alcohol.

Role of adenosine and the orexinergic perifornical hypothalamus in sleep-promoting effects of ethanol

STUDY OBJECTIVES

Strong clinical and preclinical evidence suggests that acute ethanol promotes sleep. However, very little is known about how and where ethanol acts to promote sleep. We hypothesized that ethanol may induce sleep by increasing extracellular levels of adenosine and inhibiting orexin neurons in the perifornical hypothalamus.

DESIGN

Experiments 1 and 2: Within-Subject Design; Experiment 3: Between-Subject Design.

SETTING

N/A.

PATIENTS OR PARTICIPANTS

N/A.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Using adult male Sprague-Dawley rats as our animal model, we performed three experiments to test our hypothesis. Our first experiment examined the effect of A1 receptor blockade in the orexinergic perifornical hypothalamus on sleep- promoting effects of ethanol. Bilateral microinjection of the selective A1 receptor antagonist 1,3-dipropyl-8-phenylxanthine (500 μM; 250 nL/side) into orexinergic perifornical hypothalamus significantly reduced nonrapid eye movement sleep with a concomitant increase in wakefulness, suggesting that blockade of adenosine A1 receptor attenuates ethanol-induced sleep promotion. Our second experiment examined adenosine release in the orexinergic perifornical hypothalamus during local ethanol infusion. Local infusion of pharmacologically relevant doses of ethanol significantly and dose-dependently increased adenosine release. Our final experiment used c-Fos immunohistochemistry to examine the effects of ethanol on the activation of orexin neurons. Acute ethanol exposure significantly reduced the number of orexin neurons containing c-Fos, suggesting an inhibition of orexin neurons after ethanol intake.

CONCLUSIONS

Based on our results, we believe that ethanol promotes sleep by increasing adenosine in the orexinergic perifornical hypothalamus, resulting in A1 receptor-mediated inhibition of orexin neurons.

The role of sleep in emotional brain function

Rapidly emerging evidence continues to describe an intimate and causal relationship between sleep and emotional brain function. These findings are mirrored by long-standing clinical observations demonstrating that nearly all mood and anxiety disorders co-occur with one or more sleep abnormalities. This review aims to (a) provide a synthesis of recent findings describing the emotional brain and behavioral benefits triggered by sleep, and conversely, the detrimental impairments following a lack of sleep; (b) outline a proposed framework in which sleep, and specifically rapid-eye movement (REM) sleep, supports a process of affective brain homeostasis, optimally preparing the organism for next-day social and emotional functioning; and (c) describe how this hypothesized framework can explain the prevalent relationships between sleep and psychiatric disorders, with a particular focus on posttraumatic stress disorder and major depression.

Adenosine and glutamate in neuroglial interaction: implications for circadian disorders and alcoholism

Recent studies have demonstrated that the function of glia is not restricted to the support of neuronal function. In fact, astrocytes are essential for neuronal activity in the brain and play an important role in the regulation of complex behavior. Astrocytes actively participate in synapse formation and brain information processing by releasing and uptaking glutamate, D-serine, adenosine 5'-triphosphate (ATP), and adenosine. In the central nervous system, adenosine-mediated neuronal activity modulates the actions of other neurotransmitter systems. Adenosinergic fine-tuning of the glutamate system in particular has been shown to regulate circadian rhythmicity and sleep, as well as alcohol-related behavior and drinking. Adenosine gates both photic (light-induced) glutamatergic and nonphotic (alerting) input to the circadian clock located in the suprachiasmatic nucleus of the hypothalamus. Astrocytic, SNARE-mediated ATP release provides the extracellular adenosine that drives homeostatic sleep. Acute ethanol increases extracellular adenosine, which mediates the ataxic and hypnotic/sedative effects of alcohol, while chronic ethanol leads to downregulated adenosine signaling that underlies insomnia, a major predictor of relapse. Studies using mice lacking the equilibrative nucleoside transporter 1 have illuminated how adenosine functions through neuroglial interactions involving glutamate uptake transporter GLT-1 [referred to as excitatory amino acid transporter 2 (EAAT2) in human] and possibly water channel aquaporin 4 to regulate ethanol sensitivity, reward-related motivational processes, and alcohol intake.

Pathological gambling, problem gambling and sleep complaints: an analysis of the National Comorbidity Survey: Replication (NCS-R)

The purpose of this study is to investigate the relationship between sleep disturbances and gambling behavior. Data from the National Comorbidity Survey-Replication (NCS-R) was used to examine the relationship between three specific sleep complaints (difficulty initiating sleep [DIS], difficulty maintaining sleep [DMS], and early morning awakening [EMA]) and gambling behavior. Bivariate logistic regression models were used to control for potentially confounding psychiatric disorders and age. Almost half of respondents with problem gambling behavior (45.9%) and two thirds (67.7%) of respondents with pathological gambling behavior reported at least one sleep compliant. Compared to respondents with no gambling pathology, respondents with pathological gambling were significantly more likely to report at least one sleep complaint (Adjusted Odds Ratio [AOR] = 3.444, 95% CI = 1.538-7.713), to report all sleep complaints (AOR = 3.449, 95% CI = 1.503-7.914), and to report any individual complaint (DIS: OR = 2.300, 95% CI = 1.069-4.946; DMS: AOR = 4.604, 95% CI = 2.093-10.129; EMA: AOR = 3.968, 95% CI = 1.856-8.481). The relationship between problem gambling and sleep complaints were more modest (any sleep complaint: AOR = 1.794, 95% CI = 1.142-2.818; all three sleep complaints: AOR = 2.144, 95% CI = 1.169-3.931; DIS: AOR = 1.961, 95% CI = 1.204-3.194; DMS: AOR = 1.551, 95% CI = 0.951-2.529; EMA: AOR = 1.796, 95% CI = 1.099-2.935). Given the individual and societal ramifications linked with the presence of sleep problems, this study presents another health-related repercussion associated with gambling pathology rarely discussed in the literature.

Integrating a Behavioural Sleep Intervention into Smoking Cessation Treatment for Smokers with Insomnia: A Randomised Pilot Study

INTRODUCTION

Sleep disturbance is common among cigarette smokers and predicts smoking cessation failure.

AIMS

The purpose of this study was to conduct a pilot test of whether provision of a sleep intervention might bolster smoking cessation outcomes among this vulnerable group.

METHODS

Smokers with insomnia (N = 19) seeking smoking cessation treatment were randomly assigned to receive 8 sessions over 10 weeks of either: (1) cognitive-behavioural therapy for insomnia + smoking cessation counselling (CBT-I+SC; n = 9) or (2) smoking cessation counselling alone (SC; n = 10). Counselling commenced 4 weeks prior to a scheduled quit date, and nicotine patch therapy was also provided for 6 weeks starting on the quit date.

RESULTS

There was no significant effect of counselling condition on smoking cessation outcomes. Most participants had difficulty initiating and maintaining smoking abstinence in that 7-day point prevalence abstinence rates at end of treatment (CBT-I+SC: 1/7, 14%; SC: 2/10, 20%) and follow-up (CBT-I+SC: 1/7, 14%; SC: 0/10, 0%) were low for both conditions. CBT-I+SC participants reported improvements in sleep efficiency, quality, duration and insomnia symptoms. Sleep changes were not associated with the likelihood of achieving smoking abstinence.

CONCLUSIONS

This randomised pilot study suggests that behavioural interventions may improve sleep among smokers with insomnia, but a larger sample is needed to replicate this finding and evaluate whether these changes facilitate smoking cessation.

Ethosuximide reduces ethanol withdrawal-mediated disruptions in sleep-related EEG patterns

BACKGROUND

Chronic ethanol (EtOH) leads to disruptions in resting electroencephalogram (EEG) activity and in sleep patterns that can persist into the withdrawal period. These disruptions have been suggested to be predictors of relapse. The thalamus is a key structure involved in both normal brain oscillations, such as sleep-related oscillations, and abnormal rhythms found in disorders such as epilepsy and Parkinson's disease. Previously, we have shown progressive changes in mouse thalamic T-type Ca channels during chronic intermittent EtOH exposures that occurred in parallel with alterations in theta (4 to 8 Hz) EEG patterns.

METHODS

Two groups of 8-week-old male C57BL/6 mice were implanted with wireless EEG/electromyogram (EMG) telemetry and subjected to 4 weeks of chronic, intermittent EtOH vapor exposure and withdrawal. During the week after the final withdrawal, mice were administered ethosuximide (ETX; 200 mg/kg) or saline. EEG data were analyzed via discrete Fourier transform, and sleep-scored for further analysis.

RESULTS

Chronic intermittent EtOH exposure produced changes in the diurnal rhythms of the delta (0.5 to 4 Hz) and theta bands that persisted into a subsequent week of sustained withdrawal. These disruptions were restored with the T-channel blocker ETX. Repeated EtOH exposures preferentially increased the relative proportion of lower frequency power (delta and theta), whereas higher frequencies (8 to 24 Hz) were decreased. The EtOH-induced decreases in relative power for the higher frequencies continued into the sustained withdrawal week for both groups. Increases in absolute delta and theta power were observed in averaged nonrapid eye movement and rapid eye movement sleep spectral data during withdrawal in ETX-treated animals, suggesting increased sleep intensity.

CONCLUSIONS

These results suggest that persistent alterations in delta and theta EEG rhythms during withdrawal from chronic intermittent EtOH exposure can be ameliorated with ETX and that this treatment might also increase sleep intensity during withdrawal.

BAP updated guidelines: evidence-based guidelines for the pharmacological management of substance abuse, harmful use, addiction and comorbidity: recommendations from BAP

The British Association for Psychopharmacology guidelines for the treatment of substance abuse, harmful use, addiction and comorbidity with psychiatric disorders primarily focus on their pharmacological management. They are based explicitly on the available evidence and presented as recommendations to aid clinical decision making for practitioners alongside a detailed review of the evidence. A consensus meeting, involving experts in the treatment of these disorders, reviewed key areas and considered the strength of the evidence and clinical implications. The guidelines were drawn up after feedback from participants. The guidelines primarily cover the pharmacological management of withdrawal, short- and long-term substitution, maintenance of abstinence and prevention of complications, where appropriate, for substance abuse or harmful use or addiction as well management in pregnancy, comorbidity with psychiatric disorders and in younger and older people.

GABRA2 and KIBRA genotypes predict early relapse to substance use

BACKGROUND

Numerous single nucleotide polymorphisms (SNPs) within different genes have been associated with alcohol and drug involvement or known risk factors for involvement, such as impaired cognitive control. The ability of these SNPs to predict re-involvement, defined here as abstinence failure during treatment, has not been thoroughly tested.

METHODS

We studied a small sample (n=146; 49% female) of residential substance abuse treatment program patients who had maintained 2-6 months of abstinence. They were followed for 4 months thereafter for the purpose of counting days until the first abstinence violation. The analysis used logistic and Cox regression methods to evaluate the contributions of age; sex; number of intake alcohol, drug use, and depression symptoms; and either GABRA2, CHRM2, ANKK1, BDNF, or KIBRA SNP genotypes to outcome.

RESULTS

GABRA2 and KIBRA genotypes, as well as the number of intake drug abuse problems and a younger age, were associated with an increased risk of relapse. Importantly, these genotypes were found to add value to relapse prediction: the χ(2) statistic evaluating their residual contribution, after age and the number of previous drug use problems were entered, was significant.

CONCLUSIONS

Genetic analyses may add value to outcome prediction. Future studies should evaluate the sensitivity and specificity of GABRA2 and KIBRA genotypes for this purpose in other racial/ethnic groups and treatment settings.

Sleep and gambling severity in a community sample of gamblers

Although sleep has been extensively studied in substance related disorders, it has yet to be examined as thoroughly in gambling-related disorders. The purpose of this study is to examine the relationship between gambling severity and sleep disturbances in a sample of non-treatment seeking gamblers (N = 96) using the Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). Mean ESS scores for recreational, problem, and pathological gamblers were 4.13, 5.81, and 8.69, respectively, with a significant difference between pathological gamblers and both problem (P = .007) and recreational gamblers (P < .001). Mean PSQI scores for recreational, problem, and pathological gamblers were 3.35, 5.30, and 5.44, respectively, with a significant difference in sleep quality between recreational and problem gamblers (P = .018), as well as recreational and pathological gamblers (P = .008). As the first study to use objective sleep measures, these findings will not only increase awareness of this relationship, but also provide a foundation on which others can investigate the benefits of screening and adjunct treatment for sleep disorders in the gambling population.

Prevalence and correlates of insomnia in a polish sample of alcohol-dependent patients

BACKGROUND

Insomnia is an important symptom in alcohol-dependent patients because it may persist despite abstinence and predispose to relapse to drinking. The goal of the present study was to evaluate the prevalence and clinical correlates of insomnia in a sample of 302 alcohol-dependent patients admitted to treatment programs in Poland.

METHODS

Participants were mostly men (73.8%) with a mean (SD) age of 43.5 (9.7) years. Insomnia in the past 1 month was assessed using a total score of 6 or higher on the Athens Insomnia Scale.

RESULTS

Insomnia affected 62.9% of patients, and delayed sleep induction was the most common subtype. Insomnia was associated in bivariate analyses with less education, inadequate finances, problem drinking at an earlier age of onset, drinking frequency and quantity, drinking-related consequences, severity of alcohol and nicotine dependence, psychiatric and physical severity, and a childhood history of sexual or physical abuse (p < 0.05). Logistic regression analysis showed that mental and physical health status, severity of alcohol dependence, number of drinking days in the past 3 months, and childhood abuse were independent predictors of insomnia, explaining approximately 30 to 40% of the variance.

CONCLUSIONS

More than 60% of alcohol-dependent patients in a Polish sample screened positive for insomnia using a validated scale, a rate similar to those assessed with other scales in other countries. The study also showed that insomnia in alcohol-dependent patients is associated with poor physical health and childhood abuse, similar to the general population. The multifactorial nature of insomnia in alcohol-dependent patients has treatment implications.

Adenosine and glutamate signaling in neuron-glial interactions: implications in alcoholism and sleep disorders

Recent studies have demonstrated that the function of glia is not restricted to the support of neuronal function. Especially, astrocytes are essential for neuronal activity in the brain. Astrocytes actively participate in synapse formation and brain information processing by releasing or uptaking gliotransmitters such as glutamate, d-serine, adenosine 5'-triphosphate (ATP), and adenosine. In the central nervous system, adenosine plays an important role in regulating neuronal activity as well as in controlling other neurotransmitter systems such as GABA, glutamate, and dopamine. Ethanol (EtOH) increases extracellular adenosine levels, which regulates the ataxic and hypnotic/sedative (somnogenic) effects of EtOH. Adenosine signaling is also involved in the homeostasis of major inhibitory/excitatory neurotransmission (i.e., GABA or glutamate) through neuron-glial interactions, which regulates the effect of EtOH and sleep. Adenosine transporters or astrocytic SNARE-mediated transmitter release regulates extracellular or synaptic adenosine levels. Adenosine then exerts its function through several adenosine receptors and regulates glutamate levels in the brain. This review presents novel findings on how neuron-glial interactions, particularly adenosinergic signaling and glutamate uptake activity involving glutamate transporter 1 (GLT1), are implicated in alcoholism and sleep disorders.

Cause-specific mortality among a cohort of U.S. flight attendants

BACKGROUND

We evaluated mortality among 11,311 former U.S. flight attendants. The primary a priori outcomes of interest were breast cancer and melanoma.

METHODS

Vital status was ascertained through 2007, and life table analyses was conducted. Cumulative exposure to cosmic radiation and circadian rhythm disruption were estimated from work history data and historical published flight schedules.

RESULTS

All-cause mortality was less than expected among women but was elevated among men, primarily due to elevated HIV-related disease mortality. Mortality from breast cancer among women and melanoma was neither significantly elevated nor related to metrics of exposure. Mortality was elevated for non-Hodgkin's lymphoma among men; for alcoholism, drowning, and intentional self-harm among women; and for railway, water, and air transportation accidents.

CONCLUSIONS

We found no evidence of increased breast cancer or melanoma mortality. Limitations include reliance on mortality data and limited power resulting from few melanoma deaths and relatively short employment durations.

Cognitive and affective control in insomnia

Insomnia is a prevalent disabling chronic disorder. The aim of this paper is fourfold: (a) to review evidence suggesting that dysfunctional forms of cognitive control, such as thought suppression, worry, rumination, and imagery control, are associated with sleep disturbance; (b) to review a new budding field of scientific investigation - the role of dysfunctional affect control in sleep disturbance, such as problems with down-regulating negative and positive affective states; (c) to review evidence that sleep disturbance can impair next-day affect control; and (d) to outline, on the basis of the reviewed evidence, how the repetitive-thought literature and the affective science literature can be combined to further understanding of, and intervention for, insomnia.

Buprenorphine disrupts sleep and decreases adenosine concentrations in sleep-regulating brain regions of Sprague Dawley rat

BACKGROUND

Buprenorphine, a partial μ-opioid receptor agonist and κ-opioid receptor antagonist, is an effective analgesic. The effects of buprenorphine on sleep have not been well characterized. This study tested the hypothesis that an antinociceptive dose of buprenorphine decreases sleep and decreases adenosine concentrations in regions of the basal forebrain and pontine brainstem that regulate sleep.

METHODS

Male Sprague Dawley rats were implanted with intravenous catheters and electrodes for recording states of wakefulness and sleep. Buprenorphine (1 mg/kg) was administered systemically via an indwelling catheter and sleep-wake states were recorded for 24 h. In additional rats, buprenorphine was delivered by microdialysis to the pontine reticular formation and substantia innominata of the basal forebrain while adenosine was simultaneously measured.

RESULTS

An antinociceptive dose of buprenorphine caused a significant increase in wakefulness (25.2%) and a decrease in nonrapid eye movement sleep (-22.1%) and rapid eye movement sleep (-3.1%). Buprenorphine also increased electroencephalographic delta power during nonrapid eye movement sleep. Coadministration of the sedative-hypnotic eszopiclone diminished the buprenorphine-induced decrease in sleep. Dialysis delivery of buprenorphine significantly decreased adenosine concentrations in the pontine reticular formation (-14.6%) and substantia innominata (-36.7%). Intravenous administration of buprenorphine significantly decreased (-20%) adenosine in the substantia innominata.

CONCLUSIONS

Buprenorphine significantly increased time spent awake, decreased nonrapid eye movement sleep, and increased latency to sleep onset. These disruptions in sleep architecture were mitigated by coadministration of the nonbenzodiazepine sedative-hypnotic eszopiclone. The buprenorphine-induced decrease in adenosine concentrations in basal forebrain and pontine reticular formation is consistent with the interpretation that decreasing adenosine in sleep-regulating brain regions is one mechanism by which opioids disrupt sleep.

Sleep disturbance and the effects of extended-release zolpidem during cannabis withdrawal

BACKGROUND

Sleep difficulty is a common symptom of cannabis withdrawal, but little research has objectively measured sleep or explored the effects of hypnotic medication on sleep during cannabis withdrawal.

METHODS

Twenty daily cannabis users completed a within-subject crossover study. Participants alternated between periods of ad libitum cannabis use and short-term cannabis abstinence (3 days). Placebo was administered at bedtime during one abstinence period (withdrawal test) and extended-release zolpidem, a non-benzodiazepine GABA(A) receptor agonist, was administered during the other. Polysomnographic (PSG) sleep architecture measures, subjective ratings, and cognitive performance effects were assessed each day.

RESULTS

During the placebo-abstinence period, participants had decreased sleep efficiency, total sleep time, percent time spent in Stage 1 and Stage 2 sleep, REM latency and subjective sleep quality, as well as increased sleep latency and time spent in REM sleep compared with when they were using cannabis. Zolpidem attenuated the effects of abstinence on sleep architecture and normalized sleep efficiency scores, but had no effect on sleep latency. Zolpidem was not associated with any significant side effects or next-day cognitive performance impairments.

CONCLUSIONS

These data extend prior research that indicates abrupt abstinence from cannabis can lead to clinically significant sleep disruption in daily users. The findings also indicate that sleep disruption associated with cannabis withdrawal can be attenuated by zolpidem, suggesting that hypnotic medications might be useful adjunct pharmacotherapies in the treatment of cannabis use disorders.

Effect of night smoking, sleep disturbance, and their co-occurrence on smoking outcomes

Recent evidence suggests that smoking during the night is an indicator of nicotine dependence and predicts smoking cessation failure. Night smokers are likely to experience disturbance to their sleep cycle when they wake to smoke, but we are not aware of the prevalence of night smokers' self-reported sleep disturbance. Because sleep disturbance also predicts smoking cessation failure, we examined how the pre-cessation risk factors of night smoking and sleep disturbance, and their co-occurrence, predict smoking cessation failure in a 6-week double-blind randomized controlled trial examining whether naltrexone augments the efficacy of the nicotine patch (O'Malley et al., 2006). Smokers (N = 385) completed the Pittsburgh Sleep Quality Index (Buysse, Reynolds, Monk, Berman, & Kupfer, 1989) and a single item of waking at night to smoke pre-cessation. Smoking status was determined at weeks 1, 6, 24, and 48 weeks after quitting. The two main findings were: (a) night smokers reported significantly greater sleep disturbance than nonnight smokers; and (b) smokers with co-occurring night smoking and sleep disturbance experienced significantly greater risk for smoking than smokers with neither risk factor. Results suggest that individuals who both wake during the night to smoke and report clinically-significant sleep disturbance represent a high-risk group of smokers. Future smoking cessation treatment might incorporate strategies related to managing these smokers' sleep habits and physiological dependence on nicotine in order to bolster their cessation outcomes.

Sleep following alcohol intoxication in healthy, young adults: effects of sex and family history of alcoholism

BACKGROUND

This study evaluated sex and family history of alcoholism as moderators of subjective ratings of sleepiness/sleep quality and polysomnography (PSG) following alcohol intoxication in healthy, young adults.

METHODS

Ninety-three healthy adults [mean age 24.4 ± 2.7 years, 59 women, 29 subjects with a positive family history of alcoholism (FH+)] were recruited. After screening PSG, participants consumed alcohol (sex/weight adjusted dosing) to intoxication [peak breath alcohol concentration (BrAC) of 0.11 ± 0.01 g% for men and women] or matching placebo between 20:30 and 22:00 hours. Sleep was monitored using PSG between 23:00 and 07:00 hours. Participants completed the Stanford Sleepiness Scale and Karolinska Sleepiness Scale at bedtime and on awakening and a validated post-sleep questionnaire.

RESULTS

Following alcohol, total sleep time, sleep efficiency, nighttime awakenings, and wake after sleep onset were more disrupted in women than men, with no differences by family history status. Alcohol reduced sleep onset latency, sleep efficiency, and rapid eye movement sleep while increasing wakefulness and slow wave sleep across the entire night compared with placebo. Alcohol also generally increased sleep consolidation in the first half of the night, but decreased it during the second half. Sleepiness ratings were higher following alcohol, particularly in women at bedtime. Morning sleep quality ratings were lower following alcohol than placebo.

CONCLUSIONS

Alcohol intoxication increases subjective sleepiness and disrupts sleep objectively more in healthy women than in men, with no differences evident by family history of alcoholism status. Evaluating moderators of alcohol effects on sleep may provide insight into the role of sleep in problem drinking.

Sleeping problems among Chinese heroin-dependent individuals

BACKGROUND

Heroin abuse is a major public health problem with high morbidity and mortality. Treatment-seeking heroin-dependent subjects frequently report sleep-related problems that contribute to high relapse rates. Few studies have systematically studied the prevalence of sleep disorders among Chinese heroin-dependent subjects.

OBJECTIVES

This study aimed to explore the prevalence of sleep disorders with a battery of self-reported questionnaires in 140 heroin-dependent subjects in China.

METHODS

A self-report survey design was used to gather the data, using the Pittsburgh Sleep Quality Index (PSQI), Zung's Self-Rating Anxiety Scale (SAS), and Zung's Self-Rating Depression Scale (SDS). A total of 140 drug users participated in the survey.

RESULTS

PSQI results revealed that poor sleep quality (PSQI ≥ 8) was noted in 130 (96.30%) subjects. Those who displayed depressive symptoms, smoked and drank excessively, and had long-term histories of drug use had poorer sleep quality than those who did not. No correlation was found between anxiety, quantity of drugs, and sleeping disorders.

CONCLUSIONS

This study found that the majority of heroin-dependent patients reported poor sleep quality. Depression, smoking, drinking, and long-term drug use were associated with poor sleep quality in heroin-dependent individuals.

SCIENTIFIC SIGNIFICANCE

Despite the fact that this study collected data only using self-report measures, focused only on heroin-dependent patients, and did not include long-term follow-up study, given the potential link between poor sleep quality and relapse, factoring in this link is an important consideration as part of a comprehensive heroin-dependent treatment program.

Role of adenosine and wake-promoting basal forebrain in insomnia and associated sleep disruptions caused by ethanol dependence

Insomnia is a severe symptom of alcohol withdrawal; however, the underlying neuronal mechanism is yet unknown. We hypothesized that chronic ethanol exposure will impair basal forebrain (BF) adenosinergic mechanism resulting in insomnia-like symptoms. We performed a series of experiments in Sprague-Dawley rats to test our hypothesis. We used Majchrowicz's chronic binge ethanol protocol to induce ethanol dependency. Our first experiment verified the effects of ethanol withdrawal on sleep-wakefulness. Significant increase in wakefulness was observed during ethanol withdrawal. Next, we examined c-Fos expression (marker of neuronal activation) in BF wake-promoting neurons during ethanol withdrawal. There was a significant increase in the number of BF wake-promoting neurons with c-Fos immunoreactivity. Our third experiment examined the effects of ethanol withdrawal on sleep deprivation induced increase in BF adenosine levels. Sleep deprivation did not increase BF adenosine levels in ethanol dependent rats. Our last experiment examined the effects of ethanol withdrawal on equilibrative nucleoside transporter 1 and A1 receptor expression in the BF. There was a significant reduction in A1 receptor and equilibrative nucleoside transporter 1 expression in the BF of ethanol dependent rats. Based on these results, we suggest that insomnia observed during ethanol withdrawal is caused because of impaired adenosinergic mechanism in the BF.