Sedative-hypnotics and human performance

Diazepam effects on local cortical neural activity during sleep in mice

GABA-ergic neurotransmission plays a key role in sleep regulatory mechanisms and in brain oscillations during sleep. Benzodiazepines such as diazepam are known to induce sedation and promote sleep, however, EEG spectral power in slow frequencies is typically reduced after the administration of benzodiazepines or similar compounds. EEG slow waves arise from a synchronous alternation between periods of cortical network activity (ON) and silence (OFF), and represent a sensitive marker of preceding sleep-wake history. Yet it remains unclear how benzodiazepines act on cortical neural activity during sleep. To address this, we obtained chronic recordings of local field potentials and multiunit activity (MUA) from deep cortical layers of the primary motor cortex in freely behaving mice after diazepam injection. We found that the amplitude of individual LFP slow waves was significantly reduced after diazepam injection and was accompanied by a lower incidence and duration of the corresponding neuronal OFF periods. Further investigation suggested that this is due to a disruption in the synchronisation of cortical neurons. Our data suggest that the state of global sleep and local cortical synchrony can be dissociated, and that the brain state induced by benzodiazepines is qualitatively different from spontaneous physiological sleep.

Non-benzodiazepine hypnotic use for sleep disturbance in people aged over 55 years living with dementia: a series of cohort studies

BACKGROUND

Sleep disturbance affects around 60% of people living with dementia and can negatively affect their quality of life and that of their carers. Hypnotic Z-drugs (zolpidem, zopiclone and zaleplon) are commonly used to treat insomnia, but their safety and efficacy have not been evaluated for people living with dementia.

OBJECTIVES

To estimate the benefits and harms of Z-drugs in people living with dementia with sleep disturbance.

DESIGN

A series of observational cohort studies using existing data from (1) primary care linked to hospital admission data and (2) clinical cohort studies of people living with dementia.

DATA SOURCES

Primary care study - Clinical Practice Research Datalink linked to Hospital Episode Statistics and Office for National Statistics mortality data. Clinical cohort studies - the Resource Use and Disease Course in Dementia - Nursing Homes (REDIC) study, National Alzheimer's Coordinating Centre (NACC) clinical data set and the Improving Well-being and Health for People with Dementia (WHELD) in nursing homes randomised controlled trial.

SETTING

Primary care study - 371 primary care practices in England. Clinical cohort studies - 47 nursing homes in Norway, 34 Alzheimer's disease centres in the USA and 69 care homes in England.

PARTICIPANTS

Primary care study - NHS England primary care patients diagnosed with dementia and aged > 55 years, with sleep disturbance or prescribed Z-drugs or low-dose tricyclic antidepressants, followed over 2 years. Clinical cohort studies - people living with dementia consenting to participate, followed over 3 years, 12 years and 9 months, for REDIC, NACC and WHELD, respectively.

INTERVENTIONS

The primary exposure was prescription or use of Z-drugs. Secondary exposures included prescription or use of benzodiazepines, low-dose tricyclic antidepressants and antipsychotics.

MAIN OUTCOME MEASURES

Falls, fractures, infection, stroke, venous thromboembolism, mortality, cognitive function and quality of life. There were insufficient data to investigate sleep disturbance.

RESULTS

The primary care study and combined clinical cohort studies included 6809 and 18,659 people living with dementia, with 3089 and 914 taking Z-drugs, respectively. New Z-drug use was associated with a greater risk of fractures (hazard ratio 1.40, 95% confidence interval 1.01 to 1.94), with risk increasing with greater cumulative dose (p = 0.002). The hazard ratio for Z-drug use and hip fracture was 1.59 (95% confidence interval 1.00 to 2.53) and for mortality was 1.34 (95% confidence interval 1.10 to 1.64). No excess risks of falls, infections, stroke or venous thromboembolism were detected. Z-drug use also did not have an impact on cognition, neuropsychiatric symptoms, disability or quality of life.

LIMITATIONS

Primary care study - possible residual confounding because of difficulties in identifying patients with sleep disturbance and by dementia severity. Clinical cohort studies - the small numbers of people living with dementia taking Z-drugs and outcomes not necessarily being measured before Z-drug initiation restricted analyses.

CONCLUSIONS

We observed a dose-dependent increase in fracture risk, but no other harms, with Z-drug use in dementia. However, multiple outcomes were examined, increasing the risk of false-positive findings. The mortality association was unlikely to be causal. Further research is needed to confirm the increased fracture risk. Decisions to prescribe Z-drugs may need to consider the risk of fractures, balanced against the impact of improved sleep for people living with dementia and that of their carers. Our findings suggest that when Z-drugs are prescribed, falls prevention strategies may be needed, and that the prescription should be regularly reviewed.

FUTURE WORK

More research is needed on safe and effective management strategies for sleep disturbance in people living with dementia.

STUDY REGISTRATION

This study is registered as European Union electronic Register of Post-Authorisation Studies (EU PAS) 18006.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 1. See the NIHR Journals Library website for further project information.

Next day effects after nighttime treatment with zolpidem: a review

The purpose of this review was to analyze the literature for potential next-day residual effects of zolpidem, a non-benzodiazepine hypnotic, following nighttime administration. Based on more than 30 international clinical trials involving more than 2,600 subjects/patients, it can be concluded that at the recommended doses of zolpidem 10 mg for adults and zolpidem 5 mg for the elderly, at single or repeated dosing, in healthy subjects or insomniac patients, zolpidem appears to induce minimal next-day residual effects. As for all sedative hypnotics, zolpidem is indicated for the short-term treatment of insomnia and is recommended to be taken only when the patient is able to get a full night's sleep before resuming usual activities.

Sleep Disturbances in Chronic Pain: Neurobiology, Assessment, and Treatment in Physical Therapist Practice

Among people with chronic pain, insomnia is highly prevalent, closely related to the mechanism of central sensitization, characterized by low-grade neuroinflammation, and commonly associated with stress or anxiety; in addition, it often does not respond effectively to drug treatments. This review article applies the current understanding of insomnia to clinical practice, including assessment and conservative treatment of insomnia in people with chronic pain. Cognitive-behavioral therapy for insomnia can be efficacious for improvements in sleep initiation, sleep maintenance, perceived sleep quality, and pain interference with daily functioning in people with chronic pain. A recent systematic review concluded that with additional training, physical therapist-led cognitive-behavioral interventions are efficacious for low back pain, allowing their implementation within the field. Cognitive-behavioral therapy for insomnia, as provided to people with chronic pain, typically includes education, sleep restriction measures, stimulus control instructions, sleep hygiene, and cognitive therapy.

Efficacy and Safety of the Traditional Herbal Medicine, Gamiguibi-tang, in Patients With Cancer-Related Sleep Disturbance: A Prospective, Randomized, Wait-List-Controlled, Pilot Study

Background: Sleep disturbance is the second most bothersome symptom in patients with cancer, and it can significantly impair their quality of life. The aim of this study was to investigate the efficacy and safety of the traditional herbal medicine Gamiguibi-tang (GGBT) in patients with cancer-related sleep disturbance. Methods: We conducted a prospective, randomized, wait-list-controlled, open-label pilot clinical trial on cancer-related sleep disturbance. Patients with cancer experiencing poor sleep quality with a Pittsburgh Sleep Quality Index of at least 6 were randomly assigned to the GGBT and wait-list groups to receive GGBT and conventional care, respectively, for 2 weeks. The primary endpoint was the Insomnia Severity Index (ISI) score. Fatigue, depression, and cognitive impairment were assessed as the secondary endpoints by using the Brief Fatigue Inventory (BFI), Beck Depression Inventory (BDI), and Montreal Cognitive Assessment (MoCA). Results: Thirty participants who met the eligibility criteria were enrolled. Sleep disturbance assessed using the ISI improved significantly more in the GGBT group than in the wait-list group (−5.5 ± 4.4 vs 0.1 ± 1.1, P < .001). Fatigue level determined using the BFI also improved significantly more in the GGBT group than in the wait-list group (−0.8 ± 0.8 vs 0.0 ± 0.3, P = .002). The BDI and MoCA scores showed no significant changes. Adverse events were reported in two patients in the GGBT group and consisted of mild dyspepsia and mild edema. Conclusion: GGBT may be a potential treatment option for cancer-related sleep disturbance. Further research is needed to investigate the efficacy and safety of GGBT.

Book Review: Insomnia following Traumatic Brain Injury: A Review

Sleep disturbances after a traumatic brain injury (TBI) have received very little scientific attention despite the fact that several studies indicate that they may occur in 30% to 70% of patients. For individuals with TBI, problems falling asleep or maintaining sleep can exacerbate other symptoms such as pain, cognitive deficits, fatigue, or irritability. Sleep disturbances can thus compromise the rehabilitation process and the ability to return to work. This article reviews the evidence on the epidemiology, etiology, and treatment of insomnia in the context of TBI and proposes areas for future research. Prevalence estimates of insomnia complaints in TBI patients are summarized. Potential etiological factors (i.e., lesions to the nervous system, anxiety) and possible consequences of insomnia (i.e., fatigue, cognitive problems) in the context of TBI are discussed. Finally, pharmacological and psychological treatments previously shown effective to treat insomnia in healthy individuals are discussed as valuable treatment options for TBI patients. Increased knowledge about the high prevalence, diagnosis, and potential etiological factors of insomnia following TBI may promote a better identification, evaluation, and treatment of sleeping difficulties in this population.

Hypnotic drug risks of mortality, infection, depression, and cancer: but lack of benefit

This is a review of hypnotic drug risks and benefits, reassessing and updating advice presented to the Commissioner of the Food and Drug Administration (United States FDA). Almost every month, new information appears about the risks of hypnotics (sleeping pills). The most important risks of hypnotics include excess mortality, especially overdose deaths, quiet deaths at night, infections, cancer, depression and suicide, automobile crashes, falls, and other accidents, and hypnotic-withdrawal insomnia. Short-term use of one-two prescriptions is associated with greater risk per dose than long-term use. Hypnotics have usually been prescribed without approved indication, most often with specific contraindications, but even when indicated, there is little or no benefit. The recommended doses objectively increase sleep little if at all, daytime performance is often made worse, not better, and the lack of general health benefits is commonly misrepresented in advertising. Treatments such as the cognitive behavioral treatment of insomnia and bright light treatment of circadian rhythm disorders offer safer and more effective alternative approaches to insomnia.

Hypnotic drug risks of mortality, infection, depression, and cancer: but lack of benefit

This is a review of hypnotic drug risks and benefits, reassessing and updating advice presented to the Commissioner of the Food and Drug Administration (United States FDA). Almost every month, new information appears about the risks of hypnotics (sleeping pills). This review includes new information on the growing USA overdose epidemic, eight new epidemiologic studies of hypnotics' mortality not available for previous compilations, and new emphasis on risks of short-term hypnotic prescription. The most important risks of hypnotics include excess mortality, especially overdose deaths, quiet deaths at night, infections, cancer, depression and suicide, automobile crashes, falls, and other accidents, and hypnotic-withdrawal insomnia. The short-term use of one-two prescriptions is associated with greater risk per dose than long-term use. Hypnotics are usually prescribed without approved indication, most often with specific contraindications, but even when indicated, there is little or no benefit. The recommended doses objectively increase sleep little if at all, daytime performance is often made worse, not better, and the lack of general health benefits is commonly misrepresented in advertising. Treatments such as the cognitive behavioral treatment of insomnia and bright light treatment of circadian rhythm disorders might offer safer and more effective alternative approaches to insomnia.

Hypnotic drug risks of mortality, infection, depression, and cancer: but lack of benefit

This is a review of hypnotic drug risks and benefits. Almost every month, new information appears about the risks of hypnotics (sleeping pills). The most important risks of hypnotics include excess mortality (especially overdose deaths, quiet deaths at night, and suicides), infections, cancer, depression, automobile crashes, falls, other accidents, and hypnotic-withdrawal insomnia. Short-term use of one-two prescriptions is associated with even greater risk per dose than long-term use. Hypnotics have usually been prescribed without approved indication, most often with specific contraindications, but even when indicated, there is little or no benefit. The recommended doses objectively increase sleep little if at all, daytime performance is often made worse (not better) and the lack of general health benefits is commonly misrepresented in advertising. Treatments such as the cognitive behavioral treatment of insomnia and bright light treatment of circadian rhythm disorders offer safer and more effective alternative approaches to insomnia.

Is suvorexant a better choice than alternative hypnotics?

Suvorexant is a novel dual orexin receptor antagonist (DORA) newly introduced in the U.S. as a hypnotic, but no claim of superiority over other hypnotics has been offered.  The manufacturer argued that the 5 and 10 mg starting doses recommended by the FDA might be ineffective.  The manufacturer's main Phase III trials had not even included the 10 mg dosage, and the 5 mg dosage had not been tested at all in registered clinical trials at the time of approval.  Popular alternative hypnotics may be similarly ineffective, since the FDA has also reduced the recommended doses for zolpidem and eszopiclone.  The "not to exceed" suvorexant dosage of 20 mg does slightly increase sleep.  Because of slow absorption, suvorexant has little effect on latency to sleep onset but some small effect in suppressing wakening after sleep onset and in improving sleep efficiency. The FDA would not approve the manufacturer's preferred 40 mg suvorexant dosage, because of concern with daytime somnolence, driving impairment, and possible narcolepsy-like symptoms.  In its immediate benefits-to-risks ratio, suvorexant is unlikely to prove superior to currently available hypnotics—possibly worse—so there is little reason to prefer over the alternatives this likely more expensive hypnotic less-tested in practice.  Associations are being increasingly documented relating hypnotic usage with incident cancer, with dementia risks, and with premature death.  There is some basis to speculate that suvorexant might be safer than alternative hypnotics in terms of cancer, dementia, infections, and mortality.  These safety considerations will remain unproven speculations unless adequate long-term trials can be done that demonstrate suvorexant advantages.

Cognitive and behavioral treatment options for insomnia

Insomnia is a costly disorder that affects a significant number of people. In many cases, insomnia is comorbid with other illnesses, which complicates its diagnosis and treatment. Most often it is treated with medication; however, patients are not always safe using hypnotics, and medication does not attack the source of the disorder. Cognitive behavioral therapies are better for long-term treatment because they address factors causing or perpetuating insomnia, as opposed to treatments that focus on symptoms. This article examines various nonpharmacological treatments for insomnia. In addition, because circadian rhythm disorders may exhibit symptoms similar to insomnia, there is also a brief overview of 2 common circadian rhythm disorders, delayed sleep phase syndrome and advanced sleep phase syndrome.

The relationship between hippocampal volume and cognition in patients with chronic primary insomnia

Background and Purpose

Differences in hippocampal volume (HV) were compared between chronic primary insomniacs (PIs) and good sleepers (GSs), and the relationship between HV and memory function in PIs was investigated to clarify the effect of chronic sleep deprivation on brain structure and cognition.

Methods

Twenty PIs (mean age, 50 years; 18 females) and 20 age-, gender-, and education-matched GSs were enrolled. Brain magnetic resonance imaging (MRI) was performed on a 1.5-T MRI scanner. Left and right HV and intracranial volume (ICV) were measured manually. Nighttime polysomnography and neuropsychological testing were also applied to all subjects. Group differences in HV were analyzed and the relationships between HV and sleep questionnaire data, nighttime polysomnography, and neuropsychological findings were evaluated.

Results

Compared to GSs, PIs exhibited significantly increased sleep latency and arousal index and a decreased percentage of REM sleep in nighttime polysomnography, as well as impaired verbal and visual memory, and frontal lobe function. Absolute HV and ICV did not differ significantly between PIs and GSs. In the PIs, right and left HVs were negatively correlated with the duration of insomnia and the arousal index, and positively correlated with the recognition of visual memory. In addition, free recall in verbal memory was positively correlated with left HV in PIs.

Conclusions

These findings suggest that chronic sleep deprivation impairs memory and frontal lobe function, and that a long duration of insomnia and poor sleep quality contribute to a bilateral reduction in HV.

The use of Valeriana officinalis (Valerian) in improving sleep in patients who are undergoing treatment for cancer: a phase III randomized, placebo-controlled, double-blind study (NCCTG Trial, N01C5)

Sleep disorders are a substantial problem for cancer survivors, with prevalence estimates ranging from 23% to 61%. Although numerous prescription hypnotics are available, few are approved for long-term use or have demonstrated benefit in this circumstance. Hypnotics may have unwanted side effects and are costly, and cancer survivors often wish to avoid prescription drugs. New options with limited side effects are needed. The purpose of this trial was to evaluate the efficacy of a Valerian officinalis supplement for sleep in people with cancer who were undergoing cancer treatment. Participants were randomized to receive 450 mg of valerian-or placebo orally 1 hour before bedtime for 8 weeks. The primary end point was area under the curve (AUC) of the overall Pittsburgh Sleep Quality Index (PSQI). Secondary outcomes included the Functional Outcomes of Sleep Questionnaire, the Brief Fatigue Inventory (BFI), and the Profile of Mood States (POMS). Toxicity was evaluated with both self-reported numeric analogue scale questions and the Common Terminology Criteria for Adverse Events (CTCAE), version 3.0. Questionnaires were completed at baseline and at 4 and 8 weeks. A total of 227 patients were randomized into this study between March 19, 2004, and March 9, 2007, with 119 being evaluable for the primary end point. The AUC over the 8 weeks for valerian was 51.4 (SD = 16), while that for placebo was 49.7 (SD = 15), with a P value of 0.6957. A supplemental, exploratory analysis revealed that several fatigue end points, as measured by the BFI and POMS, were significantly better for those taking valerian over placebo. Participants also reported less trouble with sleep and less drowsiness on valerian than placebo. There were no significant differences in toxicities as measured by self-report or the CTCAE except for mild alkaline phosphatase increases, which were slightly more common in the placebo group. This study failed to provide data to support the hypothesis that valerian, 450 mg, at bedtime could improve sleep as measured by the PSQI. However, exploratory analyses revealed improvement in some secondary outcomes, such as fatigue. Further research with valerian exploring physiologic effects in oncology symptom management may be warranted.

Effects of the use of hypnotics on cognition

Hypnotic drugs are intended to induce sedation and promote sleep. As a result, they have deteriorating effects on cognitive performance following intake. Most hypnotics are benzodiazepine receptor agonists which can have effects on memory in addition to their sedative effects. Other sedating drugs, such as histamine H1 antagonists or melatonin agonists, may have less effect on memory and learning. Hypnotics with other mechanisms of action are currently being investigated for efficacy and safety. For patients using hypnotic drugs, the effects on cognition are relevant to the extent that a drug dose affects daytime performance. Use of benzodiazepine hypnotics is associated with increased risk of car accidents and falling. Therefore, most hypnotics are studied to determine whether they produce residual sedation and impairing effects on performance the morning after bedtime use. Experimental studies using a standardized driving test clearly show that some drugs and doses produce severe residual effects, whereas others seem to have no or only minor impairing effects on next-day performance. No hypnotic has been found yet to improve daytime performance. Studies on long-term use of benzodiazepine hypnotics suggest that effects on daytime performance may diminish over time due to tolerance. However, there are also studies showing that performance may improve after discontinuation of chronic benzodiazepine use, which suggests that tolerance may not be complete.

How treatment affects cognitive deficits in patients with sleep disorders: methodological issues and results

Sleep disorders are frequently associated with impaired performance although the type and extent of cognitive deficits varies widely between different types of sleep disorders. Treatment is expected to ameliorate these deficits. However, cognitive functioning and its change with treatment depend on numerous factors. In this chapter we discuss methodological issues, including test selection, and person-specific, task-specific and environmental factors that influence cognitive functioning. In addition, features of study design and sampling strategies are discussed. The chapter ends with a short overview of routes by which treatment may affect cognition in sleep-disordered patients.

Treatment options for insomnia--pharmacodynamics of zolpidem extended-release to benefit next-day performance

BACKGROUND

Insomnia can manifest as difficulty in falling asleep, in maintaining sleep throughout the night, or waking up too early, with symptoms often unpredictably changing over time. Pharmacologic options for insomnia treatment include prescription hypnotics, such as gamma-amino butyric acid-receptor agonists, sedating antidepressants, over-the-counter antihistamines, melatonin-receptor agonists, and alternative therapies. A concern with insomnia medications is the risk of next-day residual effects, which can impair memory and ability to perform certain tasks, such as driving, and may increase the risk of accidents and falls, especially in the elderly.

OBJECTIVES

To describe the impact of current insomnia treatments on next-day performance.

RESULTS

The longer-acting benzodiazepines are associated with next-day "hangover" effects and, as a result, have been largely replaced by agents in the nonbenzodiazepine class, which typically have shorter half-lives. The hypnotic, sedative activities of these classes of drugs depend on variations in binding characteristics to the alpha1 subunit of the gamma-amino butyric acidA-receptor, which inhibits neuronal activity in broad areas of the brain and is found in areas of the brain responsible for sleep/wakefulness and sedation. However, nonbenzodiazepines with a rapid onset of action and short half-life have shown limited efficacy for maintaining sleep throughout the night. These properties have contributed to the development of modified-release formulations. Zolpidem extended-release is a bilayer tablet that retains the fast onset of action of its parent compound zolpidem while extending the duration of hypnotic activity, owing to a slower-release portion of the tablet.

CONCLUSIONS

Based on clinical evidence, the risk of residual next-day effects of zolpidem extended-release is limited, mainly due to the similarly short half-life in its extended-release formulation.

High-glycemic-index carbohydrate meals shorten sleep onset

BACKGROUND

Dietary carbohydrate intake has been shown to increase the plasma concentration of tryptophan, a precursor of serotonin and sleep-inducing agent.

OBJECTIVE

To investigate the role of carbohydrate in sleep induction, we explored the effect of glycemic index (GI) and meal time on sleep in healthy volunteers.

DESIGN

We compared the effect of high- and low-GI carbohydrate-based meals ingested 4 h before bedtime on sleep quality. We also evaluated the effect of the timing of high-GI meals (4 h compared with 1 h) on sleep quality. Twelve healthy men (aged 18-35 y) were administered standard, isocaloric (3212 kJ; 8% of energy as protein, 1.6% of energy as fat, and 90.4% of energy as carbohydrate) meals of either Mahatma (low GI = 50) or Jasmine (high GI = 109) rice 4 h before their usual bedtime. On another occasion, the high-GI meal was given 1 h before bedtime. The participants underwent a familiarization night followed by 3 test nights in random order 1 wk apart.

RESULTS

A significant (P = 0.009) reduction in the mean (+/-SD) sleep onset latency (SOL) was observed with a high-GI (9.0 +/- 6.2 min) compared with a low-GI (17.5 +/- 6.2 min) meal consumed 4 h before bedtime. The high-GI meal given 4 h before bedtime showed a significantly shortened SOL compared with the same meal given 1 h before bedtime (9.0 +/- 6.2 min compared with 14.6 +/- 9.9 min; P = 0.01). No effects on other sleep variables were observed.

CONCLUSIONS

We showed that a carbohydrate-based high-GI meal resulted in a significant shortening of SOL in healthy sleepers compared with a low-GI meal and was most effective when consumed 4 h before bedtime. The relevance of these findings to persons with sleep disturbance should be determined in future trials.

A double-blind, placebo- and flurazepam-controlled investigation of the residual psychomotor and cognitive effects of modified release zolpidem in young healthy volunteers

Short-acting hypnotic drugs, such as zolpidem, have minimal residual effects but may not provide optimal efficacy throughout the night for all insomnia patients. A modified-release formulation of zolpidem, zolpidem-MR, has been developed to overcome this limitation. This was a phase I, double-blind, 3-way crossover, placebo-controlled study to investigate the residual psychomotor and cognitive effects of a single oral dose of zolpidem-MR 12.5 mg in 18 healthy young adults. Flurazepam 30 mg was used as a positive control. No comparison with standard immediate-release zolpidem was made. Five neuropsychological tests and 2 subjective tests were performed 8 hours after dosing. The safety of zolpidem-MR was also investigated. Performance on the Critical Flicker Fusion Frequency test, Choice Reaction Time, Immediate and Delayed Word Recall, and the Compensatory Tracking Task was significantly impaired by flurazepam but not by zolpidem-MR (with the exception of the Compensatory Tracking Task) or placebo. No significant effects were observed on the Digit Symbol Substitution Test. The Leeds Sleep Evaluation Questionnaire showed that both drugs improved the ease of getting to sleep and perceived quality of sleep, whereas only flurazepam significantly impaired the ease of awakening. Neither drug scored significantly better than placebo on the Bond and Lader contentedness scale, but both induced a significant difference in calmness; only flurazepam significantly reduced alertness. The safety profile of zolpidem-MR was comparable to placebo. In conclusion, the study showed the good tolerance of zolpidem-MR in terms of residual neuropsychological effects as well as a beneficial effect on sleep quality in young healthy adults.

Association between memory impairment and insomnia among older adults

Chronic insomnia and memory impairment are both common complaints among older adults. Even so, only a few studies to date have examined the effects of chronic insomnia on memory processes among older people, and the results of these studies are contradictory. Therefore, in the current study we examined whether late-life insomnia is associated with the memory status of older adults. The study population comprised two groups: 50 older adult subjects without sleep disorders, and 23 older adult insomniacs. Memory processing for each of the two groups was evaluated using the Rey Auditory Verbal Learning Test (AVLT). The results demonstrate that chronic insomnia in older adults is associated with impairment in memory. Specifically, we found that older people suffering from late-life insomnia exhibit significantly reduced performance in learning rate and in temporal order judgment as well as significantly reduced resistance to proactive interference. The present findings suggest that late-life insomnia may be one of the factors contributing to the decline in memory processing seen among older people.

Neurobehavioral assessment in toxic injury evaluations

Forensic neurobehavioral evaluations present special validity problems such that standard assumptions, procedures, histories, and fact-finding methods used in treatment settings may be inappropriate and misleading. This article discusses basic issues in assessing the quality and reasonableness of forensic toxic injury evaluations. Topics include selection of test instruments, history, functional assessment, threats to validity, voluntary manipulation of test results, chemophobia, limitations of the state of the art in neuropsychology and neurobehavioral assessment, base rates, and norms. Understanding the roles these topics play in toxic injury evaluations is essential to making informed judgments about the quality of forensic neurobehavioral evaluations.

Pharmocokinetics and pharmacodynamics of single-dose triazolam: electroencephalography compared with the Digit-Symbol Substitution Test

AIMS

To investigate whether the electroencephalogram (EEG) directly reflects the CNS effects of benzodiazepines by evaluating the relation of the EEG to plasma drug concentrations and to Digit-Symbol Substitution Test (DSST) scores after a single dose of triazolam, a representative benzodiazepine agonist.

METHODS

Thirteen healthy male subjects were given 0.375 mg triazolam or placebo in a double-blind crossover study. Plasma samples were collected during 8 h after dosage. Pharmacodynamic effects were measured by DSST and EEG at corresponding times.

RESULTS

Pharmacokinetic parameters for triazolam were consistent with established values. Compared with placebo, triazolam significantly impaired psychomotor performance on the DSST (P < 0.001) and increased beta amplitude on the EEG (P < 0.002). DSST and EEG changes both closely tracked changes in plasma concentrations over time. The changes for the two measures were highly correlated with each other (r =-0.94, P < 0.001) based on aggregate values at individual time points. However, the variations in area under the curve of pharmacodynamic effect vs. time (AUCeffect) measured by either method did not reflect the variations in plasma AUC across individuals. The individual variability in AUCeffect from the EEG was similar to that measured by the DSST.

CONCLUSIONS

Both the EEG and the DSST reflect the central benzodiazepine agonist effects of triazolam. Intrinsic variability in both measures is similar.

Impairment state of cognitive performance and the affecting factors in outpatients following gastrointestinal endoscopy after single-dose diazepam

Diazepam is commonly used as premedicant for endoscopic procedures. Wide interindividual differences have been observed in the residual cognitive effects of the drug after gastrointestinal endoscopy. Our aim was to clarify the major factors, including pharmacokinetic factors, contributing to this wide variation in residual cognitive effect after gastrointestinal endoscopy in the study. Sixty-one outpatients undergoing gastrointestinal endoscopy participated in the study. Cognitive effects were evaluated in the diazepam group (n=52) by the digit symbol substitution test (DSST) twice before and 30 min after an intravenous administration of 5 mg diazepam; in the intervening time gastrointestinal endoscopy was performed. Plasma concentrations of diazepam were determined by HPLC. The control group (n=9) was tested by DSST in the same manner. The cognitive effects according to the change in DSST score was significantly decline in the diazepam group compared with the control group (by 0.2 versus -4.6; P=0.014). This prospective study confirmed that cognition was significantly impaired after gastrointestinal endoscopy by premedication to subjects with 5 mg diazepam. There were very wide variations in change in DSST score. However we could not identify the independent variables that best predicted DSST score difference in a multiple regression analysis for age, plasma albumin level, and plasma diazepam concentration 30 min after intravenous administration. We should pay attention to patients' individual states in cognitive performance following gastrointestinal endoscopy after single-dose diazepam.

In Vivo Pharmacological Characterization of Indiplon, a Novel Pyrazolopyrimidine Sedative-Hypnotic

Indiplon (NBI 34060; N-methyl-N-[3-[3-(2-thienylcarbonyl)-pyrazolo[1,5-alpha]pyrimidin-7-yl]phenyl]acetamide), a novel pyrazolopyrimidine and high-affinity allosteric potentiator of GABA(A) receptor function, was profiled for its effects in rodents after oral administration. In mice, indiplon inhibited locomotor activity (ED(50) = 2.7 mg/kg p.o.) at doses lower than the nonbenzodiazepine hypnotics zolpidem (ED(50) = 6.1 mg/kg p.o.) and zaleplon (ED(50) = 24.6 mg/kg p.o.), a sedative effect that was reversed by the benzodiazepine site antagonist flumazenil. Indiplon inhibited retention in the mouse passive avoidance paradigm over a dose range and with a temporal profile that coincided with its sedative activity. Indiplon, zolpidem, and zaleplon were equally effective in inhibiting locomotor activity in the rat and produced dose-related deficits on the rotarod. In a rat vigilance paradigm, indiplon, zolpidem, and zaleplon produced performance deficits over a dose range consistent with their sedative effects, although indiplon alone showed no significant increase in response latency. Indiplon produced a small deficit in the delayed nonmatch to sample paradigm at a dose where sedative effects became apparent. Indiplon was active in the rat Vogel test of anxiety, but it showed only a sedative profile in the mouse open field test. The pharmacokinetic profile of indiplon in both rat and mouse was consistent with its pharmacodynamic properties and indicated a rapid T(max), short t(1/2), and excellent blood-brain barrier penetration. Therefore, indiplon has the in vivo profile of an efficacious sedative-hypnotic, in agreement with its in vitro receptor pharmacology as a high-affinity allosteric potentiator of GABA(A) receptor function, with selectivity for alpha1 subunit-containing GABA(A) receptors.

Residual effects of hypnotics: epidemiology and clinical implications

The risk of "hangover" effects, e.g. residual daytime sleepiness and impairment of psychomotor and cognitive functioning the day after bedtime administration, is one of the main problems associated with the use of hypnotics. However, the severity and duration of these effects varies considerably between hypnotics and is strongly dependent on the dose administered. This article reviews epidemiological evidence on the effect of hypnotics on patients' risk for accidents such as traffic accidents, falls and hip fractures (i.e. end-points for residual effects). Information on the duration and severity of residual effects of 11 hypnotics (flunitrazepam, flurazepam, loprazolam, lormetazepam, midazolam, nitrazepam, temazepam, triazolam, zaleplon, zolpidem and zopiclone) was derived from expert ratings, a meta-analysis and actual driving studies. Epidemiological studies show that the risks of an accident increase with increasing half-life of the hypnotic, but that the use of hypnotics with a short half-life, such as triazolam, zopiclone and zolpidem, can also be associated with increased risks. A summary of results from experimental studies should enable prescribing clinicians to compare residual effects of the various hypnotics at different doses and select the one considered most favourable in this respect for the individual patient. This information should also enable them to inform patients more adequately about the likelihood and duration of residual effects of a specific hypnotic dose.

Comparison of temazepam 7.5 mg with temazepam 15 mg for the treatment of transient insomnia

OBJECTIVE

To demonstrate the equivalent efficacy of temazepam 7.5 mg and temazepam 15 mg for the treatment of transient insomnia.

RESEARCH DESIGN AND METHODS

This was a double-blind, parallel group, multicenter study. Healthy male and female subjects with previous but not current complaints of transient insomnia were enrolled. Transient insomnia was induced in the sleep laboratory by means of the 'first night' effect and by implementing a 2-h phase advance. The effects of both doses of temazepam on polysomnographic (PSG) measures of sleep were evaluated for one night. Latency to persistent sleep (LPS) and total sleep time (TST) were designated as the primary efficacy endpoints.

RESULTS

One hundred and thirty-one subjects completed the study: 65 received the 7.5-mg dose, and 66 received the 15-mg dose. Treatment groups begin with the lowest effective dose, i.e., 7.5 mg. were well matched based on background demographics. No statistically significant differences between doses were detected for LPS, TST,or any other objective (PSG) measure of sleep. Furthermore, both doses were found to be clinically equivalent for LPS and TST based on predetermined criteria. Temazepam was well tolerated, and no significant differences between doses were found for adverse event (AE) incidence, mean score on the Digit Symbol Substitution Task, or mean scores on questions related to tolerability from the Leeds Sleep Evaluation Questionnaire.

CONCLUSIONS

The 7.5-mg and 15-mg doses of temazepam were equally effective for the treatment of transient insomnia. In keeping with current practice guidelines, initiation of treatment with temazepam for transient insomnia should

Neurobehavioural performance effects of daytime melatonin and temazepam administration

Exogenous melatonin is a potential treatment for circadian disruption and insomnia. Hence, it is important to determine and quantify neurobehavioural performance effects associated with its use. The present study compared neurobehavioural performance following administration of melatonin and the benzodiazepine temazepam, using a within-subjects design. Following a training day, 16 healthy, young subjects (six males, 10 females; mean age +/- SEM, 21.4 +/- 6 years) participated in a 3-day protocol. After sleeping overnight in the laboratory, subjects completed a battery of tests at hourly intervals between 08:00 and 11:00 hours and at two hourly intervals between 13:00 and 17:00 hours. The neurobehavioural performance tasks included: unpredictable tracking, spatial memory, vigilance and logical reasoning. Subjective sleepiness was measured at hourly intervals using a visual analogue scale. At 12:00 h subjects were administered a capsule containing 5 mg melatonin, 10 mg temazepam or placebo, in a randomized, double-blind crossover fashion. A significant drug x time interaction was evident on the unpredictable tracking, spatial memory and vigilance tasks (P < 0.05). Greater changes in performance were evident following temazepam administration than melatonin administration, relative to placebo. Administration of melatonin or temazepam significantly elevated subjective sleepiness levels, relative to placebo (P </= 0.05). The present findings demonstrate that melatonin administration induces a smaller deficit in performance on a range of neurobehavioural tasks than temazepam. Given melatonin's soporific and chronobiotic properties, these results suggest that melatonin may be preferable to benzodiazepines in the management of circadian and sleep disorders.

Nutrition, brain function and cognitive performance

Military interest in the effects of nutritional factors on cognitive function has stimulated considerable research on a variety of food constituents. This paper will review the research on the amino acids tryptophan and tyrosine, caffeine and carbohydrate. It will focus on research that addresses the potential utility of these compounds in military applications, particularly the acute, as opposed to chronic, effects of these substances on cognitive functions such as alertness, vigilance and resistance to stress. Caffeine, the most intensively studied food constituent, has unequivocal beneficial effects on vigilance, and in sleep deprived individuals it enhances other cognitive functions as well. Tryptophan, although it clearly has sedative-like properties, has not been extensively studied by military laboratories for use as a hypnotic, due to safety concerns. Tyrosine has been examined in animal models and human studies, and appears to prevent the substantial decline in various aspects of cognitive performance and mood associated with many kinds of acute stress. Carbohydrate supplementation appears to enhance cognitive performance in soldiers engaged in sustained, intense physical activities that expend high levels of energy.

Safety of zaleplon in the treatment of insomnia

OBJECTIVE

To evaluate the safety of zaleplon, a quick-acting, rapidly eliminated nonbenzodiazepine (non-BZD) hypnotic, as described in clinical investigations of adult and/or elderly subjects.

DATA SOURCES

Published and presented studies evaluating zaleplon, a novel non-BZD, were identified via MEDLINE (1995-July 2001), Current Contents (ISI database), bibliographic reviews, and consultation with sleep specialists who also identified published abstracts containing data not yet published in peer-reviewed journals.

DATA SYNTHESIS

Transient and chronic insomnia are common problems that should be clinically evaluated and appropriately treated. BZDs have been a primary pharmacotherapy for treating insomnia, despite their disadvantages. Newer hypnotics, characterized by increased receptor-binding specificity and favorable pharmacokinetics, provide potentially better alternatives to BZDs. Assessments included residual sedation, psychomotor impairment, or cognitive dysfunction during treatment, as well as the occurrence of rebound insomnia and withdrawal effects after discontinuation of therapy.

CONCLUSIONS

Zolpidem, the first non-BZD hypnotic, appears to have short- and long-term safety profiles similar to those of the BZD triazolam. Zaleplon, a newer non-BZD sleep medication, has a quick onset of action and undergoes rapid elimination, which results in a better safety profile than previously available agents. Additionally, rebound insomnia and other withdrawal effects have not been demonstrated with zaleplon, and the drug is well tolerated in both young and elderly patients. These characteristics may be clinically advantageous for patients who should not receive BZDs.

Residual effects of daytime administration of melatonin on performance relevant to flight

There is a general consensus that melatonin possesses time-dependent hypnotic effects, but there is no information yet whether it has residual effects on neurobehavioral performance, especially after daytime administration. In the present study we investigated the possible residual effects of 3 mg melatonin on performance relevant to flight and on subjective feelings of sleepiness, arousal, activation and affect after a daytime nap, as a function of nap length. Fifteen reserve pilots of the Israeli Air Force participated in the study. The experiment consisted of four sessions during which either melatonin or placebo was administered at 16:00 h. In two conditions, subjects were allowed to sleep for 2 h (17:00-19:00 h) whereas in the other two only a 0.5-h nap was allowed. After the naps they started performing a flight simulator task every 2 h. Sleep efficiency significantly increased and sleep latency significantly decreased in both melatonin conditions compared to placebo. Flight performance was only mildly affected in the 0.5-h nap condition. Subjective assessment of sleepiness significantly differed between the two treatment conditions, only in the 0.5-h nap condition. Subjects felt sleepier 2-4 h after melatonin administration. To conclude, our data suggest that administration of melatonin before a brief daytime nap (about 0.5 h) may be associated with mild residual effects on psychomotor performance and may significantly affect subjective feeling of sleepiness for 2-4 h.

The Importance of Residual Effects When Choosing a Hypnotic: The Unique Profile of Zaleplon

BACKGROUND: Insomnia is a prevalent medical disorder that has significant effects on occupational performance, health, and quality of life. Insomnia places an enormous burden on society through increased visits to physicians, loss of productivity in the workplace, and an increased rate of accidents. An estimated sum of $100 million is spent each year on direct treatment of unresolved insomnia. Physicians need to initiate early effective treatment to prevent development of chronic insomnia and its associated morbidity. Institution of good sleep hygiene practices may be useful in some patients but may not be adequate for resolution of all sleep problems. Behavioral treatments, while effective and durable, are time consuming and not widely utilized in clinical practice. Pharmacotherapy includes benzodiazepine hypnotics, but concerns regarding adverse effects (e.g., residual sedation) prompted the search for safer options. DATA SOURCES: Published and presented studies containing clinical data on zaleplon, a new nonbenzodiazepine sleep medication, were identified via MEDLINE, Current Contents (ISI database), bibliographic reviews, and consultation with sleep specialists. RESULTS: Zaleplon effectively shortens sleep onset time and improves the quality of sleep in patients with insomnia. Whether administered at bedtime or later at night, zaleplon is devoid of residual sedative effects that impair next-day functioning. Follow-up studies evaluating the long-term efficacy and safety of zaleplon showed that decreased time to sleep onset was maintained during therapy lasting up to 52 weeks, without a withdrawal syndrome after discontinuation. CONCLUSION: Insomnia is recurrent and unpredictable in nature. Despite the long-term morbidity of this sleep disorder, research evidence and practice guidelines have not explored long-term use of hypnotics. Many patients could benefit from long-term drug therapy with a sleep medication that is devoid of residual effects and can be taken at bedtime or later as symptoms occur, rather than nightly in anticipation of a sleep problem.

The diagnosis of primary insomnia and treatment alternatives

This review provides information about the diagnosis and treatment of primary insomnia. Several treatment strategies are reviewed including the use of hypnotics, naturopathic remedies and behavioral interventions. We suggest that nonpharmacologic interventions are likely to be the most safe and effective.

Multiple-dose tolerability, pharmacodynamics, and pharmacokinetics of the quinolizinone hypnotic Ro 41-3696 in elderly subjects

The objectives of this double-blind, placebo-controlled study were to assess the multiple-dose tolerability, pharmacodynamics, and pharmacokinetics of the hypnotic agent Ro 41-3696 in elderly men and women (55-75 y of age). On day 1 and days 3-8, doses of 1, 3, 5, and 10 mg were administered sequentially to 4 groups of 10 subjects, 2 of whom received placebo. Psychomotor performance tests (tracking and attention) were conducted just before and at 1.5, 4, and 8 hours after drug intake on days 1, 4, 6, and 8. Memory was assessed at 24 hours after drug intake on days 1 and 8 by recall of a list of 10 words, which had been learned at 2 hours after intake. Ro 41-3696 was well tolerated at all dose levels. One subject dropped out of the study because of a hypersensitive skin reaction during treatment with 10 mg. Performance in both a tracking test and a memory search test was significantly affected by a dose of 10 mg and moderately affected by doses of 3 and 5 mg. The results of the 1-mg dose were indistinguishable from those of placebo. Long-term memory, as assessed by a word learning and recall test, showed the same pattern. Partial tolerance to the impairing effects in the psychometric tests developed over the course of treatment. Pharmacokinetics of both Ro 41-3696 and its O-desethyl metabolite Ro 41-3290 were dose proportional and time independent. Ro 41-3696 was absorbed and eliminated rapidly (time of maximum plasma concentration, approximately 1 hour; elimination half-life, approximately 2 hours). Plasma levels of Ro 41-3290 were higher than those of the parent drug, and it was more slowly eliminated (values for time of maximum plasma concentration and elimination half-life, approximately 2 and approximately 7 hours, respectively).

Insomnia in the context of cancer: a review of a neglected problem

This article reviews the evidence on the diagnosis, epidemiology, etiology, and treatment of insomnia in the context of cancer and proposes several areas for future research. Clinical and diagnostic features of insomnia are described and prevalence estimates of insomnia complaints in cancer patients are summarized. Then, potential etiologic factors (ie, predisposing, precipitating, and perpetuating factors) and consequences of insomnia (ie, psychologic, behavioral, and health impact) in the context of cancer are discussed. Finally, pharmacologic and psychologic treatments previously shown effective to treat insomnia in healthy individuals are discussed as valuable treatment options for cancer patients as well. Because long-term use of hypnotic medications is associated with some risks (eg, dependence), it is argued that psychologic interventions (eg, stimulus control, sleep restriction, cognitive therapy) are the treatment of choice for sleep disturbances in the context of cancer, especially when it has reached a chronic course. However, the efficacy of these treatments has yet to be verified specifically in cancer patients.

Zaleplon shortens subjective sleep latency and improves subjective sleep quality in elderly patients with insomnia. The Zaleplon Clinical Investigator Study Group

Insomnia is a frequent complaint in the elderly population. Hypnotic agents, including benzodiazepines, with longer pharmacological half-lives have been associated with side effects, including residual sedation, memory impairment, and discontinuation effects. Zaleplon is a short-acting (elimination half-life of 1 hour), non-benzodiazepine hypnotic that acts on the benzodiazepine type 1 site of the gamma-aminobutyric acid type A (GABA(A)) receptor complex. The pharmacology and pharmacokinetics of Zaleplon suggest a safety profile that is improved over other hypnotics. The objective of this placebo-controlled study was to evaluate the efficacy and safety of Zaleplon (5 and 10 mg) in elderly (> or =65 years) outpatients with primary insomnia. This was a multicenter, double-blind, randomised, placebo-controlled 2-week outpatient study. Postsleep questionnaires were used to record subjective sleep variables: sleep latency, sleep duration, number of awakenings, and sleep quality. Zaleplon significantly reduced subjective sleep latency during both weeks of the study with both 5- and 10-mg doses. Subjective sleep quality was improved for significantly more patients treated with zaleplon 10 mg than those treated with placebo during both weeks of treatment. There was a weak indication of rebound insomnia after discontinuation of treatment with the 10-mg dose, but no significant difference in common treatment-emergent adverse events across treatment groups. Zaleplon is an effective and safe hypnotic for the treatment of insomnia in the elderly.

Clinical pharmacology of psychotropic drugs

No Abstract

Comparison of the effects of zaleplon, zolpidem, and triazolam on memory, learning, and psychomotor performance

Twenty-four healthy male and female subjects, who participated in this randomized, double-blind, crossover study, received single nighttime doses of zaleplon 10 mg (therapeutic dose), zaleplon 20 mg, zolpidem 10 mg (therapeutic dose), zolpidem 20 mg, triazolam 0.25 mg (positive control), and placebo. Subjective behavioral ratings and psychomotor tests were completed before and 1.25 and 8.25 hours after administration of the study drug. The Immediate and Delayed Word Recall tests and the Digit Span Test were used to assess memory. The Digit-Symbol Substitution Test, Paired Associates Learning Test, and Divided Attention Test were used to assess other cognitive skills. Zaleplon 10 mg did not produce any significant changes in memory or learning compared with placebo. All other active treatments, including zolpidem 10 mg, caused psychomotor impairment at the 1.25-hour test battery. Zolpidem 20 mg (twice the therapeutic dose) produced more psychomotor impairment at the 1.25-hour assessment than did any of the other active treatments, including zaleplon 20 mg. At the 8.25-hour time point, test scores for subjects who received zaleplon 10 mg and 20 mg did not differ from the test scores for those who received placebo. However, cognitive impairment persisted up to the 8.25-hour observation for subjects who were administered triazolam 0.25 mg and zolpidem 20 mg. Adverse events associated with the use of zaleplon were transient and mild-to-moderate in severity. Overall, this study shows that zaleplon is a safe hypnotic that does not affect memory, learning, or psychomotor skills associated with vigilance.

Zaleplon - a review of a novel sedative hypnotic used in the treatment of insomnia

Zaleplon (N-[3-(3-cyanopyrazolo[1,5-a] pyrimidin-7-yl) phenyl]-N-ethyl acetamide) is a non-benzodiazepine recently introduced for clinical use. This agent is indicated for the short-term treatment of insomnia. Preclinical studies have shown that the benzodiazepines triazolam and Ro17-1812 can substitute for zaleplon in animals trained to distinguish zaleplon from saline. The benzodiazepine antagonist flumazenil can antagonise the discriminative stimulus effect of zaleplon. These findings suggest that zaleplon is recognised by animals as a benzodiazepine agent. Zaleplon is active after ip. and oral administration in a variety of motor performance tests, including locomotor activity, rotarod and the loaded grid. Zaleplon has been shown to be active in a number of different anticonvulsant models, including the pentylenetetrazole, isoniazid and electroshock models. The compound is also reported to be active against convulsions induced by bicuculline, picrotoxin and strychnine. Studies in anxiolytic models suggest that zaleplon may have weak anxiolytic activity. From preclinical studies, it appears zaleplon possesses a reduced risk of tolerance compared to triazolam, is less likely to potentiate the effects of ethanol and is unlikely to produce amnestic effects. In man, zaleplon is rapidly absorbed and undergoes extensive presystemic metabolism. The compound has a plasma half-life of approximately one hour and is metabolised primarily via the aldehyde oxidase system to form 5-oxo-zaleplon. This metabolite, along with other minor metabolites formed in vivo, do not appear to contribute to the activity of zaleplon. Metabolites of zaleplon are excreted primarily via the urine. Phase I studies suggest that single daytime doses of zaleplon up to 15 mg are well-tolerated. Short-term impairment of performance occurs when zaleplon is administered during the day at doses epsilon 20 mg. However, given the short half-life of the compound, significant impairment of daytime performance is unlikely if zaleplon is administered at bedtime or shortly after retiring for the evening. Results from Phase II/III studies suggest that zaleplon (5 - 20 mg) produces a dose-dependent reduction in sleep latency in patients suffering from primary insomnia. The clinical efficacy of zaleplon persists for at least four weeks at doses of 10 mg and 20 mg. Studies in patients with a history of drug abuse suggest that the abuse potential of zaleplon (at doses above the therapeutic dose range) is similar to that seen with the benzodiazepine triazolam.

Chronic hypnotic use: deadly risks, doubtful benefit. REVIEW ARTICLE

In the United States, roughly 2/3 of all hypnotic prescriptions go to chronic users, who have taken hypnotics for an average of 5 years or more. Two large prospective epidemiological studies have shown that reported hypnotic use, especially use 30 times per month, is associated with an excess hazard of death. Indeed, use of hypnotics 30 times per month is associated with a similar mortality hazard to smoking 1-2 packs of cigarettes per day. Moreover, the hypnotic user's wish to improve daytime function is usually unfulfilled. The preponderance of evidence is that hypnotics impair performance, cognition and memory, increase the risk of automobile accidents and falls and promote unfavourable changes in personality. Due to tolerance, the sleep-promoting effects of hypnotics appear to be lost with chronic use. With long-term use, there is little controlled evidence that hypnotics produce benefits of any sort. More study of long-term hypnotic effects by public agencies is needed, but available evidence weighs strongly against long-term prescribing.

Effets des benzodiazépines sur la performance cognitive et psychomotrice des personnes âgées souffrant d'insomnie

This study investigates the effects of chronic use of benzodiazepines (BZ) as hypnotics on the neuropsychological performance of older adults with insomnia. Twenty-one older persons who had used BZ on a chronic basis (average duration = 21.7 years) for their sleep difficulties were enrolled in a medication withdrawal program. A neuropsychological evaluation was conducted before and after the taper program. A control group composed of older adults not using BZs and without sleep complaints were also evaluated for comparative purpose. The results showed that prolonged use of BZ produces mild and selective impairments of cognitive and psychomotor performance. However, BZ users subjectively evaluated their own performance much more negatively than good sleepers. The results are discussed in terms of a possible amplification of performance deficits among insomnia patients and also as a tolerance to adverse effects that develops with prolonged utilization of BZ.

The significance and management of persistent primary insomnia: the past, present and future of behavioral insomnia therapies

Persistent primary insomnia (PPI) is a prevalent and potentially serious condition that compromises the functioning, health status, and quality of lives of millions of individuals around the world. This condition is typically perpetuated by a host of psychological and behavioral mechanisms that often require behavioral interventions. Nonetheless, all too commonly, practitioners underestimate the seriousness of this condition or rely too heavily on symptom focused sedative hypnotic therapy for its treatment. Herein we briefly review the epidemiology of PPI and consider the inadequacies of sedative hypnotics for treating this disorder. Subsequently, we provide rationale for the use of behavioral interventions with this condition and we describe the gradual evolution of the currently available behavioral insomnia treatments and consider promising recent developments such as the emergence of cognitive-behavioral and specially tailored, patient-specific approaches. In closing, we consider the potential usefulness of a combined pharmacological/behavioral intervention for PPI and present a number of important research questions to address in future studies of the behavioral insomnia therapies.

The sensitivity of pharmacodynamic tests for the central nervous system effects of drugs on the effects of sleep deprivation

Various methods are used to quantify sedative drug effects, but it is unknown how these surrogate measures relate to clinically relevant sleepiness. This study assessed the sensitivity of different surrogates of sedation to clinically relevant sleepiness induced by sleep deprivation. Nine healthy volunteers completed a balanced three-way cross-over study with 1-week wash-out periods. Adaptive tracking, smooth-pursuit and saccadic eye movements, body sway, digit symbol substitution (DSST), visual analogue scales (VAS) and electroencephalograms (EEG) were evaluated on three occasions: (1) during the day after normal sleep, (2) during wakefulness at night; and (3) during the day after a night of sleep deprivation. VAS of alertness showed a gradual decline at night and a constant average reduction of 38 percent [95% Confidence intervals (CI), 28-47%] during the day after sleep deprivation. Average mood scores diminished by 14 percent (95%, CI 2-24%) during the day after sleep deprivation. Adaptive tracking, saccadic eye movements and body sway tended to deteriorate at night, but overall this was not statistically significant. After a night of sleep deprivation, adaptive tracking decreased by 21 percent (95% CI, 11-30%), saccadic eye movements decreased by 9-10 percent (95% CI, 5-13%/6-15%) and body sway increased by 37 percent (95% CI, 5-79%). In contrast, EEG beta2-amplitudes declined significantly at night by 18 percent (95% CI, 6-29%), without changes during the day after sleep deprivation. Smooth pursuit, DSST and other EEG-amplitudes remained unchanged. These results emphasize that reductions in adaptive tracking, saccadic peak velocity and body sway caused by sedative drugs really reflect sedation. They also provide a level of clinical significance for these surrogates of sedation. EEG parameters and smooth pursuit were unaffected by sleep deprivation, so drug-induced changes in these measures may not reflect sedation in a stricter sense. The motivation and alertness necessary for DSST may overcome mild sedation.