The sleep-wake cycle and sleeping pills

Prevention and control of jet lag symptoms and temporary impairment of cognitive function with Pycnogenol® in healthy individuals and in hypertensives

BACKGROUND

The aim of this registry study was to evaluate the efficacy of Pycnogenol® in controlling signs/symptoms and temporary impairment of cognitive function (COFU) associated with jet lag. Previous flight studies have shown a decrease in the level of jet lag symptoms with Pycnogenol®. The control of jet lag signs/symptoms appeared to be correlated with flight-related microangiopathy and peripheral edema. Pycnogenol® - a standardized extract from the bark of French maritime pine - has significant antiedema, anti-inflammatory and antioxidant properties.

METHODS

A group of subjects flying east in economy class for 10-12 hours used Pycnogenol® 150 mg/day and a similar group without supplementation served as controls. A subgroup of mild hypertensive subjects using a single ACE inhibitor was also included.

RESULTS

One hundred twenty-seven subjects completed the study. Of the participants, 48 were aviation professionals like pilots, flight attendants or air company staff - 24 of them took Pycnogenol® and 24 served as controls. Forty-seven study participants were frequent flyers and non-staff professionals, 25 of which took Pycnogenol® and 22 served as controls. In addition, a group of 32 subjects with mild hypertension was included, 16 took Pycnogenol® and 16 served as controls. No side effects and a good tolerability were observed. The registry groups were comparable for baseline characteristics. Eastbound flights' duration was 11.22±0.4 hours in supplemented subjects and 11.14±0.32 in controls. Dropouts were due to logistical problems. Post flight Visual Analogue Scale (VAS) scores were significantly lower in all Pycnogenol® groups, including hypertensives for all signs and symptoms of jet lag compared to controls, showing prevention and improvement of jet lag symptoms. The duration of any sign/symptom of jet lag with Pycnogenol® intake was significantly shorter (P<0.05) post-flight compared to controls (P<0.05). The number of nights of altered/disturbed sleep was also lower in the Pycnogenol® groups compared to controls. Leg edema was present in almost all subjects with different degrees especially in the hypertensive group. The increase in ankle circumference before and after flight was significantly lower with Pycnogenol® compared to controls (P<0.05). After the flight, average scores of the single COFU tasks were significantly higher in the Pycnogenol® groups compared to controls, showing preserved cognitive function.

CONCLUSIONS

In conclusion, in this registry study Pycnogenol® was effective in preventing jet lag-related symptoms and preserving cognitive functions without tolerability problems. These observations should be tested in a larger group of subjects including complex individuals prone to edema (i.e. diabetics, hypertensive or older patients).

Single use of psychoactive substances and its association with sleep disorders and sleep health in a large US college sample

OBJECTIVE

Estimate the association between single (i.e., exclusive) use of a range of substances and sleep outcomes.

PARTICIPANTS

College students participated in the 2015-2019 American College-Health Association-National College-Health Assessment survey.

METHODS

Multivariable logistic and linear regressions were used.

RESULTS

Single users of sedative, opioid, tobacco, and stimulant drugs were more likely to report a diagnosis of insomnia and other sleep disorder and indicated more days per week of negative sleep health outcomes compared not only to non-users of these substances but also polysubstance users. Single users of alcohol were significantly less likely to report a diagnosis of sleep disorder and indicated having had more days per week of positive sleep health outcomes compared to non-alcohol users and polysubstance users. However, those results are reversed for binge drinking.

CONCLUSIONS

Support of programs addressing behaviors to reduce the high prevalence of psychoactive substance use and sleep disturbances in college youth is needed.

Treating insomnia in people who are incarcerated: a feasibility study of a multicomponent treatment pathway

Around 60% of people who are incarcerated have insomnia; 6-10 times more prevalent than the general population. Yet, there is no standardized, evidence-based approach to insomnia treatment in prison. We assessed the feasibility of a treatment pathway for insomnia in a high-secure prison to inform a future randomized controlled trial (RCT) and initial efficacy data for sleep and mental health outcomes. We used a within-participants pre-post design. The stepped-care pathway included: self-management with peer support, environmental aids, and cognitive behavioral therapy for insomnia (CBTi). Assessment measures for insomnia, well-being, mood, anxiety, suicidality, overall health, sleepiness, fatigue, and cognitive functioning were administered at baseline and pathway exit. Feasibility criteria included eligibility to participate, CBTi uptake, and assessment completion. Forty-two adult males who are incarcerated were approached of which 95.2% were eligible. Of those deemed eligible, most participated (36/40, 90.0%). Most who completed baseline completed post-assessments (28/36, 77.8%) and of these, most showed improvements in their subjective sleep (27/28, 96.4%). Large reductions were found from pre- to posttreatment in insomnia severity (d = -1.81, 95% CI: 8.3 to 12.9) and 57.0% reported no clinically significant insomnia symptoms at post-assessment. There was no overall change in actigraphy-measured sleep. Large treatment benefits were found for depression, anxiety, well-being, and cognitive functioning, with a medium benefit on suicidal ideation. The treatment pathway for insomnia in prison was feasible and may be an effective treatment for insomnia in people who are incarcerated, with additional promising benefits for mental health. A pragmatic RCT across different prison populations is warranted. This paper is part of the Sleep and Circadian Health in the Justice System Collection.

Iodine/TBHP-Mediated One-Pot Multicomponent Protocol for Tandem C-N and C-S Bond Formation To Access Sulfenylimidazo[1,5-a]pyridines via C-H Functionalization

A mild and simple protocol has been established for the formation of sulfenylated imidazo[1,5-a]pyridines. This is a metal-free iodine/TBHP-mediated one-pot multicomponent reaction, which follows C-H functionalization of the imidazo[1,5-a]pyridine skeleton formed during the reaction and its subsequent sulfenylation in the same step to offer sulfenylated imidazo[1,5-a]pyridines in good to high yields. The extension and applications of this method have also been demonstrated.

Pu-erh tea increases the metabolite Cinnabarinic acid to improve circadian rhythm disorder-induced obesity

Obesity is one of the circadian rhythm disorders (CRD)-mediated metabolic disorder syndromes. Pu-erh tea is a viable dietary intervention for CRD, however its effect on CRD-induced obesity is unclear. Here, we found that Pu-erh tea improved obesity in CRD-induced mice, which stemmed from the production of Cinnabarinic acid (CA). CA promoted adipose tissue lipolysis and thermogenic response (HSL, ATGL, Pparα, CKB, UCP1) and increased adipocyte sensitivity to hormones and neurotransmitters by targeting the expression of adipose tissue receptor proteins (Q6KAT8, P51655, A2AKQ0, M0QWX7, Q6ZQ33, and mGluR4). This improved mitochondrial activity and facilitated adipose tissue metabolic processes, thereby accelerating glucolipid metabolism. Also, CA-induced alterations in gut microbes and short-chain fatty acids further improved CRD-mediated lipid accumulation. These results suggest that the increase of CA caused by Pu-erh tea, targeted to adipose tissue via the metabolite-blood circulation-adipose tissue axis, maybe a key mechanism for reducing the development of CRD-induced obesity.

AI Empowered Virtual Reality Integrated Systems for Sleep Stage Classification and Quality Enhancement

Insomnia is a common public health problem and an open biomedical research topic. Insomnia results in various health problems, including memory decline, decreases concentration and weakens problem-solving ability. The insufficient sleep also leads to skin ageing, heart disease, high blood pressure, arrhythmia and stroke. While it remains as a global health concern, sleep quality improvement using modern technologies, such as machine learning, classification technologies, virtual reality (VR), becomes an open and hot research problem. These modern technologies offer new curing solutions under certain conditions. In this paper, we present a sleeping-aid system with a single-channel electroencephalogram (EEG) sleep stage classification algorithm to improve the sleep quality. The sleeping-aid system promotes machine learning integrated VR and multimedia technology for sleep improvement. Ninety participants were invited to test on three different systems with 3D VR, 2D video, and music only. An adequate stimulus of audio-vision can be a complement of the drug treatment. The experimental results showed that the proposed method demonstrated superior performance over existing methods.

Pu-erh Tea Restored Circadian Rhythm Disruption by Regulating Tryptophan Metabolism

Pu-erh tea is a healthy beverage rich in phytochemicals, and its effect on the risk of inducing circadian rhythm disorders (CRD) is unclear. In this study, healthy mice were given water or 0.25% (w/v) Pu-erh tea for 7 weeks, followed by a 40 day disruption of the light/dark cycle. CRD caused dysregulation of neurotransmitter secretion and clock gene oscillations, intestinal inflammation, and disruption of intestinal microbes and metabolites. Pu-erh tea boosted the indole and 5-hydroxytryptamine pathways of tryptophan metabolism via the gut-liver-brain axis. Furthermore, its metabolites (e.g., IAA, Indole, 5-HT) enhanced hepatic glycolipid metabolism and down-regulated intestinal oxidative stress by improving the brain hormone release. Tryptophan metabolites and bile acids also promoted liver lipid metabolism and inhibited intestinal inflammation (MyD88/NF-κB) via the enterohepatic circulation. Collectively, 0.25% (w/v) Pu-erh tea has the potential to prevent CRD by promoting indole and 5-HT pathways of tryptophan metabolism and signaling interactions in the gut-liver-brain axis.

Tea combats circadian rhythm disorder syndrome via the gut-liver-brain axis: potential mechanisms speculated

Circadian rhythm is an intrinsic mechanism developed by organisms to adapt to external environmental signals. Nowadays, owing to the job and after-work entertainment, staying up late - Circadian rhythm disorders (CRD) are common. CRD is linked to the development of fatty liver, type 2 diabetes, and chronic gastroenteritis, which affecting the body's metabolic and inflammatory responses via multi-organ crosstalk (gut-liver-brain axis, etc.). However, studies on the mechanisms of multi-organ interactions by CRD are still weak. Current studies on therapeutic agents for CRD remain inadequate, and phytochemicals have been shown to alleviate CRD-induced syndromes that may be used for CRD-therapy in the future. Tea, a popular phytochemical-rich beverage, reduces glucolipid metabolism and inflammation. But it is immature and unclear in the mechanisms of alleviation of CRD-mediated syndrome. Here, we have analyzed the threat of CRD to hosts and their offspring' health from the perspective of the "gut-liver-brain" axis. The potential mechanisms of tea in alleviating CRD were further explored. It might be by interfering with bile acid metabolism, tryptophan metabolism, and G protein-coupled receptors, with FXR, AHR, and GPCR as potential targets. We hope to provide new perspectives on the role of tea in the prevention and mitigation of CRD.HighlightsThe review highlights the health challenges of CRD via the gut-liver-brain axis.CRD research should focus on the health effects on healthy models and its offspring.Tea may prevent CRD by regulating bile acid, tryptophan, and GPCR.Potential targets for tea prevention and mitigation of CRD include FXR, AHR and GPCR.A comprehensive assessment mechanism for tea in improving CRD should be established.

The effect of zolpidem on targeted memory reactivation during sleep

According to the active system consolidation theory, memory consolidation during sleep relies on the reactivation of newly encoded memory representations. This reactivation is orchestrated by the interplay of sleep slow oscillations, spindles, and theta, which are in turn modulated by certain neurotransmitters like GABA to enable long-lasting plastic changes in the memory store. Here we asked whether the GABAergic system and associated changes in sleep oscillations are functionally related to memory reactivation during sleep. We administered the GABAA agonist zolpidem (10 mg) in a double-blind placebo-controlled study. To specifically focus on the effects on memory reactivation during sleep, we experimentally induced such reactivations by targeted memory reactivation (TMR) with learning-associated reminder cues presented during post-learning slow-wave sleep (SWS). Zolpidem significantly enhanced memory performance with TMR during sleep compared with placebo. Zolpidem also increased the coupling of fast spindles and theta to slow oscillations, although overall the power of slow spindles and theta was reduced compared with placebo. In an uncorrected exploratory analysis, memory performance was associated with slow spindle responses to TMR in the zolpidem condition, whereas it was associated with fast spindle responses in placebo. These findings provide tentative first evidence that GABAergic activity may be functionally implicated in memory reactivation processes during sleep, possibly via its effects on slow oscillations, spindles and theta as well as their interplay.

Zolpidem improves patients' sleep quality after surgical treatment for infective endocarditis: a prospective observational study

PURPOSE

The objective of this study was to investigate the efficacy of zolpidem for improving post-operative sleep quality among patients with infective endocarditis (IE) and to identify the potential risk factors for impaired sleep quality at 6 months after surgery.

METHODS

Patients with IE who underwent surgical treatment were divided into two groups according to zolpidem usage. The Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) were used to evaluate patients' sleep quality and daytime sleepiness at baseline, which was the second day after transferal, and at 6 months after surgery. Logistic regression was used to identify potential risk factors.

RESULTS

There were 32 patients in the zolpidem group and 42 in the control group. The PSQI and ESS scores at 6 months after surgery were significantly lower than those at baseline in both groups (P = 0.04). Additionally, 9 patients (28%) in the zolpidem group and 22 patients (52%) in the control group suffered poor sleep quality. Multivariate analysis identified age (odds ratio [OR] = 1.26, 95% confidence interval [CI]: 1.12-1.42), baseline PSQI score (OR = 2.66, 95%CI: 1.55-4.65), and no zolpidem usage (OR = 45.48, 95%CI: 3.01-691.23) as independent factors for poor sleep quality.

CONCLUSIONS

Poor sleep quality after IE surgery was prevalent among patients even 6 months after IE surgery. Age, baseline PSQI score and no zolpidem usage were independently associated with poor sleep quality. Therefore, zolpidem has the potential to be an effective part of a treatment arsenal for poor sleep quality after surgical treatment for IE.

Prevalence and factors associated with use of sleeping pills among older adults in Brazil

OBJECTIVES

Little is known about sleeping pills consumption among older adults in low- and middle-income countries. This study investigated the prevalence and factors associated with sleeping pills use among Brazilians aged 50 and over.

METHODS

A cross-sectional study was conducted using baseline data from the Brazilian Longitudinal Study of Aging (ELSI-Brazil), a nationally representative study of persons aged 50 years and older (n = 9412). Univariate and bivariate analyses were used to describe the sample. Robust Poisson regression was employed to estimate prevalence ratios and predict probabilities.

KEY FINDINGS

Prevalence of sleeping pills use among older Brazilians was estimated at 16.8%, with considerable disparities related to gender (22.3% among women and 10.3% among men), race/skin colour (19.7% among whites and 11.9% among blacks) and geographic region (ranging from 5.9% in the North to 20.5% in the South). The multivariate analysis showed associations between sleeping pills consumption and sociodemographic factors (age, gender, race/skin colour, geographic region and income), health status/behaviour characteristics (poor self-rated health status, number of chronic conditions and alcohol consumption) and variables related to healthcare utilisation (number of visits, usual source of care, care coordination, doctor's awareness of all medication, difficulty in managing own medication and number of medicines).

CONCLUSIONS

Our work found that sleeping pills consumption is disproportionately prevalent among women, is associated with worse health status and increases with more medical office visits and use of additional medicines. Moreover, the large inexplicable variations in care deserve special attention from policy-makers and clinicians.

Prescribed drugs containing nitrogen heterocycles: an overview

Heteroatoms as well as heterocyclic scaffolds are frequently present as the common cores in a plethora of active pharmaceuticals natural products. Statistically, more than 85% of all biologically active compounds are heterocycles or comprise a heterocycle and most frequently, nitrogen heterocycles as a backbone in their complex structures. These facts disclose and emphasize the vital role of heterocycles in modern drug design and drug discovery. In this review, we try to present a comprehensive overview of top prescribed drugs containing nitrogen heterocycles, describing their pharmacological properties, medical applications and their selected synthetic pathways. It is worth mentioning that the reported examples are actually limited to current top selling drugs, being or containing N-heterocycles and their synthetic information has been extracted from both scientific journals and the wider patent literature.

Synthesis and Structure-Activity Relationships of Imidazopyridine/Pyrimidine- and Furopyridine-Based Anti-infective Agents against Trypanosomiases

Neglected tropical diseases remain among the most critical public health concerns in Africa and South America. The drug treatments for these diseases are limited, which invariably leads to fatal cases. Hence, there is an urgent need for new antitrypanosomal drugs. To address this issue, a large number of diverse heterocyclic compounds were prepared. Straightforward synthetic approaches tolerated pre-functionalized structures, giving rise to a structurally diverse set of analogs. We report on a set of 57 heterocyclic compounds with selective activity potential against kinetoplastid parasites. In general, 29 and 19 compounds of the total set could be defined as active against Trypanosoma cruzi and T. brucei brucei, respectively (antitrypanosomal activities <10 μM). The present work discusses the structure-activity relationships of new fused-ring scaffolds based on imidazopyridine/pyrimidine and furopyridine cores. This library of compounds shows significant potential for anti-trypanosomiases drug discovery.

Sleep, circadian rhythms and health

At the core of human thought, for the majority of individuals in the developed nations at least, there is the tacit assumption that as a species we are unfettered by the demands imposed by our biology and that we can do what we want, at whatever time we choose, whereas in reality every aspect of our physiology and behaviour is constrained by a 24 h beat arising from deep within our evolution. Our daily circadian rhythms and sleep/wake cycle allow us to function optimally in a dynamic world, adjusting our biology to the demands imposed by the day/night cycle. The themes developed in this review focus upon the growing realization that we ignore the circadian and sleep systems at our peril, and this paper considers the mechanisms that generate and regulate circadian and sleep systems; what happens mechanistically when these systems collapse as a result of societal pressures and disease; how sleep disruption and stress are linked; why sleep disruption and mental illness invariably occur together; and how individuals and employers can attempt to mitigate some of the problems associated with working against our internal temporal biology. While some of the health costs of sleep disruption can be reduced, in the short-term at least, there will always be significant negative consequences associated with shift work and sleep loss. With this in mind, society needs to address this issue and decide when the consequences of sleep disruption are justified in the workplace.

The Effects of Intraoperative Dexmedetomidine Use and Its Different Dose on Postoperative Sleep Disturbance in Patients Who Have Undergone Non-Cardiac Major Surgery: A Real-World Cohort Study

OBJECTIVE

The study aimed to investigate the effects of intraoperative dexmedetomidine on postoperative sleep disturbance for different surgical patients and compare such effects between different dose of dexmedetomidine.

METHODS

A total of 7418 patients undergoing nine types of non-cardiac major surgeries were retrospectively studied. Patients were separated into DEX (dexmedetomidine) or Non-DEX (Non-dexmedetomidine) groups based on the use of dexmedetomidine during surgery. The patients who reported they could not fall asleep during the night or woke up repeatedly during the most of the night at the day of the surgery and whose NRS were >6 were defined as cases with severe sleep disturbance. Propensity score matched analysis based on all preoperative baseline data was performed along with logistic regression analysis including different surgery types and dosage of dexmedetomidine use.

RESULTS

In both of the unmatched cohort (OR, 0.49 [95% CI: 0.43-0.56]) and matched cohort (0.49 [95% CI: 0.42-0.58]), the DEX group had a significantly lower incidence of severe sleep disturbance than the Non-DEX group. In the subgroup analysis, for gynecological and urological surgery population, the ORs for DEX-group reached 0.21 (95% CI, 0.13-0.33; P<0.0001) and 0.30 (95% CI,0.19-0.47; P<0.0001), respectively. In addition, low-dose dexmedetomidine (0.2-0.4 μg·kg^-1·h^-1) showed the greatest effect with an odds ratio of 0.38 (95% CI: 0.31-0.44; P<0.0001), and the incidence of severe sleep disturbance in the low-dose group was significantly lower (11.5% vs. 17.7% vs. 16.5%, P<0.0001) than that in the medium- (0.4-0.6 μg·kg^-1·h^-1) and high-dose (0.6-0.8 μg·kg^-1·h^-1) groups.

CONCLUSION

Intraoperative dexmedetomidine use can significantly decrease the incidence of severe sleep disturbance on the day of surgery for patients undergoing non-cardiac major surgery, and the effects were most significant in patients receiving gynecological and urological surgery. Furthermore, low-dose dexmedetomidine (0.2-0.4 μg·kg^-1·h^-1) is most effective for prevention of postoperative sleep disturbance.

Concurrent use of opioids with benzodiazepines or nonbenzodiazepine sedatives among patients with cancer referred to an outpatient palliative care clinic

BACKGROUND

The concurrent use of opioids with benzodiazepines (BZD) or nonbenzodiazepine sedatives (S) recently was found to be associated with an increased risk of overdose death compared with the use of opioids alone. In the current study, the authors examined the frequency and trend of concurrent opioid/BZD-S use and its associated risk factors among patients with cancer.

METHODS

Data regarding the frequency and trend of concurrent opioid/BZD-S use were extracted for 1500 randomly selected patients referred to the outpatient palliative care clinic at The University of Texas MD Anderson Cancer Center between the calendar years of 2011 and 2016. To explore associated risk factors, the authors compared the demographic and clinical predictors of 418 patients each in the concurrent opioid/BZD-S group and opioids-only group.

RESULTS

In 2011, at the time of referral to the palliative care clinic, 96 of 221 patients with cancer (43%) were prescribed concurrent opioids/BZD-S. This rate progressively declined to 67 of 217 patients (31%) by 2016 (P = .0008). Patients in the concurrent opioid/BZD-S group had a higher percentage of females (233 individuals; 55% [P = .007]) and whites (323 individuals; 77% [P = .002]), and patients reported higher scores regarding depression (P = .0001), anxiety (P ≤ .0001), drowsiness (P = .048), and worst feeling of well-being (P = .001). The morphine equivalent daily dose was significantly higher in concurrent opioid/BZD-S group (median of 67.5 mg/day [interquartile range (IQR), 30-135 mg/day] vs 60 mg/day [IQR, 30-105 mg/day]; P = .034). Multivariate analysis demonstrated that anxiety (P ≤ .0001), white race (P = .0092), and poor Eastern Cooperative Oncology Group performance status (P = .0017) were significantly associated with concurrent use.

CONCLUSIONS

The concurrent use of opioids with BZD-S has declined but continues to be frequent among patients with cancer. Anxiety, white race, and poor Eastern Cooperative Oncology Group performance status were associated with its use. More research is needed to explore which medications can replace these agents.

Improve postoperative sleep: what can we do?

Purpose of review

We reviewed evidences regarding occurrence, risk factors, harmful effects, prevention, and management of sleep disturbances in patients after surgery.

Recent findings

Normal sleep is important to maintain physical and mental health. Sleep disturbances frequently occur in patients after surgery. Factors associated with the development of postoperative sleep disturbances include old age, preoperative comorbidity, type of anesthesia, severity of surgical trauma, postoperative pain, environment stress, as well as other factors leading to discomfort of patients. Development of sleep disturbances produces harmful effects on postoperative patients, that is, leading to higher risk of delirium, increased sensitivity to pain, more cardiovascular events, and poorer recovery. Both nonpharmacological and pharmacological measures (such as zolpidem, melatonin, and dexmedetomidine) can be used to improve postoperative sleep. Recent evidences show that sleep promotion may improve patients’ outcome, but requires further evidences.

Summary

Sleep disturbances are common in patients after surgery and produce harmful effects on postoperative recovery. Sleep-promotion therapy may be helpful to improve postoperative recovery, but long-term effects deserve further study.

An improved and scalable synthesis of zolpidem via a CuI/BINOL-mediated tandem reaction of imine and alkyne

An improved and scalable method for the synthesis of zolpidem (

Pharmacological Targeting the REV-ERBs in Sleep/Wake Regulation

The circadian clock maintains appropriate timing for a wide range of behaviors and physiological processes. Circadian behaviors such as sleep and wakefulness are intrinsically dependent on the precise oscillation of the endogenous molecular machinery that regulates the circadian clock. The identical core clock machinery regulates myriad endocrine and metabolic functions providing a link between sleep and metabolic health. The REV-ERBs (REV-ERBα and REV-ERBβ) are nuclear receptors that are key regulators of the molecular clock and have been successfully targeted using small molecule ligands. Recent studies in mice suggest that REV-ERB-specific synthetic agonists modulate metabolic activity as well as alter sleep architecture, inducing wakefulness during the light period. Therefore, these small molecules represent unique tools to extensively study REV-ERB regulation of sleep and wakefulness. In these studies, our aim was to further investigate the therapeutic potential of targeting the REV-ERBs for regulation of sleep by characterizing efficacy, and optimal dosing time of the REV-ERB agonist SR9009 using electroencephalographic (EEG) recordings. Applying different experimental paradigms in mice, our studies establish that SR9009 does not lose efficacy when administered more than once a day, nor does tolerance develop when administered once a day over a three-day dosing regimen. Moreover, through use of a time response paradigm, we determined that although there is an optimal time for administration of SR9009 in terms of maximal efficacy, there is a 12-hour window in which SR9009 elicited a response. Our studies indicate that the REV-ERBs are potential therapeutic targets for treating sleep problems as those encountered as a consequence of shift work or jet lag.

Later sleep schedule and depressive symptoms are associated with usage of multiple kinds of hypnotics

OBJECTIVE

Usage of high doses of hypnotics possibly causes various adverse events. However, the risk factors of using multiple kinds of hypnotics have been inconclusive. To clarify this, we conducted a web-based cross-sectional questionnaire survey on the Japanese adult population.

METHODS

A cross-sectional Internet-linked survey was conducted on 10,016 individuals and 1030 participants (10.3%) having subjective insomnia proceeded to subsequent analyses. The analyzed subjects were categorized into non-users of hypnotics (n = 833; 80.9%), users of a single kind of hypnotic (n = 96; 9.3%), and users of multiple kinds of hypnotics (n = 101; 9.8%). The descriptive variables including demographic data, scores of Center for Epidemiological Studies Depression Scale (CES-D), Short Form-8 Health-Related Quality of Life [QOL (SF-8)], Pittsburgh Sleep Quality Index (PSQI), and other parameters were compared among the groups.

RESULTS

The users of multiple kinds of hypnotics had the highest mean score of CES-D, the lowest mental component summary of QOL (SF-8), and the latest sleep schedule among the three groups (p < 0.001). Logistic regression analyses revealed that sex (female: OR = 2.38; p < 0.001) and age (≥43 years old: OR = 2.61; p < 0.001) were independently associated with use of a single kind of hypnotic, while later sleep schedule (midpoint of sleep ≥5:30 a.m.: OR = 2.26; p < 0.001) and higher CES-D score (≥16 points: OR = 2.41; p < 0.001) were independently associated with use of multiple kinds of hypnotics.

CONCLUSIONS

Characteristics of users of multiple kinds of hypnotics were different from those of users of a single kind of hypnotic.

Impact of hypnotics use on daytime function and factors associated with usage by female shift work nurses

OBJECTIVE

We investigated quality of life (QOL) and work performance of hypnotics users, and explored the factors associated with multiple hypnotics usage in shift work nurses.

METHODS

We conducted a questionnaire-based, cross-sectional survey on nurses in university hospitals. We analyzed responses from 1202 nurses; 997 were female shift work nurses (82.9%), including 696 and 281 two- and three-shift workers, respectively.

RESULTS

The rate of hypnotics use was 10% (6.9% were single hypnotic users and 3.1% were multiple hypnotics users). The rate of insomnia did not differ between the single and multiple hypnotics users. However, multiple hypnotics users showed lower QOL, more severe depressive symptoms, and greater frequencies of work-related errors than those using a single hypnotic. A multiple logistic regression analysis revealed that age ≥27 years, presence of depression, eveningness chronotype, and presence of insomnia symptoms were significantly associated with hypnotics use. On the other hand, only the existence of shift work disorder (SWD) was significantly associated with usage of multiple hypnotics.

CONCLUSIONS

The present study suggested that usage of multiple hypnotics is not beneficial for relieving insomnia or for keeping better QOL in shift work nurses. It would be desirable to explore the causal relationship between SWD and multiple hypnotics use in a future longitudinal study.

Retrospective population cohort study on hip fracture risk associated with zolpidem medication

STUDY OBJECTIVE

Few studies have evaluated the hip fracture risk for zolpidem users. We assessed the risk for subjects taking zolpidem.

DESIGN

Population-based retrospective cohort study using claims data of a universal insurance system.

PARTICIPANTS

We identified 6,978 patients newly prescribed for zolpidem in 2000-2001 age 18 y and older, and 27,848 nonusers frequency matched with sex, age, and date visiting a clinic.

MEASUREMENTS AND RESULTS

Both cohorts were followed up to the end of 2008 to measure the hip fracture incidence and risk, which considered factors such as sex, age, occupation, days of drug use, and osteoporosis status. The zolpidem users had a 2.23-fold higher hip fracture incidence than nonusers (3.10 versus 1.39 per 1,000 person-y). The risk increased with age for both cohorts. The elderly users had a 21-fold higher incidence than the younger users, or twofold higher than the elderly nonusers. Among 33 patients (20.4%) with hip fracture occurring during presumed medication days, which was accountable for an incidence of 1,083.0 per 1,000 person-y. Those taking the medicine for 8 days or longer had a moderately higher fracture rate than those taking it for less days (6.02 versus 4.48 per 100 person-times) with a ratio of 1.34 (95% confidence interval 0.42-4.56). Subjects with blue collar occupations were at a higher fracture risk.

CONCLUSION

The hip fracture risk of zolpidem users is higher than that of nonusers. Fracture prevention awareness should be disseminated to the users.

A case of Zolpidem dependence successfully detoxified with gabapentin

An elderly female patient with Zolpidem dependence, who was successfully detoxified using Gabapentin is reported. Gabapentin may be considered as an alternative in the detoxification of non-benzodiazepine hypnotics.

Structure-based development of bacterial nitroreductase against nitrobenzodiazepine-induced hypnosis

Nitrobenzodiazepine (NBDZ) is an addictive drug of the abused substances that causes severe neurological effects and even death. Bacterial type I nitroreductase NfsB (EC 1.5.1.34) has been reported to catalyze NBDZ into inactive metabolite 7-amino-benzodiazepine (7ABDZ) with promising activity, so as to become an attractive candidate for treatment of NBDZ overdose and addiction. Here, we investigate the nitroreduction of an NBDZ, flunitrazepam (FZ), by various mutants of NfsB designed from the solved crystal structure and characterize their in vitro and in vivo potency. Conformational changes occurred in the active site of N71S/F124W in contrast to the wild-type, including the flipping on the aromatic rings of W124 and F70 as well as the extension on the hydrogen bond network between flavin mononucleotide (FMN) and S71, which allow the significant enlargement in the active site pocket. In the complex structure of N71S/F124W and nicotinamide (NIA), stacking sandwich attractions of W124-FMN-NIA were also found, implying the importance of W124 in substrate accessibility. Consequently, N71S/F124W exhibited increased 7AFZ production in vitro with nearly no toxicity and reduced 50% sleeping time (hypnosis) in vivo. Taken together, we demonstrate for the first time that N71S/F124W can serve as an effective antidote for NBDZ-induced hypnosis and provide the molecular basis for designing NfsB and the like in the future.

Diagnosis and treatment of chronic insomnia

Insomnia is a disorder characterized by inability to sleep or a total lack of sleep, prevalence of which ranges from 10 to 15% among the general population with increased rates seen among older ages, female gender, White population and presence of medical or psychiatric illness. Yet this condition is still under-recognized, under-diagnosed, and under-treated. This article aims to review the operational definitions and management of chronic insomnia. A computerized search on PubMed carried from 1980 to January 2009 led to the summarization of the results. There are several strategies to manage chronic insomnia. To initiate treatment, it is necessary to define it and differentiate it from other co-morbid psychiatric disorders. Non-pharmacologic strategies such as stimulus control therapy and relaxation and cognitive therapies have the best effect sizes followed by sleep restriction, paradoxical intention and sleep hygiene education which have modest to less than modest effect sizes. Among pharmacotherapeutic agents, non-benzodiazepine hypnotics are the first line of management followed by benzodiazepines, amitryptiline and antihistaminics. However, adequate trials of combined behavior therapy and pharmacotherapy are the best course of management.

Effects of ramelteon on insomnia symptoms induced by rapid, eastward travel

OBJECTIVE

Ramelteon, an MT(1)/MT(2) melatonin receptor agonist, was evaluated for its ability to reduce sleep-onset difficulties associated with eastward jet travel.

METHODS

Healthy adults (n=110) with a history of jet lag sleep disturbances were flown eastward across five time zones from Hawaii to the east coast of the US. Ramelteon 1, 4, or 8 mg or placebo was administered 5 min before bedtime (local time) for four nights. Sleep parameters were measured using polysomnography (PSG) on Nights 2, 3, and 4. Next-day residual effects were assessed using psychomotor and memory function tests.

RESULTS

Compared to placebo, there was a significant decrease in mean latency to persistent sleep (LPS) on Nights 2-4 with ramelteon 1mg (-10.64 min, P=0.030). No consistent significant differences were observed with ramelteon vs. placebo on measures of next-day residual effects except on Day 4 where participants in all ramelteon groups performed significantly worse on the immediate memory recall test compared with placebo (P < or = 0.05). The incidence of adverse events was similar for ramelteon and placebo.

CONCLUSION

After a 5-h phase advance due to eastward jet travel, ramelteon 1mg taken before bedtime for four nights reduced mean LPS relative to placebo in healthy adults.

Neuropharmacological screening of two 1,5-benzodiazepine compounds in mice

This work investigates whether the two 1,5-benzodiazepine compounds: 4-(2-hydroxyphenyl)-1,5-benzodiazepin-2-one (RG0501) and Benzopyrano [4,3-c] 1,5-benzodiazepine (RG0502) have any neuropharmacological activities. Diazepam and Flunitrazepam were used as drug references. The investigational 1,5-BDZ were tested in vivo for potentiating hexobarbital-induced sleep and pentylenetetrazole (PTZ)-induced seizures. Our study demonstrated that the increase of sleep duration was significantly higher with RG0501 as compared to RG0502. However, RG0502 anticonvulsant effect was more pronounced than that of RG0501 in the range dose of 6.25-37.5 mg.kg(-1). From the 50 mg.kg(-1) dose, RG0502 offered a protection against clonic-tonic seizures as well as lethality (p< or =0.05). The results showed that the required doses to obtain a pharmacological activity were more than those of the references. This difference could be related to the lack of specific substituants responsible for the pharmacological activity in the tested compounds.

Role of GABAA receptors in the physiology and pharmacology of sleep

Most sedative-hypnotics used in insomnia treatment target the gamma-aminobutyric acid (GABA)(A) receptors. A vast repertoire of GABA(A) receptor subtypes has been identified and displays specific electrophysiological and functional properties. GABA(A)-mediated inhibition traditionally refers to 'phasic' inhibition, arising from synaptic GABA(A) receptors which transiently inhibit neurons. However, there is growing evidence that peri- or extra-synaptic GABA(A) receptors are continuously activated by low GABA concentrations and mediate a 'tonic' conductance. This slower type of signaling appears to play a key role in controlling cell excitability. This review aims at summarizing recent knowledge on GABA transmission, including the emergence of tonic conductance, and highlighting the importance of GABA(A) receptor heterogeneity. The mechanism of action of sedative-hypnotic drugs and their effects on sleep and the electroencephalogram will be reported. Furthermore, studies using genetically engineered mice will be emphasized, providing insights into the role of GABA(A) receptors in mechanisms underlying physiological and pharmacological sleep. Finally, we will address the potential of GABA(A) receptor pharmacology for the treatment of insomnia.

Some chronobiological and physiological problems associated with long-distance journeys

Long-distance travel is becoming increasingly common. Whatever the means of transport, any long journey will be associated with "travel fatigue". The symptoms associated with this phenomenon result from a changed routine (particularly sleep lost and meals) and the general disruption caused by travel. Planning any trip well in advance will minimise many of these problems, but some factors are less easy to guard against. These problems include sitting in cramped and uncomfortable conditions and, with flights, the hypoxic environment in the cabin. After arrival at the destination in another country, there can be problems coping with the local language, alterations in food and different customs. If the flight has crossed the equator, then there is likely to be a change in season and natural lighting and, if it has crossed several time zones, there will also be the problem of "jet lag", caused by a transient desynchrony between the "body clock" and the new local time. Moreover, the new environment might differ from the place of departure with regard to ambient temperature and humidity, altitude, natural lighting (including ultraviolet radiation) and pollution. The traveller needs to be aware of these changes before setting off, so that appropriate preparations (clothing, for example) can be made.