Insomnia pharmacotherapy

Can we improve pain and sleep in elderly individuals with transcranial direct current stimulation? - Results from a randomized controlled pilot study

Background

The prevalence of chronic pain and sleep disturbances substantially increases with age. Pharmacotherapy remains the primary treatment option for these health issues. However, side effects and drug interactions are difficult to control in elderly individuals.

Aims

The objective of this study was to assess the feasibility of conducting a randomized sham-controlled trial and to collect preliminary data on the efficacy of transcranial direct current stimulation (tDCS) to reduce pain and improve sleep in older adults suffering from chronic pain.

Methods

Fourteen elderly individuals (mean age 71±7 years) suffering from chronic pain and sleep complaints were randomized to receive either anodal tDCS, applied over the primary motor cortex (2 mA, 20 minutes), or sham tDCS, for 5 consecutive days. Pain was measured with visual analog scales, pain logbooks and questionnaires, while sleep was assessed with actigraphy, sleep diaries and questionnaires.

Results

There were no missing data for pain and sleep measures, except for actigraphy, that generated several missing data. Blinding was maintained throughout the study, for both the evaluator and participants. Active but not sham tDCS significantly reduced pain (P<0.05). No change was observed in sleep parameters, in both the active and sham tDCS groups (all P≥0.18).

Conclusion

The present study provides guidelines for the implementation of future tDCS studies in larger populations of elderly individuals. M1 anodal tDCS in this population appears to be effective to reduce pain, but not to improve sleep.

Clinical profile of suvorexant for the treatment of insomnia over 3 months in women and men: subgroup analysis of pooled phase-3 data

RATIONALE

Sex-related differences in the clinical profiles of some insomnia medications have been previously reported.

OBJECTIVE

To evaluate the clinical profile of suvorexant, a novel orexin receptor antagonist approved for treating insomnia at doses up to 20 mg, by sex subgroups.

METHODS

Efficacy analyses by sex were based on pooled data from two similar phase 3, randomized, double-blind, placebo-controlled, 3-month trials in elderly (≥65 years) and non-elderly (18-64 years) insomnia patients. Two age-adjusted (non-elderly/elderly) dose regimes of 40/30 and 20/15 mg were evaluated, with fewer patients assigned to 20/15 mg. Efficacy was assessed by patient-reported outcomes (N = 1264 women, 707 men) and by polysomnography endpoints in ~75% of patients. Safety analyses by sex (N = 1744 women, 1065 men) included pooled data from the two 3-month trials plus 3-month data from a safety trial of 40/30 mg.

RESULTS

The sex subgroup efficacy analyses mirrored the improvements seen for suvorexant 40/30 and 20/15 mg over placebo on patient-reported outcomes and polysomnography sleep maintenance and onset endpoints in the primary analyses; 95% CIs excluded zero in favor of suvorexant for most endpoints in both sexes, and similar efficacy was observed between sexes (95% CIs overlapped). Suvorexant was well-tolerated in women and men, although women in all treatment groups (including placebo) reported more adverse events than men. The most frequent adverse event was somnolence (women: 11.1% for 40/30 mg, 8.5% for 20/15 mg, 2.3% for placebo; men: 10.1% for 40/30 mg, 3.4% for 20/15 mg, 4.2% for placebo).

CONCLUSION

Suvorexant was generally effective and well-tolerated in both women and men with insomnia. ClinicalTrials.gov trial registration numbers: NCT01097616, NCT01097629, NCT01021813.

The dual orexin receptor antagonist, DORA-22, lowers histamine levels in the lateral hypothalamus and prefrontal cortex without lowering hippocampal acetylcholine

Chronic insomnia is defined as a persistent difficulty with sleep initiation maintenance or non-restorative sleep. The therapeutic standard of care for this condition is treatment with gamma-aminobutyric acid (GABA)_A receptor modulators, which promote sleep but are associated with a panoply of side effects, including cognitive and memory impairment. Dual orexin receptor antagonists (DORAs) have recently emerged as an alternative therapeutic approach that acts via a distinct and more selective wake-attenuating mechanism with the potential to be associated with milder side effects. Given their distinct mechanism of action, the current work tested the hypothesis that DORAs and GABA_A receptor modulators differentially regulate neurochemical pathways associated with differences in sleep architecture and cognitive performance induced by these pharmacological mechanisms. Our findings showed that DORA-22 suppresses the release of the wake neurotransmitter histamine in the lateral hypothalamus, prefrontal cortex, and hippocampus with no significant alterations in acetylcholine levels. In contrast, eszopiclone, commonly used as a GABA_A modulator, inhibited acetylcholine secretion across brain regions with variable effects on histamine release depending on the extent of wakefulness induction. In normal waking rats, eszopiclone only transiently suppressed histamine secretion, whereas this suppression was more obvious under caffeine-induced wakefulness. Compared with the GABA_A modulator eszopiclone, DORA-22 elicits a neurotransmitter profile consistent with wake reduction that does not impinge on neurotransmitter levels associated with cognition and rapid eye movement sleep.

Tratamento da Insônia em Atenção Primária à Saúde

A insônia é uma das perturbações do sono mais comuns, sendo uma das principais queixas dos pacientes que recorrem aos cuidados médicos. A perturbação de insônia está associada a aumento da morbimortalidade por doenças cardiovasculares, psiquiátricas e acidentes, estando igualmente associada a maior absentismo laboral e maiores custos em saúde. Foram pesquisadas normas de orientação clínica, revisões sistemáticas, meta-análises e estudos originais, publicados entre 2010 e 15 de maio de 2015, relacionados com o tratamento da insônia. O tratamento da insônia pode iniciar-se por terapia cognitivo-comportamental, tratamento farmacológico ou associação dos dois. A terapia cognitivo-comportamental é considerada por várias sociedades médicas como tratamento padrão, sendo que os estudos comprovam a sua eficácia no tratamento da insônia sem ou com comorbilidades e com manutenção a longo prazo dos seus efeitos. Esta compreende múltiplas estratégias, como controle de estímulo, restrição do sono, relaxamento, terapia cognitiva e intenção paradoxal. A farmacoterapia deve ser considerada em situações agudas com necessidade de redução imediata dos sintomas. Os fármacos hipnóticos têm indicação no tratamento da insônia quando os sintomas assumem caráter patológico. Os antidepressivos sedativos, apesar de comumente utilizados, não reúnem evidência da sua eficácia, com exceção da insônia associada a sintomas depressivos ou de ansiedade ou em pacientes com abuso de substâncias. Assim, dada a prevalência de queixas de insônia em atenção primária à saúde, o médico de família deve conhecer a melhor abordagem para o seu tratamento, quer seja farmacológico ou não farmacológico, e os critérios de referenciação. 

Pharmaco-EEG Studies in Animals: A History-Based Introduction to Contemporary Translational Applications

Current research on the effects of pharmacological agents on human neurophysiology finds its roots in animal research, which is also reflected in contemporary animal pharmaco-electroencephalography (p-EEG) applications. The contributions, present value and translational appreciation of animal p-EEG-based applications are strongly interlinked with progress in recording and neuroscience analysis methodology. After the pioneering years in the late 19th and early 20th century, animal p-EEG research flourished in the pharmaceutical industry in the early 1980s. However, around the turn of the millennium the emergence of structurally and functionally revealing imaging techniques and the increasing application of molecular biology caused a temporary reduction in the use of EEG as a window into the brain for the prediction of drug efficacy. Today, animal p-EEG is applied again for its biomarker potential - extensive databases of p-EEG and polysomnography studies in rats and mice hold EEG signatures of a broad collection of psychoactive reference and test compounds. A multitude of functional EEG measures has been investigated, ranging from simple spectral power and sleep-wake parameters to advanced neuronal connectivity and plasticity parameters. Compared to clinical p-EEG studies, where the level of vigilance can be well controlled, changes in sleep-waking behaviour are generally a prominent confounding variable in animal p-EEG studies and need to be dealt with. Contributions of rodent pharmaco-sleep EEG research are outlined to illustrate the value and limitations of such preclinical p-EEG data for pharmacodynamic and chronopharmacological drug profiling. Contemporary applications of p-EEG and pharmaco-sleep EEG recordings in animals provide a common and relatively inexpensive window into the functional brain early in the preclinical and clinical development of psychoactive drugs in comparison to other brain imaging techniques. They provide information on the impact of drugs on arousal and sleep architecture, assessing their neuropharmacological characteristics in vivo, including central exposure and information on kinetics. In view of the clear disadvantages as well as advantages of animal p-EEG as compared to clinical p-EEG, general statements about the usefulness of EEG as a biomarker to demonstrate the translatability of p-EEG effects should be made with caution, however, because they depend on the particular EEG or sleep parameter that is being studied. The contribution of animal p-EEG studies to the translational characterisation of centrally active drugs can be furthered by adherence to guidelines for methodological standardisation, which are presently under construction by the International Pharmaco-EEG Society (IPEG).

Pharmacodynamic effects of suvorexant and zolpidem on EEG during sleep in healthy subjects

The objective of this study was to evaluate sleep electrophysiology in healthy subjects after bedtime administration of therapeutic doses of two insomnia treatments - the orexin receptor antagonist suvorexant or the GABAergic agonist zolpidem. Eighteen healthy men received single bedtime doses of suvorexant 20mg, zolpidem 10mg, or placebo in a double-blinded, randomized, balanced 3-period crossover study. EEG power spectral densities during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep were recorded in a polysomnography (PSG) laboratory using a 19-lead EEG recording array. Spectral density was analyzed for each lead for frequencies between 1-32Hz. During NREM and REM sleep, zolpidem treatment reduced spectral density across theta and alpha frequency bands in all leads. In contrast, suvorexant had no significant effects on spectral density in any frequency band during NREM sleep, and modestly increased spectral density in the theta frequency band during REM sleep. Although the study was not designed to detect effects on PSG sleep endpoints in healthy subjects, both suvorexant and zolpidem increased mean total sleep time and sleep efficiency. Zolpidem reduced latency to persistent sleep whereas suvorexant did not. Suvorexant decreased wake after sleep onset, whereas zolpidem did not. These findings suggest that EEG power spectral density profile after administration of suvorexant in healthy subjects more closely approximates placebo sleep physiology than after zolpidem treatment.

Suvorexant in Patients with Insomnia: Pooled Analyses of Three-Month Data from Phase-3 Randomized Controlled Clinical Trials

STUDY OBJECTIVES

Suvorexant is an orexin receptor antagonist approved for treating insomnia at a maximum dose of 20 mg. Phase-3 trials evaluated two age-adjusted (non-elderly/elderly) dose-regimes of 40/30 mg and 20/15 mg with the primary focus on 40/30 mg. We report here results from pooled analyses of the 20/15 mg dose-regime, which was evaluated as a secondary objective in the trials.

METHODS

Prespecified analysis of pooled data from two identical randomized, double-blind, placebo-controlled, parallel-group, 3-month trials in non-elderly (18-64 years) and elderly (≥ 65 years) patients with insomnia. Patients were randomized to suvorexant 20/15 mg (non-elderly/elderly), suvorexant 40/30 mg (non-elderly/elderly), or placebo; by design, fewer patients were randomized to 20/15 mg. Efficacy was assessed by self-reported and polysomnography (PSG; subset of patients) sleep maintenance and onset endpoints.

RESULTS

Suvorexant 20/15 mg (N = 493 treated) was effective compared to placebo (N = 767 treated) on patient-reported and PSG sleep maintenance and onset endpoints at Night-1 (PSG endpoints) / Week-1 (subjective endpoints), Month-1 and Month-3, except for effects on PSG sleep onset at Month-3. Suvorexant 20/15 mg was generally well tolerated, with 3% of patients discontinuing due to adverse events over 3 months vs. 5.2% on placebo. Somnolence was the most common adverse event (6.7% vs. 3.3% for placebo). There was no systematic evidence of rebound or withdrawal signs or symptoms when suvorexant was discontinued after 3 months of nightly use.

CONCLUSIONS

Suvorexant 20/15 mg improved sleep onset and maintenance over 3 months of nightly treatment and was generally safe and well tolerated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov trial registration numbers: NCT01097616, NCT01097629.

Postoperative use of hypnotics is associated with increased length of stay after uncomplicated surgery for colorectal cancer

Background/Aims:

Hypnotics are used to treat perioperative sleep disorders. These drugs are associated with a higher risk of adverse effects among patients undergoing surgery. This study aims to quantify the use of hypnotics and factors influencing the administration of hypnotics in relation to colorectal cancer surgery.

Method:

A retrospective cohort study of 1979 patients undergoing colorectal cancer surgery.

Results:

In all, 381 patients (19%) received new treatment with hypnotics. Two of the six surgical centres used hypnotics less often (odds ratio (95% confidence interval), 0.24 (0.16–0.38) and 0.20 (0.12–0.35)). Active smokers (odds ratio (95% confidence interval), 1.57 (1.11–2.24)) and patients receiving perioperative blood transfusion (odds ratio (95% confidence interval), 1.58 (1.10–2.26)) had increased likelihood of receiving hypnotics. In the uncomplicated cases, a multivariable linear regression analysis showed that consumption of hypnotics postoperatively was significantly associated with increased length of stay (1.5 (0.9–2.2) days).

Conclusion:

One in five patients began treatment with hypnotics after colorectal cancer surgery. Postoperative use of hypnotics was associated with an increased length of stay for uncomplicated cases of colorectal cancer surgery.

Assessing and Managing Sleep Disturbance in Patients with Chronic Pain

Chronic pain is associated with symptoms that may impair a patient's quality of life, including emotional distress, fatigue, and sleep disturbance. There is a high prevalence of concomitant pain and sleep disturbance. Studies support the hypothesis that sleep and pain have a bidirectional and reciprocal relationship. Clinicians who manage patients with chronic pain often focus on interventions that relieve pain, and assessing and treating sleep disturbance are secondary or not addressed. This article reviews the literature on pain and co-occurring sleep disturbance, describes the assessment of sleep disturbance, and outlines nonpharmacologic and pharmacologic treatment strategies to improve sleep in patients with chronic pain.

Towards quantitative cutoffs for insomnia: how current diagnostic criteria mischaracterize remission

OBJECTIVE

Although sleep symptoms of insomnia can be quantified, none of the current diagnostic systems stipulate quantitative cutoffs for sleep-onset latency (SOL) or wake time after sleep onset (WASO). Diagnoses are based instead on idiographic patient reports of "difficulty" falling/staying asleep. Therefore, we examined whether remission of insomnia as per the diagnostic criteria results from a normalization of quantitative sleep disturbance, or if it is simply reflective of tolerance to sleep symptoms.

METHODS

This study involved a yearlong prospective investigation of 649 adults (48.1 ± 11.6 years; 69.3% female) with DSM-5-based insomnia. Participants completed measures of sleep disturbance, perceived sleep-related distress, daytime sleepiness, functional impairment, and workplace productivity at baseline and follow-up one year later.

RESULTS

A total of 271 participants no longer met the DSM-5-based insomnia criteria at follow-up. However, 66% of these remitters reported ≥31 min of SOL and/or WASO. Daytime impairment in this subgroup of remitters was no different from that among individuals who met the diagnostic criteria at both baseline and follow-up (ie, chronic insomniacs). By contrast, follow-up impairment was significantly lower (F = 12.3; P < 0.01) among remitters whose sleep disturbance returned below empirically derived quantitative cutoffs (both SOL and WASO <31 min) than in chronic insomniacs.

CONCLUSION

This is the first study on the long-term course of insomnia based on the newly established DSM-5 criteria. A troubling implication of findings is that a majority of insomniacs stop meeting the diagnostic criteria despite continued sleep disturbance and impairment. "Remission" in these cases is attributable instead to tolerance of sleep symptoms. Incorporating quantitative criteria into current diagnoses may offer a more sensitive assay of treatment needs.

Suvorexant in Patients With Insomnia: Results From Two 3-Month Randomized Controlled Clinical Trials

BACKGROUND

Suvorexant is an orexin receptor antagonist for treatment of insomnia. We report results from two pivotal phase 3 trials.

METHODS

Two randomized, double-blind, placebo-controlled, parallel-group, 3-month trials in nonelderly (18-64 years) and elderly (≥65 years) patients with insomnia. Suvorexant doses of 40/30 mg (nonelderly/elderly) and 20/15 mg (nonelderly/elderly) were evaluated. The primary focus was 40/30 mg, with fewer patients randomized to 20/15 mg. There was an optional 3-month double-blind extension in trial 1. Each trial included a 1-week, randomized, double-blind run-out after double-blind treatment to assess withdrawal/rebound. Efficacy was assessed at week 1, month 1, and month 3 by patient-reported subjective total sleep time and time to sleep onset and in a subset of patients at night 1, month 1, and month 3 by polysomnography end points of wakefulness after persistent sleep onset and latency to onset of persistent sleep (LPS). One thousand twenty-one patients were randomized in trial 1 and 1019 patients in trial 2.

RESULTS

Suvorexant 40/30 mg was superior to placebo on all subjective and polysomnography end points at night 1/week 1, month 1, and month 3 in both trials, except for LPS at month 3 in trial 2. Suvorexant 20/15 mg was superior to placebo on subjective total sleep time and wakefulness after persistent sleep onset at night 1/week 1, month 1, and month 3 in both trials and at most individual time points for subjective time to sleep onset and LPS in each trial. Both doses of suvorexant were generally well tolerated, with <5% of patients discontinuing due to adverse events over 3 months. The results did not suggest the emergence of marked rebound or withdrawal signs or symptoms when suvorexant was discontinued.

CONCLUSIONS

Suvorexant improved sleep onset and maintenance over 3 months of nightly treatment and was generally safe and well tolerated.

Profile of suvorexant in the management of insomnia

Suvorexant, approved in late 2014 in the United States and Japan for the treatment of insomnia characterized by difficulty achieving and/or maintaining sleep, is a dual orexin receptor antagonist and the first drug in its class to reach the market. Its development followed from the 1998 discovery of orexins (also called hypocretins), excitatory neuropeptides originating from neurons in the hypothalamus involved in regulation of sleep and wake, feeding behavior and energy regulation, motor activity, and reward-seeking behavior. Suvorexant objectively improves sleep, shortening the time to achieve persistent sleep and reducing wake after sleep onset, although at approved doses (≤20 mg) the benefit was subjectively assessed as modest. Its half-life of 12 hours is relatively long for a modern hypnotic; however, at approved doses (≤20 mg) next-day sedation and driving impairment were much less apparent than at higher doses. Suvorexant is metabolized by the hepatic CYP3A system and should be avoided in combination with strong CYP3A inhibitors. Drug levels are higher in women and obese people; hence, dosing should be conservative in obese women. Administration with food delays drug absorption and is not advised. No dose adjustment is needed for advanced age, renal impairment, or mild-to-moderate hepatic impairment. Suvorexant in contraindicated in narcolepsy and has not been studied in children. In alignment with the changes begun in 2013 in the labeling of other hypnotics, the United States Food and Drug Administration advises that the lowest dose effective to treat symptoms be used and that patients be advised of the possibility of next-day impairment in function, including driving. Infrequent but notable side effects included abnormal dreams, sleep paralysis, and suicidal ideation that were dose-related and reported to be mild. Given its mechanism of action, cataplexy and rapid eye movement (REM) sleep behavior disorder could potentially occur in some patients taking this medication.

Comparison of Body, Auricular, and Abdominal Acupuncture Treatments for Insomnia Differentiated as Internal Harassment of Phlegm-Heat Syndrome: An Orthogonal Design

Objective. To identify the optimum treatment protocol for insomnia among auricular, body, and abdominal needling methods. Methods. A three-factor (3 needling protocols) and three-level experimental scheme was designed based on orthogonal method. 54 patients of insomnia differentiated as internal harassment of phlegm-heat syndrome were given two courses of acupuncture treatment (each with 20 times of acupuncture). The therapeutic effects were evaluated by comparing the Pittsburgh sleep quality index (PSQI), Hamilton Depression Scale (HAMD) scores, and Hamilton Anxiety Scale (HAMA) scores of patients before treatment, after one course of treatment, and after two courses of treatment as well as one month after treatment. Results. Body, auricular, and abdominal acupuncture treatments all alleviated symptoms of insomnia, depression, and anxiety, but body and auricular acupuncture had stronger therapeutic effects. Conclusions. Body acupuncture at basic points shall be given priority in protocol selection for insomnia. The second-best choice is auricular acupuncture with basic points combined with points based on Traditional Chinese Medicine (TCM) theories. Abdominal needling with very quick effect can be an alternative protocol with basic points combined with syndrome differentiation points.

Effects of suvorexant on sleep architecture and power spectral profile in patients with insomnia: analysis of pooled phase 3 data

BACKGROUND

The orexin receptor antagonist, suvorexant, is approved for treating insomnia at a maximum dose of 20 mg. We evaluated its effects on sleep architecture.

METHODS

The analyses included pooled polysomnography data from two similar randomized, double-blind, placebo-controlled, 3-month trials evaluating two age-adjusted (non-elderly/elderly) dose regimes of 20/15 mg and 40/30 mg in 1482 patients with insomnia. Polysomnography was recorded at baseline and on three nights during the treatment: Night-1, Month-1, and Month-3. Effects on non-REM sleep stages 1 (N1), 2 (N2), 3 (N3)/slow wave sleep (SWS), and REM sleep were evaluated. A power spectral analysis of non-REM sleep was also performed.

RESULTS

Suvorexant increased the time (in minutes) spent in all sleep stages compared with placebo. When suvorexant and placebo were compared in terms of changes in percentage of total sleep time spent in each stage, there were small decreases of ≤1%, ≤2.2%, and ≤0.8% for N1, N2, and N3/SWS on average, respectively, and an average increase of ≤3.9% in REM. The largest differences from placebo were observed at Night-1 and generally diminished over time. Suvorexant reduced REM latency (number of non-REM 30-s epochs from lights-off to the first REM epoch) compared with placebo; the reduction was greater at Night-1 (~40-50 non-REM epochs) in comparison to later time points (~12-25 non-REM epochs at Month-3). The spectral analysis of non-REM showed a small decrease in power of 3-6% in the gamma and beta bands, and a small increase of 4-8% in the delta band, at Night-1 for suvorexant relative to placebo; these effects were not apparent at the later Month-1 and Month-3 time points.

CONCLUSION

Overall sleep architecture appears to be preserved in insomnia patients taking suvorexant. The power spectral profile of suvorexant is generally similar to placebo.

Small-molecule antagonists of the orexin receptors

The orexin-1 and orexin-2 receptors are two G protein-coupled receptors that bind the neuropeptides orexin-A and orexin-B. Dual antagonism of the receptors by small molecules is clinically efficacious in the treatment of insomnia, where the most advanced molecule suvorexant has recently been approved. The scope of this article is to review the small molecule orexin receptor antagonist patent literature between January 2012 and January 2014.

Assessment and treatment of insomnia in adult patients with alcohol use disorders

Insomnia in patients with alcohol dependence has increasingly become a target of treatment due to its prevalence, persistence, and associations with relapse and suicidal thoughts, as well as randomized controlled studies demonstrating efficacy with behavior therapies and non-addictive medications. This article focuses on assessing and treating insomnia that persists despite 4 or more weeks of sobriety in alcohol-dependent adults. Selecting among the various options for treatment follows a comprehensive assessment of insomnia and its multifactorial causes. In addition to chronic, heavy alcohol consumption and its effects on sleep regulatory systems, contributing factors include premorbid insomnia; co-occurring medical, psychiatric, and other sleep disorders; use of other substances and medications; stress; environmental factors; and inadequate sleep hygiene. The assessment makes use of history, rating scales, and sleep diaries as well as physical, mental status, and laboratory examinations to rule out these factors. Polysomnography is indicated when another sleep disorder is suspected, such as sleep apnea or periodic limb movement disorder, or when insomnia is resistant to treatment. Sobriety remains a necessary, first-line treatment for insomnia, and most patients will have some improvement. If insomnia-specific treatment is needed, then brief behavioral therapies are the treatment of choice, because they have shown long-lasting benefit without worsening of drinking outcomes. Medications work faster, but they generally work only as long as they are taken. Melatonin agonists; sedating antidepressants, anticonvulsants, and antipsychotics; and benzodiazepine receptor agonists each have their benefits and risks, which must be weighed and monitored to optimize outcomes. Some relapse prevention medications may also have sleep-promoting activity. Although it is assumed that treatment for insomnia will help prevent relapse, this has not been firmly established. Therefore, insomnia and alcohol dependence might be best thought of as co-occurring disorders, each of which requires its own treatment.

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.

Menopause and sleep

CLINICAL SCENARIO

An obese, 50-year-old woman complains of hot flashes, poor sleep, snoring, and daytime sleepiness. She states that these problems have bothered her for about 4 years. Her partner recently complained about her snoring and restlessness, prompting this visit. She has become hypertensive. What should she do?

Discovery of HTL6641, a dual orexin receptor antagonist with differentiated pharmacodynamic properties

A novel series of potent, selective, and orally efficacious dual antagonists of the orexin receptors is described.

Cognitive-behavioral therapy for chronic insomnia

OPINION STATEMENT

Psychological and behavioral therapies should be considered the first line treatment for chronic insomnia. Although cognitive behavioral therapy for insomnia (CBT-I) is considered the standard of care [1], several monotherapies, including sleep restriction therapy, stimulus control therapy, and relaxation training are also recommended in the treatment of chronic insomnia [2]. CBT-I is a multimodal intervention comprised of a combination of behavioral (eg, sleep restriction, stimulus control) and cognitive therapy strategies, and psychoeducation delivered in 4 to 10 weekly or biweekly sessions [3]. Given that insomnia is thought to be maintained by an interaction between unhelpful sleep-related beliefs and behaviors, the goal of CBT-I is to modify the maladaptive cognitions (eg, worry about the consequences of poor sleep), behaviors (eg, extended time in bed), and arousal (ie, physiological and mental hyperarousal) perpetuating the insomnia. CBT-I is efficacious when implemented alone or in combination with a pharmacologic agent. However, because of the potential for relapse upon discontinuation, CBT-I should be extended throughout drug tapering [4]. Although the treatment options should be guided by the available evidence supporting both psychological therapies and short-term hypnotic treatment, as well as treatment feasibility and availability, treatment selection should ultimately be guided by patient preference [5]. Despite its widespread use among treatment providers [6], the use of sleep hygiene education as a primary intervention for insomnia should be avoided. Sleep hygiene may be a necessary, but insufficient condition for promoting good sleep and should be considered an adjunct to another empirically supported treatment.

Electroencephalographic power spectral density profile of the orexin receptor antagonist suvorexant in patients with primary insomnia and healthy subjects

STUDY OBJECTIVES

Suvorexant, an orexin receptor antagonist, improves sleep in healthy subjects (HS) and patients with insomnia. We compared the electroencephalographic (EEG) power spectral density (PSD) profile of suvorexant with placebo using data from a phase 2 trial in patients with insomnia. We also compared suvorexant's PSD profile with the profiles of other insomnia treatments using data from 3 HS studies.

DESIGN

Phase 2 trial--randomized, double-blind, two-period (4 w per period) crossover. HS studies--randomized, double-blind, crossover.

SETTING

Sleep laboratories.

PARTICIPANTS

Insomnia patients (n = 229) or HS (n = 124).

INTERVENTIONS

Phase 2 trial--suvorexant 10 mg, 20 mg, 40 mg, 80 mg, placebo; HS study 1--suvorexant 10 mg, 50 mg, placebo; HS study 2--gaboxadol 15 mg, zolpidem 10 mg, placebo; HS study 3--trazodone 150 mg, placebo.

MEASUREMENTS AND RESULTS

The PSD of the EEG signal at 1-32 Hz of each PSG recording during nonrapid eye movement (NREM) and rapid eye movement (REM) sleep were calculated. The day 1 and day 28 PSD profiles of suvorexant at all four doses during NREM and REM sleep in patients with insomnia were generally flat and close to 1.0 (placebo) at all frequencies. The day 1 PSD profile of suvorexant in HS was similar to that in insomnia patients. In contrast, the other three drugs had distinct PSD profiles in HS that differed from each other.

CONCLUSIONS

Suvorexant at clinically effective doses had limited effects on power spectral density compared with placebo in healthy subjects and in patients with insomnia, in contrast to the three comparison insomnia treatments. These findings suggest the possibility that antagonism of the orexin pathway might lead to improvements in sleep without major changes in the patient's neurophysiology as assessed by electroencephalographic.

Differential sleep-promoting effects of dual orexin receptor antagonists and GABAA receptor modulators

BACKGROUND

The current standard of care for insomnia includes gamma-aminobutyric acid receptor A (GABAA) activators, which promote sleep as well as general central nervous system depression. Dual orexin receptor antagonists (DORAs) represent an alternative mechanism for insomnia treatment that induces somnolence by blocking the wake-promoting effects of orexin neuropeptides. The current study compares the role and interdependence of these two mechanisms on their ability to influence sleep architecture and quantitative electroencephalography (qEEG) spectral profiles across preclinical species.

RESULTS

Active-phase dosing of DORA-22 induced consistent effects on sleep architecture in mice, rats, dogs, and rhesus monkeys; attenuation of active wake was accompanied by increases in both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. Eszopiclone, a representative GABAA receptor modulator, promoted sleep in rats and rhesus monkeys that was marked by REM sleep suppression, but had inconsistent effects in mice and paradoxically promoted wakefulness in dogs. Active-phase treatment of rats with DORA-12 similarly promoted NREM and REM sleep to magnitudes nearly identical to those seen during normal resting-phase sleep following vehicle treatment, whereas eszopiclone suppressed REM even to levels below those seen during the active phase. The qEEG changes induced by DORA-12 in rats also resembled normal resting-phase patterns, whereas eszopiclone induced changes distinct from normal active- or inactive-phase spectra. Co-dosing experiments, as well as studies in transgenic rats lacking orexin neurons, indicated partial overlap in the mechanism of sleep promotion by orexin and GABA modulation with the exception of the REM suppression exclusive to GABAA receptor modulation. Following REM deprivation in mice, eszopiclone further suppressed REM sleep while DORA-22 facilitated recovery including increased REM sleep.

CONCLUSION

DORAs promote NREM and importantly REM sleep that is similar in proportion and magnitude to that seen during the normal resting phase across mammalian animal models. While limited overlap exists between therapeutic mechanisms, orexin signaling does not appear involved in the REM suppression exhibited by GABAA receptor modulators. The ability of DORAs to promote proportional NREM and REM sleep following sleep deprivation suggests that this mechanism may be effective in alleviating recovery from sleep disturbance.

Discovery and development of orexin receptor antagonists as therapeutics for insomnia

Insomnia persistently affects the quality and quantity of sleep. Currently approved treatments for insomnia primarily target γ-aminobutyric acid-A (GABA-A) receptor signalling and include benzodiazepines and GABA-A receptor modulators. These drugs are used to address this sleep disorder, but have the potential for side effects such as tolerance and dependence, making them less attractive as maintenance therapy. Forward and reverse genetic approaches in animals have implicated orexin signalling (also referred to as hypocretin signalling) in the control of vigilance and sleep/wake states. Screening for orexin receptor antagonists using in vitro and in vivo methods in animals has identified compounds that block one or other of the orexin receptors (single or dual orexin receptor antagonists [SORAs and DORAs], respectively) in animals and humans. SORAs have primarily been used as probes to further elucidate the roles of the individual orexin receptors, while a number of DORAs have progressed to clinical development as pharmaceutical candidates for insomnia. The DORA almorexant demonstrated significant improvements in a number of clinically relevant sleep parameters in animal models and in patients with insomnia but its development was halted. SB-649868 and suvorexant have demonstrated efficacy and tolerability in Phase II and III trials respectively. Furthermore, suvorexant is currently under review by the Food and Drug Administration for the treatment of insomnia. Based on the publication of recent non-clinical and clinical data, orexin receptor antagonists potentially represent a targeted, effective and well-tolerated new class of medications for insomnia.

Recommendations of the Sleep Study Group of the Italian Dementia Research Association (SINDem) on clinical assessment and management of sleep disorders in individuals with mild cognitive impairment and dementia: a clinical review

Clinical assessment and management of sleep disturbances in patients with mild cognitive impairment and dementia has important clinical and social implications. Poor sleep results in an increased risk of morbidities and mortality in demented patients and is a source of stress for caregivers. Sleep disturbances show high prevalence in mild cognitive impairment and dementia patients and they are often associated one to another in the same patient. A careful clinical evaluation of sleep disorders should be performed routinely in the clinical setting of individuals with cognitive decline. The Sleep Study Group of the Italian Dementia Research Association (SINDem) reviewed evidence from original research articles, meta-analyses and systematic reviews published up to December 2013. The evidence was classified in quality levels (I, II, III) and strength of recommendations (A, B, C, D, E). Where there was a lack of evidence, but clear consensus, good practice points were provided. These recommendations may not be appropriate for all circumstances and should therefore be adopted only after a patient's individual characteristics have been carefully evaluated.

Rapid tolerance development to the NREM sleep promoting effect of alcohol

STUDY OBJECTIVES

Alcohol tolerance is a major contributor towards the development of alcohol dependence. Does alcohol intake result in rapid tolerance development to alcohol induced NREM sleep promotion? This has never been examined. Our objective was to examine whether two bouts of alcohol consumption on consecutive days results in rapid tolerance development to alcohol-induced NREM sleep promotion.

DESIGN

N/A.

SETTING

N/A.

PATIENTS OR PARTICIPANTS

C57BL/6J mice.

INTERVENTIONS

Mice (N = 5) were implanted with sleep electrodes using standard surgical conditions. Following postoperative recovery and habituation, the experiment was begun. On baseline day, water bottle changes were performed at 10:00 (3 h after dark onset) and 14:00 to mimic conditions during alcohol consumption days. On next 2 days, (Days 1 and 2) mice were allowed to self-administer alcohol (20% v/v) for 4 h beginning at 10:00 and ending at 14:00. Sleep-wakefulness was continuously recorded from 10:00 to 18:00 (8 h; 4 h during alcohol + 4 h post-alcohol) on all 3 days.

MEASUREMENTS AND RESULTS

Although mice consumed comparable amounts of alcohol on Days 1 and 2, NREM sleep and wakefulness were significantly and differentially affected during 4 h post-alcohol period. A robust alcohol-induced NREM sleep promotion was observed on Day 1. However, no such sleep promotion was observed on Day 2, suggesting rapid tolerance development.

CONCLUSIONS

Our study is the first to demonstrate that alcohol consumption for two consecutive days results in development of rapid tolerance to alcohol-induced sleep promotion.

Safety and efficacy of suvorexant during 1-year treatment of insomnia with subsequent abrupt treatment discontinuation: a phase 3 randomised, double-blind, placebo-controlled trial

BACKGROUND

Suvorexant (MK-4305) is an orexin receptor antagonist shown to be efficacious for insomnia over 3 months. We aimed to assess its clinical profile during and after 1 year of treatment.

METHODS

We did a randomised, placebo-controlled, parallel-group trial at 106 investigational centres in the Americas, Australia, Europe, and South Africa from December, 2009, to August, 2011. Patients aged 18 years or older with primary insomnia by DSM-IV-TR criteria were assigned using a computer-generated randomised allocation schedule to receive nightly suvorexant (40 mg for patients younger than 65 years, 30 mg for patients aged 65 years or older) or placebo at a 2:1 ratio for 1 year with a subsequent 2-month randomised discontinuation phase in which patients on suvorexant either continued suvorexant or were abruptly switched to placebo while patients on placebo remained on placebo. Treatment assignment was masked from patients and investigators. The primary objective was to assess the safety and tolerability of suvorexant for up to 1 year. Secondary objectives were to assess the efficacy of suvorexant for improving patient-reported subjective total sleep time (sTST) and time to sleep onset (sTSO) over the first month of treatment. Efficacy endpoints over the first month were assessed with a mixed model with terms for baseline value of the response variable, age, sex, region, treatment, time, and treatment by time interaction. This trial is registered with ClinicalTrials.gov, number NCT01021813.

FINDINGS

322 (62%) of 522 patients randomly assigned to receive suvorexant and 162 (63%) of 259 assigned to receive placebo completed the 1-year phase. Over 1 year, 362 (69%) of 521 patients treated with suvorexant experienced any adverse events compared with 164 (64%) of 258 treated with placebo. Serious adverse events were recorded in 27 patients (5%) who received suvorexant and 17 (7%) who received placebo. The most common adverse event, somnolence, was reported for 69 patients (13%) who received suvorexant and seven (3%) who received placebo. At month 1, suvorexant (517 patients in the efficacy population) showed greater efficacy than placebo (254 in the efficacy population) in improving sTST (38·7 min vs 16·0 min; difference 22·7, 95% CI 16·4 to 29·0; p<0·0001) and sTSO (-18·0 min vs -8·4 min, difference -9·5, -14·6 to -4·5; p=0·0002).

INTERPRETATION

Our findings show that suvorexant was generally safe and well tolerated over 1 year of nightly treatment in patients with insomnia, with efficacy noted for subjective measures of sleep onset and maintenance.

FUNDING

Merck & Co Inc.

The duration of sleep promoting efficacy by dual orexin receptor antagonists is dependent upon receptor occupancy threshold

Background

Drugs targeting insomnia ideally promote sleep throughout the night, maintain normal sleep architecture, and are devoid of residual effects associated with morning sedation. These features of an ideal compound are not only dependent upon pharmacokinetics, receptor binding kinetics, potency and pharmacodynamic activity, but also upon a compound’s mechanism of action.

Results

Dual orexin receptor antagonists (DORAs) block the arousal-promoting activity of orexin peptides and, as demonstrated in the current work, exhibit an efficacy signal window dependent upon oscillating levels of endogenous orexin neuropeptide. Sleep efficacy of structurally diverse DORAs in rat and dog was achieved at plasma exposures corresponding to orexin 2 receptor (OX₂R) occupancies in the range of 65 to 80%. In rats, the time course of OX₂R occupancy was dependent upon receptor binding kinetics and was tightly correlated with the timing of active wake reduction. In rhesus monkeys, direct comparison of DORA-22 with GABA-A modulators at similar sleep-inducing doses revealed that diazepam produced next-day residual sleep and both diazepam and eszopiclone induced next-day cognitive deficits. In stark contrast, DORA-22 did not produce residual effects. Furthermore, DORA-22 evoked only minimal changes in quantitative electroencephalogram (qEEG) activity during the normal resting phase in contrast to GABA-A modulators which induced substantial qEEG changes.

Conclusion

The higher levels of receptor occupancy necessary for DORA efficacy require a plasma concentration profile sufficient to maintain sleep for the duration of the resting period. DORAs, with a half-life exceeding 8 h in humans, are expected to fulfill this requirement as exposures drop to sub-threshold receptor occupancy levels prior to the wake period, potentially avoiding next-day residual effects at therapeutic doses.

Optimizing sleep in older adults: treating insomnia

As the world's population ages, the elevated prevalence of insomnia in older adults is a growing concern. Insomnia is characterized by difficulty falling or remaining asleep, or by non-restorative sleep, and resultant daytime dysfunction. In addition to being at elevated risk for primary insomnia, older adults are at greater risk for comorbid insomnia, which results from, or occurs in conjunction with another medical or psychiatric condition. In this review, we discuss normal changes in sleep that accompany aging, circadian rhythm changes and other factors that can contribute to late-life insomnia, useful tools for the assessment of insomnia and related problems in older people, and both non-pharmacological and pharmacological strategies for the management of insomnia and optimization of sleep in later life.