Antidepressants and their effect on sleep

Dorsolateral prefrontal transcranial magnetic stimulation in patients with major depression locally affects alpha power of REM sleep

Sleep alterations are among the most important disabling manifestation symptoms of Major Depression Disorder (MDD). A critical role of sleep importance is also underlined by the fact that its adjustment has been proposed as an objective marker of clinical remission in MDD. Repetitive transcranial magnetic stimulation (rTMS) represents a relatively novel therapeutic tool for the treatment of drug-resistant depression. Nevertheless, besides clinical evaluation of the mood improvement after rTMS, we have no clear understanding of what are the neurophysiological correlates of such treatment. One possible marker underlying the clinical outcome of rTMS in MDD could be cortical changes on wakefulness and sleep activity. The aim of this open-label study was to evaluate the efficacy of a sequential bilateral rTMS treatment over the dorsolateral prefrontal cortex (DLPFC) to improve the mood in MDD patients, and to determine if rTMS can induce changes on the sleep structure, and if those changes can be used as a surrogate marker of the clinical state of the patient. Ten drug-resistant depressed patients participated to ten daily sessions of sequential bilateral rTMS with a low-frequency TMS (1 Hz) over right-DLPFC and a subsequent high-frequency (10 Hz) TMS over left-DLPFC. The clinical and neurophysiological effects induced by rTMS were evaluated, respectively by means of the Hamilton Depression Rating Scale (HDRS), and by comparing the sleep pattern modulations and the spatial changes of EEG frequency bands during both NREM and REM sleep, before and after the real rTMS treatment. The sequential bilateral rTMS treatment over the DLPFC induced topographical-specific decrease of the alpha activity during REM sleep over left-DLPFC, which is significantly associated to the clinical outcome. In line with the notion of a left frontal hypoactivation in MDD patients, the observed local decrease of alpha activity after rTMS treatment during the REM sleep suggests that alpha frequency reduction could be considered as a marker of up-regulation of cortical activity induced by rTMS, as well as a surrogate neurophysiological correlate of the clinical outcome.

Mirtazapine provokes periodic leg movements during sleep in young healthy men

STUDY OBJECTIVES

Recent evidence suggests that certain antidepressants are associated with an increase of periodic leg movements (PLMS) that may disturb sleep. So far, this has been shown in patients clinically treated for depression and in cross-sectional studies for various substances, but not mirtazapine. It is unclear whether antidepressants induce the new onset of PLMS or only increase preexisting PLMS, and whether this is a general property of the antidepressant or only seen in depressed patients. We report here the effect of mirtazapine on PLMS in young healthy men.

DESIGN

Open-labeled clinical trial (NCT00878540) including a 3-week preparatory phase with standardized food, physical activity, and sleep-wake behavior, and a 10-day experimental inpatient phase with an adaptation day, 2 baseline days, and 7 days with mirtazapine.

SETTING

Research institute.

PARTICIPANTS

Twelve healthy young (20-25 years) men.

INTERVENTIONS

Seven days of nightly intake (22:00) of 30 mg mirtazapine.

MEASUREMENTS AND RESULTS

Sleep was recorded on 2 drug-free baseline nights, the first 2 drug nights, and the last 2 drug nights. Eight of the 12 subjects showed increased PLMS after the first dose of mirtazapine. Frequency of PLMS was highest on the first drug night and attenuated over the course of the next 6 days. Three subjects reported transient restless legs symptoms.

CONCLUSIONS

Mirtazapine provoked PLMS in 67% of young healthy males. The effect was most pronounced in the first days. The possible role of serotonergic, noradrenergic and histaminergic mechanisms in mirtazapine-induced PLMS is discussed.

Psychiatric disorders and sleep

There is growing experimental evidence that the relationship between psychiatric disorders and sleep is complex and includes bidirectional causation. This article provides the evidence that supports this point of view, reviewing data on sleep disturbances seen in patients with psychiatric disorders as well as data on the impact of sleep disturbances on psychiatric conditions. Although much has been learned about the psychiatric disorders-sleep relationship, additional research is needed to better understand the relationship. Such work promises to improve comprehension of these phenomena and lead to better treatment for the many patients with sleep disorders and psychiatric disorders.

Psychotropic medication use and association with physical and psychosocial outcomes in nursing home residents

Psychotropic medications are commonly prescribed for older adults living in long-term care settings. Use of these medications has been associated with negative functional outcomes. The purpose of this study was to describe the prevalence of psychotropic medication use among nursing home residents, and to explore the relationship of psychotropic medication use on physical and psychosocial outcomes. A secondary data analysis was done using baseline measures from the Res-Care Intervention Study. The sample included 419 residents from 12 nursing homes. There were 288 participants (69%) who were prescribed at least one psychotropic medication, with 81 participants (19%) receiving antipsychotics, 248 (59%) receiving antidepressants, 50 (12%) receiving anxiolytics and 37 (9%) receiving sedative/hypnotics. Controlling for gender, age and cognition, physical outcomes were significantly lower in residents receiving psychotropic medications (F= 3.2, P= 0.01) compared to those not receiving psychotropic medications. Psychosocial outcomes were significantly lower in those residents receiving psychotropic mediations (F= 2.0, P= 0.04). The findings from this study provide additional support for the prevalence of psychotropic medication use among nursing home residents and suggest that residents receiving psychotropic medications may be less likely to engage in functional activities and experience decreased quality of life.

Effects of MPEP, a selective metabotropic glutamate mGlu5 ligand, on sleep and wakefulness in the rat

Metabotropic glutamate receptors (mGlu) have been implicated in the regulation of physiological and behavioral processes. Pharmacological evidence involves group I mGlu receptors in the regulation of emotional states and antagonism of these receptors has been proposed as a novel class of anxiolytic drugs having also antidepressant effects. Here, the effects of mGlu5 receptor selective modulation on sleep and wake states are explored. 32 male Wistar rats were implanted with electrodes for recording sleep and wake states. 2-Methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP hydrochloride, 5, 10, and 20 mg/kg, i.p.), a potent, selective and systemically active mGlu5 receptor negative allosteric modulator, or vehicle was administered 1 h after the beginning of the light period. Sleep recordings were conducted for 3 h. MPEP (5, 10, and 20 mg/kg) significantly suppressed rapid eye movement (REM) sleep, decreasing the number of episodes and mean episode duration, and increased its latency. A reduction of light and deep slow wave sleep (SWS) latency was observed in the groups receiving 10 or 20 mg/kg, increasing latency to first wakefulness episode. 10 mg/kg of MPEP also increased non rapid eye movement sleep (NREM). The present results suggest that mGlu5 receptors might be involved in sleep regulation, more specifically in REM sleep, and drugs that block these receptors could potentially benefit the treatment of pathologies were REM sleep is enhanced.

Validation of the French version of the Pittsburgh Sleep Quality Index Addendum for posttraumatic stress disorder

BACKGROUND

Sleep disturbances are one of the main complaints of patients with trauma-related disorders. The original Pittsburgh Sleep Quality Index Addendum for PTSD (PSQI-A) is self-report instrument developed to evaluate posttraumatic stress disorder (PTSD)-specific sleep disturbances in trauma-exposed individuals. However, to date, the PSQI-A has not yet been translated nor validated in French.

OBJECTIVE

THE PRESENT STUDY AIMS TO: a) translate the PSQI-A into French, and b) examine its psychometric properties.

METHOD

Seventy-three adult patients (mean age=40.3 [SD=15.0], 75% females) evaluated in a specialized psychotraumatology unit completed the French versions of the PSQI-A, Pittsburgh Sleep Quality Index (PSQI), Hospital Anxiety and Depression Scale (HADS), and Impact Event Scale-Revised (IES-R).

RESULTS

The French version of the PSQI-A showed satisfactory internal consistency, inter-item correlations, item correlations with the total score, convergent validity with PTSD and anxiety measures, and divergent validity with a depression measure.

CONCLUSION

Our findings support the use of the French version of the PSQI-A for both clinical care and research. The French version of the PSQI-A is an important addition to the currently available instruments that can be used to examine trauma-related sleep disturbances among French-speaking individuals.

Antidepressant suppression of non-REM sleep spindles and REM sleep impairs hippocampus-dependent learning while augmenting striatum-dependent learning

Rapid eye movement (REM) sleep enhances hippocampus-dependent associative memory, but REM deprivation has little impact on striatum-dependent procedural learning. Antidepressant medications are known to inhibit REM sleep, but it is not well understood if antidepressant treatments impact learning and memory. We explored antidepressant REM suppression effects on learning by training animals daily on a spatial task under familiar and novel conditions, followed by training on a procedural memory task. Daily treatment with the antidepressant and norepinephrine reuptake inhibitor desipramine (DMI) strongly suppressed REM sleep in rats for several hours, as has been described in humans. We also found that DMI treatment reduced the spindle-rich transition-to-REM sleep state (TR), which has not been previously reported. DMI REM suppression gradually weakened performance on a once familiar hippocampus-dependent maze (reconsolidation error). DMI also impaired learning of the novel maze (consolidation error). Unexpectedly, learning of novel reward positions and memory of familiar positions were equally and oppositely correlated with amounts of TR sleep. Conversely, DMI treatment enhanced performance on a separate striatum-dependent, procedural T-maze task that was positively correlated with the amounts of slow-wave sleep (SWS). Our results suggest that learning strategy switches in patients taking REM sleep-suppressing antidepressants might serve to offset sleep-dependent hippocampal impairments to partially preserve performance. State-performance correlations support a model wherein reconsolidation of hippocampus-dependent familiar memories occurs during REM sleep, novel information is incorporated and consolidated during TR, and dorsal striatum-dependent procedural learning is augmented during SWS.

Circadian and sleep disorder in Huntington's disease

Huntington's disease is a progressive neurological disorder that starts insidiously with motor, cognitive or psychiatric disturbance, and progresses through a distressing range of symptoms to end with a devastating loss of function, both motor and executive. There is a growing awareness that, in addition to cognitive and psychiatric symptoms, there are other important non-motor symptoms in HD, including sleep and circadian abnormalities. It is not clear if sleep-wake changes are caused directly by HD gene-related pathology, or if they are simply a consequence of having a neurodegenerative disease. From a patient point of view, the answer is irrelevant, since sleep and circadian disturbances are deleterious to good daily living, even in neurologically normal people. The assumption should be that, at the very least, sleep and/or circadian disturbance in HD patients will contribute to their symptoms. At worst, they may contribute to the progressive decline in HD. Here I review the state of our understanding of sleep and circadian abnormalities in HD. I also outline a set of simple rules that can be followed to improve the chances of a good night's sleep, since preventing any 'preventable' symptoms is the a logical first step in treating disease. The long-term impact of sleep disruption in HD is unknown. There have been no large-scale systematic studies of in sleep in HD. Furthermore, there has never been a study of the efficacy of pharmaceuticals that are typically used to treat sleep deficits in HD patients. Thus treatment of sleep disturbance in HD is necessarily empirical. A better understanding of the relationship between sleep/circadian abnormalities and HD pathology is needed, if treatment of this aspect of HD is to be optimized.

Association between indicators of disability burden and subsequent depression among older persons

BACKGROUND

Disability is associated with depression in older persons, yet the effect of disability burden on the likelihood of being depressed is uncertain.

METHODS

A total of 754 community-living persons, aged ≥70, underwent monthly assessments in four essential activities of daily living and assessments of depression (yes/no) every 18 months for up to 108 months. Within each 18-month person-interval, participants' disability burden was operationalized as none or any, and according to severity (none, mild, or severe) and chronicity (none, nonchronic, or chronic) given the highest level of severity or chronicity experienced during a given 18-month interval, respectively. A variable combining severity and chronicity (none, nonchronic mild, nonchronic severe, chronic-mild, or chronic-severe) was also created. Using generalized estimating equations, we evaluated the association between each indicator of disability burden and subsequent depression.

RESULTS

Participants who had any versus no disability during the previous 18 months were 65% more likely to experience subsequent depression (OR = 1.65; 95% confidence interval [CI] 1.34, 2.02). Quantifying severity (mild disability vs. none, OR = 1.43; 95% CI: 1.15, 1.79; severe disability vs. none, OR = 2.07; 95% CI 1.56, 2.74) and chronicity (nonchronic disability vs. none, OR = 1.44; 95% CI 1.13, 1.83; chronic disability vs. none, OR = 1.96; 95% CI 1.50, 2.55) indicated increasingly stronger associations with subsequent depression, with the highest likelihood of subsequent depression (OR = 2.42; 95% CI 1.78, 3.30) observed among participants with chronic-severe disability.

CONCLUSIONS

Quantifying the magnitude of disability burden, particularly on the basis of severity and chronicity, provides additional information regarding the likelihood of experiencing subsequent depression among older persons.

Impact of paroxetine on sleep problems in 426 cancer patients receiving chemotherapy: a trial from the University of Rochester Cancer Center Community Clinical Oncology Program

BACKGROUND

Sleep problems are a frequent distressing symptom in cancer patients, yet little is known about their treatment. Sleep problems and depression frequently co-occur, leading healthcare professionals to treat depression with the expectation that sleep problems will also improve. The purpose of this study was to compare the effect of paroxetine to placebo on sleep problems via a secondary data analysis of a RCT designed to compare the effects of paroxetine to placebo on fatigue in cancer patients undergoing chemotherapy. A previously published report found a significant effect of paroxetine on depression in this cohort.

METHODS

A total of 426 patients were randomized following Cycle 2 of chemotherapy to receive either 20mg of paroxetine or placebo. Sleep problems were assessed using questions from the Hamilton Depression Inventory three times during chemotherapy.

RESULTS

A total of 217 patients received paroxetine and 209 received placebo. Significantly fewer patients taking paroxetine reported sleep problems compared to patients on placebo (Paroxetine 79% versus Placebo 88%; p<0.05). These differences remained significant even after controlling for baseline sleep problems and depression (p<0.05).

CONCLUSION

Paroxetine had a significant benefit on sleep problems in both depressed and non-depressed cancer patients. However, rates of sleep problems remained high even among those effectively treated for depression with paroxetine. There is a need to develop and deliver sleep-specific interventions to effectively treat sleep-related side effects of cancer treatments. These findings suggest that sleep problems and depression are prevalent and co-morbid. Cancer progression, its response to treatment, and overall patient survival are intricately linked to host factors, such as inflammatory response and circadian rhythms, including sleep/wake cycles. Sleep problems and depression are modifiable host factors that can influence inflammation and impact cancer progression and quality of life. Future research should focus on discovering the pathogenesis of sleep dysregulation and depression in cancer so that better treatment approaches can be developed to ameliorate these symptoms.

Neuroimmunomodulation in unipolar depression: a focus on chronobiology and chronotherapeutics

The rising burden of unipolar depression along with its often related sleep disturbances, as well as increasing rates of sleep restriction in modern society, make the search for an extended understanding of the aetiology and pathophysiology of depression necessary. Accumulating evidence suggests an important role for the immune system in mediating disrupted neurobiological and chronobiological processes in depression. This review aims to provide an overview of the neuroimmunomodulatory processes involved with depression and antidepressant treatments with a special focus on chronobiology, chronotherapeutics and the emerging field of immune-circadian bi-directional crosstalk. Increasing evidence suggests that chronobiological disruption can mediate immune changes in depression, and likewise, immune processes can mediate chronobiological disruption. This may suggest a bi-directional relationship in immune-circadian crosstalk. Furthermore, given the immunomodulatory effects of antidepressants and chronotherapeutics, as well as their associated beneficial effects on circadian disturbance, we--and others--suggest that these therapeutic agents may exert their chronobiotic effects partially via the neuroimmune system. Further research is required to better elucidate the mechanisms of immune involvement in the chronobiology of depression.

Chronic insomnia

Insomnia is a prevalent complaint in clinical practice that can present independently or comorbidly with another medical or psychiatric disorder. In either case, it might need treatment of its own. Of the different therapeutic options available, benzodiazepine-receptor agonists (BzRAs) and cognitive-behavioural therapy (CBT) are supported by the best empirical evidence. BzRAs are readily available and effective in the short-term management of insomnia, but evidence of long-term efficacy is scarce and most hypnotic drugs are associated with potential adverse effects. CBT is an effective alternative for chronic insomnia. Although more time consuming than drug management, CBT produces sleep improvements that are sustained over time, and this therapy is accepted by patients. Although CBT is not readily available in most clinical settings, access and delivery can be made easier through use of innovative methods such as telephone consultations, group therapy, and self-help approaches. Combined CBT and drug treatment can optimise outcomes, although evidence to guide clinical practice on the best way to integrate these approaches is scarce.

Under-treatment of depression in older persons

BACKGROUND

Due to the cross-sectional design of most existing studies, longitudinal characterization of treatment for depression in older persons is largely unknown.

METHOD

Seven hundred fifty-four men and women (aged 70+ years) underwent monthly assessments of mental health professional use and 18-month assessments of antidepressant medication use and depressive symptoms over 9 years. Scores of ≥20 on the Center for Epidemiological Studies-Depression (CES-D) scale denoted depression. We evaluated trends in depression treatment over time in the entire sample and among the depressed participants. Using generalized linear models, we determined characteristics associated with receiving treatment for depression in these groups and among those with persistent depression.

RESULTS

During the 9-year follow-up period (1998-2007), 339 (45.0%) of the participants reported depression treatment. Over time, antidepressant use alone decreased (p trend<0.001) while treatment with both antidepressants and a mental health professional increased (p trend=0.002). Of the 286 (27.9%) depressed participants, between 43% and 69% did not receive depression treatment during any 18-month interval. 30.5% of the 121 participants with persistent depression did not receive treatment during the study period. Increasing number of years of education, decreasing cognitive status score, and being physically frail were associated with a higher likelihood of receiving treatment in all models.

LIMITATIONS

Pre-baseline depression, pre-baseline treatment, and indication for treatment were unavailable.

CONCLUSIONS

Our findings indicate that the profile of treatment for depression in older persons has changed over time, that depressed older persons, including those with persistent depression, are under-treated, and that patient characteristics influence receipt of treatment.

R278995/CRA0450, a corticotropin-releasing factor (CRF(1)) receptor antagonist modulates REM sleep measures in rats: Implication for therapeutic indication

Abnormalities in the regulation of the hypothalamic stress hormone corticotropin-releasing factor (CRF) are thought to play a critical role in mood disorders. Consequently, CRF receptor antagonists have been proposed as potential novel therapeutic agents of these conditions. Sleep disturbance is common in depressed patients and changed sleep-wake architecture is considered as potential predictor or surrogate marker of response to treatment. The aim of our study was to characterise the effects of oral administration of the corticotropin-releasing factor CRF(1) receptor antagonist R278995/CRA0450 (3 and 10mg/kg) on sleep-wake organization and electroencephalographic (EEG) components in Sprague-Dawley rats, and to determine whether the changes observed in the sleep-EEG pattern resemble those seen with antidepressants. At 3mg/kg, R278995/CRA0450 produced minor changes in sleep behaviour, while an overall reduction in power spectra was observed during deep slow wave sleep. At 10mg/kg, R278995/CRA0450 consistently reduced rapid eye movement (REM) sleep (-75.4%) and increased the REM sleep onset latency (+67%, 92.1±4.9min for vehicle vs. 153.8±24min for R278995/CRA0450), in the absence of systematic changes in spectral EEG pattern, which are characteristic anti-depressant-like effects. These findings in rats indicate that the corticotropin-releasing factor CRF(1) receptor antagonist R278995/CRA0450 is centrally active under standard conditions as it inhibits REM sleep and promotes wakefulness. The characteristic changes found in the sleep EEG model further support the hypothesis that R278995/CRA0450 could exert a non-sedative, antidepressant-like action.

5-HT(2C) agonists as therapeutics for the treatment of schizophrenia

The 5-HT(2C) receptor is a highly complex, highly regulated receptor which is widely distributed throughout the brain. The 5-HT(2C) receptor couples to multiple signal transduction pathways leading to engagement of a number of intracellular signaling molecules. Moreover, there are multiple allelic variants of the 5-HT(2C) receptor and the receptor is subject to RNA editing in the coding regions. The complexity of this receptor is further emphasized by the studies suggesting the utility of either agonists or antagonists in the treatment of schizophrenia. While several 5-HT(2C) agonists have demonstrated clinical efficacy in obesity (lorcaserin, PRX-000933), the focus of this review is on the therapeutic potential of 5-HT(2C) agonists in schizophrenia. To this end, the preclinical profile of 5-HT(2C) agonists from a neurochemical, electrophysiological, and a behavioral perspective is indicative of antipsychotic-like efficacy without extrapyramidal symptoms or weight gain. Recently, the selective 5-HT(2C) agonist vabicaserin demonstrated clinical efficacy in a Phase II trial in schizophrenia patients without weight gain and with low EPS liability. These data are highly encouraging and suggest that 5-HT(2C) agonists are potential therapeutics for the treatment of psychiatric disorders.

Promotion of non-rapid eye movement sleep and activation of reticular thalamic neurons by a novel MT2 melatonin receptor ligand

Melatonin activates two brain G-protein coupled receptors, MT(1) and MT(2), whose differential roles in the sleep-wake cycle remain to be defined. The novel MT(2) receptor partial agonist, N-{2-[(3-methoxyphenyl) phenylamino] ethyl} acetamide (UCM765), is here shown to selectively promote non-rapid eye movement sleep (NREMS) in rats and mice. The enhancement of NREMS by UCM765 is nullified by the pharmacological blockade or genetic deletion of MT(2) receptors. MT(2), but not MT(1), knock-out mice show a decrease in NREMS compared to the wild strain. Immunohistochemical labeling reveals that MT(2) receptors are localized in sleep-related brain regions, and notably the reticular thalamic nucleus (Rt). Microinfusion of UCM765 in the Rt promotes NREMS, and its systemic administration induces an increase in firing and rhythmic burst activity of Rt neurons, which is blocked by the MT(2) antagonist 4-phenyl-2-propionamidotetralin. Since developing hypnotics that increase NREMS without altering sleep architecture remains a medical challenge, MT(2) receptors may represent a novel target for the treatment of sleep disorders.

Sleep Disturbances in Pediatric Depression

Depressive illness beginning early in life can have serious developmental and functional consequences. Therefore, understanding its etiology and pathophysiology during this developmental stage is critical for developing effective prevention and intervention strategies. There is considerable evidence of sleep alterations in adult major depressive disorder. However, studies in children and adolescents have not found consistent changes in sleep architecture paralleling adult depression. This review article summarizes sleep polysomnography research in early-onset depression, highlighting the factors associated with variable findings across studies. In addition, potential avenues for future research will be suggested in order to develop more comprehensive theoretical models and interventions for pediatric depression.

Clinical relevance of disturbances of sleep and vigilance in major depressive disorder: a review

OBJECTIVE

The primary objective of this article is to provide a concise review of the clinical relevance of sleep and vigilance in major depressive disorder.

DATA SOURCES

PubMed was reviewed (1990-2009) and English-language articles were identified using the key words sleep and depression and sleep and antidepressants. Secondary searches included articles cited in sources identified by the primary search.

STUDY SELECTION

The narrative review provides brief descriptions of the normal physiology of sleep and changes associated with depression, as well as the impact of various treatments on these processes.

DATA SYNTHESIS

Although it has long been known that sleep disturbances are an important characteristic of depression, relatively few studies have been conducted with the newer-generation antidepressants. Neither of the most widely used classes of antidepressants, the selective serotonin reuptake inhibitors and the serotonin-norepinephrine reuptake inhibitors, have particularly beneficial effects on sleep and, among the medications that reliably improve sleep efficiency, including mirtazapine and the tricyclic antidepressants, problems with daytime sedation can offset therapeutic benefit. Despite relatively widespread use, trazodone has not been demonstrated to be an effective and safe hypnotic in patients taking other antidepressants. For many patients, ongoing concomitant treatment with benzodiazepines and related drugs is the preferred option, again without convincing empirical support of longer-term efficacy. Among newer and investigational antidepressants, agomelatine shows promise with respect to both overall safety and effects on insomnia, although possible negative effects on liver function warrant further study.

CONCLUSIONS

Sleep disturbances are a significant aspect of depressive syndromes, and relief of insomnia remains an important unmet need in antidepressant therapeutics. Development of a well-tolerated antidepressant medication that rapidly improves sleep maintenance without daytime sedation is a priority for drug development.

Rapid eye movements during sleep in mice: high trait-like stability qualifies rapid eye movement density for characterization of phenotypic variation in sleep patterns of rodents

Background

In humans, rapid eye movements (REM) density during REM sleep plays a prominent role in psychiatric diseases. Especially in depression, an increased REM density is a vulnerability marker for depression. In clinical practice and research measurement of REM density is highly standardized. In basic animal research, almost no tools are available to obtain and systematically evaluate eye movement data, although, this would create increased comparability between human and animal sleep studies.

Methods

We obtained standardized electroencephalographic (EEG), electromyographic (EMG) and electrooculographic (EOG) signals from freely behaving mice. EOG electrodes were bilaterally and chronically implanted with placement of the electrodes directly between the musculus rectus superior and musculus rectus lateralis. After recovery, EEG, EMG and EOG signals were obtained for four days. Subsequent to the implantation process, we developed and validated an Eye Movement scoring in Mice Algorithm (EMMA) to detect REM as singularities of the EOG signal, based on wavelet methodology.

Results

The distribution of wakefulness, non-REM (NREM) sleep and rapid eye movement (REM) sleep was typical of nocturnal rodents with small amounts of wakefulness and large amounts of NREM sleep during the light period and reversed proportions during the dark period. REM sleep was distributed correspondingly. REM density was significantly higher during REM sleep than NREM sleep. REM bursts were detected more often at the end of the dark period than the beginning of the light period. During REM sleep REM density showed an ultradian course, and during NREM sleep REM density peaked at the beginning of the dark period. Concerning individual eye movements, REM duration was longer and amplitude was lower during REM sleep than NREM sleep. The majority of single REM and REM bursts were associated with micro-arousals during NREM sleep, but not during REM sleep.

Conclusions

Sleep-stage specific distributions of REM in mice correspond to human REM density during sleep. REM density, now also assessable in animal models through our approach, is increased in humans after acute stress, during PTSD and in depression. This relationship can now be exploited to match animal models more closely to clinical situations, especially in animal models of depression.

Drug-induced sleep: theoretical and practical considerations

Faithful replication of normal sleep through medications--can it be achieved? Departure from normal sleep with the use of drugs--when is it desired? Answers to these questions depend on accurate understanding of sleep and on concrete criteria upon which to define it. Since these elements are evolving sciences, as yet incompletely known, one might take a nihilistic approach that we simply cannot judge whether we have successfully replicated sleep, since we do not fully grasp what sleep is or what it does. To address these potential obstacles, our article is written in two sections. The first addresses theoretical considerations for how medications might be seen in the larger framework of sleep. The purpose of this section is to inform readers about key issues in evaluating whether a drug has sufficient data to persuasively argue it is re-creating sleep. (We hope that researchers interested in conducting studies, or critical readers of the drug-study literature, might find this section particularly useful.) The second section of this article approaches exemplary, current concepts of pharmacologic manipulation of sleep, organized by disorders as articulated by the International Classification of Sleep Disorders (2005). This second section will combine practical knowledge of clinical sleep medicine, with emphasis on contemporary knowledge about molecular mechanisms that are felt to underlie some of these phenomena. We recognize that our collective knowledge about sleep will advance in the coming years. We hope that this article serves to facilitate that advance.

The Memory Function of Noradrenergic Activity in Non-REM Sleep

There is a long-standing assumption that low noradrenergic activity during sleep reflects mainly the low arousal during this brain state. Nevertheless, recent research has demonstrated that the locus coeruleus, which is the main source of cortical noradrenaline, displays discrete periods of intense firing during non-REM sleep, without any signs of awakening. This transient locus coeruleus activation during sleep seems to occur in response to preceding learning-related episodes. In the present study, we manipulate noradrenergic activity during sleep in humans with either the α2-autoreceptor agonist clonidine or the noradrenaline reuptake inhibitor reboxetine. We show that reducing noradrenergic activity during sleep, but not during wakefulness, impairs subsequent memory performance in an odor recognition task. Increasing noradrenergic availability during sleep, in contrast, enhances memory retention. We conclude that noradrenergic activity during non-REM sleep interacts with other sleep-related mechanisms to functionally contribute to off-line memory consolidation.

Depressive symptoms and functional transitions over time in older persons

OBJECTIVE

The authors determined the association between clinically significant depressive symptoms, often referred to as depression, and subsequent transitions between no disability, mild disability, severe disability, and death.

DESIGN

Prospective cohort study.

SETTING

General community in greater New Haven, Connecticut, from March 23, 1998, to December 31, 2008.

PARTICIPANTS

Seven hundred fifty-four persons, age 70 years or older.

MEASUREMENTS

Monthly assessments of disability in essential activities of daily living and assessments of depressive symptoms every 18 months using a short-form of the Center for Epidemiologic Studies of Depression Scale for up to 129 months.

RESULTS

Depressed participants were more likely than those who were nondepressed to transition from a state of no disability to mild (HR = 1.52; 95% CI: 1.25-1.85) and severe disability (HR = 1.57; 95% CI: 1.22-2.01), and from a state of mild disability to severe disability (HR = 1.33; 95% CI: 1.06-1.65), and were less likely to transition from a state of mild disability to no disability (HR = 0.69; 95% CI: 0.57-0.85) and from a state of severe disability to no disability (HR = 0.50; 95% CI: 0.31-0.79).

CONCLUSIONS

Depressive symptoms are associated with transitions into and out of disabled states and with increased likelihood of transitioning from mild to severe disability. More broadly, our findings underscore the complexity of the relationship between depressive symptoms and disability. Future work is needed to evaluate the likely reciprocal relationship between depression and functional transitions in older persons.

Barriers to achieving treatment goals: a focus on sleep disturbance and sexual dysfunction

BACKGROUND

Patients who meet the criteria for a major depressive episode experience a constellation of symptoms, and different symptom configurations may reflect distinct underlying neurological disturbances. Similarly, the differing receptor profiles of the various antidepressants may explain relatively low remission rates and persistent symptoms even after remission. In particular, depressed patients frequently display altered circadian rhythms, sleep disturbances, and diurnal mood variation. Exploring treatments that can restore mood while having a positive impact on circadian rhythms and sleep would greatly improve the ability to treat this core features of depression.

METHODS

The mechanisms of action of the various classes of antidepressants, their effects on sleep and issues beyond sleep, including sexual dysfunction, are explored, along with questions relating to adherence.

RESULTS

Unfortunately, persistent sleep problems are among the most difficult-to-treat residual symptoms of depression. Many of the currently available antidepressants have adverse effects on circadian processes, including sleep, and may actually worsen sleep problems. Tolerability is also an enduring issue; SSRI and SNRI antidepressants are associated with central nervous sysytem and gastrointestinal effects, sexual side effects and suicidality. Improved drug tolerability would not only minimize distressing adverse effects, but would also improve adherence, thus maximizing the chances of successful treatment.

CONCLUSIONS

The complexity of managing a major depressive episode is well illustrated by sleep disturbance and sexual dysfunction, two core symptoms of MDD that may also be caused or exacerbated by antidepressant therapy. Future antidepressants should alleviate symptoms without adversely affecting sleep or sexual function.

Sleep problems in Parkinson’s disease patients

SUMMARY Parkinson’s disease (PD) patients demonstrate a variety of sleep/wake complaints. Some of these are associated with dopaminergic dysfunction, some presumed to arise from nondopaminergic PD pathology, some from PD treatments and, in some, the etiologies are multifactorial or unknown. Optimal management of sleep/wake problems requires a good understanding of sleep/wake principals in the PD population, as there are few controlled trials to dictate therapy. In this article, we review the main causes of sleep/wake disorders in PD patients, namely sleep fragmentation, excessive daytime sleepiness, restless legs syndrome, periodic limb movement of sleep, rapid eye movement sleep behavioral disorder and sleep apnea. Available therapies and management recommendations for each disorder are given particular emphasis.

Can online consumers contribute to drug knowledge? A mixed-methods comparison of consumer-generated and professionally controlled psychotropic medication information on the internet

BACKGROUND

Ongoing initiatives to filter online health searches exclude consumer-generated content from search returns, though its inferiority compared with professionally controlled content is not demonstrated. The antidepressant escitalopram and the antipsychotic quetiapine have ranked over the last 5 years as top-selling agents in their respective drug classes. Both drugs have various off-label mental health and non-mental health uses, ranging from the relief of insomnia and migraines to the treatment of severe developmental disorders.

OBJECTIVE

Our objective was to describe the most frequently reported effects of escitalopram and quetiapine in online consumer reviews, to compare them with effects described in professionally controlled commercial health websites, and to gauge the usability of online consumer medication reviews.

METHODS

A stratified simple random sample of 960 consumer reviews was selected from all 6998 consumer reviews of the two drugs in 2 consumer-generated (www.askapatient.com and www.crazymeds.us) and 2 professionally controlled (www.webmd.com and www.revolutionhealth.com) health websites. Professional medication descriptions included all standard information on the medications from the latter 2 websites. All textual data were inductively coded for medication effects, and intercoder agreement was assessed. Chi-square was used to test for associations between consumer-reported effects and website origination.

RESULTS

Consumers taking either escitalopram (n = 480) or quetiapine (n = 480) most frequently reported symptom improvement (30.4% or 146/480, 24.8% or 119/480) or symptom worsening (15.8% or 76/480, 10.2% or 49/480), changes in sleep (36% or 173/480, 60.6% or 291/480) and changes in weight and appetite (22.5% or 108/480, 30.8% or 148/480). More consumers posting reviews on consumer-generated rather than professionally controlled websites reported symptom worsening on quetiapine (17.3% or 38/220 versus 5% or 11/220, P < .001), while more consumers posting on professionally controlled websites reported symptom improvement (32.7% or 72/220 versus 21.4% or 47/220, P = .008). Professional descriptions more frequently listed physical adverse effects and warnings about suicidal ideation while consumer reviews emphasized effects disrupting daily routines and provided richer descriptions of effects in context. The most recent 20 consumer reviews on each drug from each website (n = 80) were comparable to the full sample of reviews in the frequency of commonly reported effects.

CONCLUSION

Consumer reviews and professional medication descriptions generally reported similar effects of two psychotropic medications but differed in their descriptions and in frequency of reporting. Professional medication descriptions offer the advantage of a concise yet comprehensive listing of drug effects, while consumer reviews offer greater context and situational examples of how effects may manifest in various combinations and to varying degrees. The dispersion of consumer reviews across websites limits their integration, but a brief browsing strategy on the two target medications nonetheless retrieved representative consumer content. Current strategies for filtering online health searches to return only trusted or approved websites may inappropriately address the challenge to identify quality health sources on the Internet because such strategies unduly limit access to an entire complementary source for health information.

Fentanyl-trazodone-paracetamol triple drug combination: multimodal analgesia in a mouse model of visceral pain

Multimodal or balanced analgesia is commonly used in the management of acute and chronic pain in humans, in order to achieve the best analgesic/safety profile. Here, by using a model of visceral acute tonic pain, the acetic acid-induced writhing test of mice, we show a synergistic interaction between fentanyl, trazodone and paracetamol on the inhibition of nociception. First of all, once assessed that all drugs induced dose-related antinociceptive effects, they were mixed in fixed ratio (1:1) combinations and a synergistic drug-drug interaction was obtained in all circumstances. Thereafter, we assayed the effects of the triple combination of fentanyl-trazodone-paracetamol and it was demonstrated that they displayed a potent synergistic interaction on the inhibition of acetic acid-mediated nociception. Interestingly, drug dosage reduction permitted to reduce the incidence of possible adverse effects, namely exploratory activity and motor coordination, thus it was demonstrated that it improved the benefit/risk profile of such treatment. Afterwards, we attempted to elucidate the mechanism of action of such interaction, by means of the non-selective opioid receptor antagonist naloxone. Interestingly, naloxone completely antagonized the antinociceptive effects of fentanyl, and it also partially reversed paracetamol and trazodone mediated analgesia. Furthermore, when naloxone was co-administered with the triple-drug treatment it blocked the previously observed enhanced antinociceptive effects of the combination. Thus, these results indicated that the endogenous opioid system played a main role in the present drug-drug interaction. Overall, the triple combination of fentanyl-trazodone-paracetamol induced a potent synergistic antinociceptive effect, which could be of interest for optimal multimodal clinical analgesia.

Residual effects of esmirtazapine on actual driving performance: overall findings and an exploratory analysis into the role of CYP2D6 phenotype

INTRODUCTION

Esmirtazapine is evaluated as a novel drug for treatment of insomnia.

PURPOSE

The present study was designed to assess residual effects of single and repeated doses of esmirtazapine 1.5 and 4.5 mg on actual driving in 32 healthy volunteers in a double-blind, placebo-controlled study. Treatment with single doses of zopiclone 7.5 mg was included as active control.

METHODS

Treatments were administered in the evening. Driving performance was assessed in the morning, 11 h after drug intake, in a standardized on-the-road highway driving test. The primary study parameter was standard deviation of lateral position (SDLP), a measure of "weaving". All subjects were subjected to CYP2D6 phenotyping in order to distinguish poor metabolizers from extensive metabolizers of esmirtazapine.

RESULTS

Overall, esmirtazapine 1.5 mg did not produce any clinically relevant change in SDLP after single and repeated dosing. Driving impairment, i.e., a rise in SDLP, did occur after a single-dose administration of esmirtazapine 4.5 mg but was resolved after repeated doses. Acute driving impairment was more pronounced after both doses of esmirtazapine in a select group of poor metabolizers (N = 7). A single-dose zopiclone 7.5 mg also increased SDLP as expected.

CONCLUSION

It is concluded that single and repeated doses of 1.5 mg esmirtazapine are generally not associated with residual impairment. Single-dose administration of 4.5 mg esmirtazapine was associated with residual impairment that generally resolved after repeated administration. Exploratory analysis in a small group of poor CYP 2D6 metabolizers suggested that these subjects are more sensitive to the impairing effects of esmirtazapine on car driving.

A psychopharmacological treatment algorithm for generalised anxiety disorder (GAD)

Generalised anxiety disorder (GAD) is defined as excessive and uncontrollable worry and anxiety about everyday life situations. It is a chronic disorder, and is associated with substantial somatisation, high rates of comorbid depression and other anxiety disorders, and significant disability. The evidence base for pharmacotherapy and psychotherapy has continued to grow, and a wide range of drug choices for GAD now exists. Current guidelines for GAD generally restrict themselves to presentation of the evidence for various treatments, which, as a result, generally do not offer detailed discussion or recommendation of strategies beyond the first level of treatment, or take into account the individual circumstances of the patient. Thus, there is a lack of algorithm-based treatment guidelines for GAD. Our aim is, therefore, to present an algorithm for the psychopharmacologic management of GAD, intended for all clinicians who treat patients with GAD, where issues of pharmacotherapy are under consideration. We also hope that these GAD algorithms and other guidelines can help to identify high-priority areas that need further study. In this algorithm, we provide a sequenced approach to the pharmacotherapy of GAD, taking into account salient symptomatology and comorbidity, levels of evidence and extent of response. Special issues, including comorbidity, insomnia, suicidality, substance abuse, treatment adherence, pregnancy and lactation, cross-cultural issues, use of medication in the elderly, psychosocial treatment and dosing issues are also addressed.

British Association for Psychopharmacology consensus statement on evidence-based treatment of insomnia, parasomnias and circadian rhythm disorders

Sleep disorders are common in the general population and even more so in clinical practice, yet are relatively poorly understood by doctors and other health care practitioners. These British Association for Psychopharmacology guidelines are designed to address this problem by providing an accessible up-to-date and evidence-based outline of the major issues, especially those relating to reliable diagnosis and appropriate treatment. A consensus meeting was held in London in May 2009. Those invited to attend included BAP members, representative clinicians with a strong interest in sleep disorders and recognized experts and advocates in the field, including a representative from mainland Europe and the USA. Presenters were asked to provide a review of the literature and identification of the standard of evidence in their area, with an emphasis on meta-analyses, systematic reviews and randomized controlled trials where available, plus updates on current clinical practice. Each presentation was followed by discussion, aimed to reach consensus where the evidence and/or clinical experience was considered adequate or otherwise to flag the area as a direction for future research. A draft of the proceedings was then circulated to all participants for comment. Key subsequent publications were added by the writer and speakers at draft stage. All comments were incorporated as far as possible in the final document, which represents the views of all participants although the authors take final responsibility for the document.

Polysomnographic and subjective profiles of sleep continuity before and after mindfulness-based cognitive therapy in partially remitted depression

OBJECTIVES

To examine whether mindfulness meditation (MM) was associated with changes in objectively measured polysomnographic (PSG) sleep profiles and to relate changes in PSG sleep to subjectively reported changes in sleep and depression within the context of a randomized controlled trial. Previous studies have indicated that mindfulness and other forms of meditation training are associated with improvements in sleep quality. However, none of these studies used objective PSG sleep recordings within longitudinal randomized controlled trials of naïve subjects.

METHODS

Twenty-six individuals with partially remitted depression were randomized into an 8-week Mindfulness-Based Cognitive Therapy (MBCT) course or a waitlist control condition. Pre-post measurements included PSG sleep studies and subjectively reported sleep and depression symptoms.

RESULTS

According to PSG sleep, MM practice was associated with several indices of increased cortical arousal, including more awakenings and stage 1 sleep and less slow-wave sleep relative to controls, in proportion to amount of MM practice. According to sleep diaries, subjectively reported sleep improved post MBCT but not above and beyond controls. Beck Depression Inventory scores decreased more in the MBCT group than controls. Improvements in depression were associated with increased subjective sleep continuity and increased PSG arousal.

CONCLUSIONS

MM is associated with increases in objectively measured arousal during sleep with simultaneous improvements in subjectively reported sleep quality and mood disturbance. This pattern is similar to the profiles of positive responders to common antidepressant medications.

[Disturbances of slow-wave sleep and psychiatric disorders]

Slow-wave sleep is defined as sleep stages 3 and 4 that characteristically show slow delta EEG activity during polysomnography. The percentage of slow-wave sleep normally declines with age. Sleep disorders are a common symptom of many psychiatric disorders. In polysomnographic recordings they mostly manifest as disturbances of sleep continuity. In some disorders changes in REM sleep are also found. A reduction of slow-wave sleep has most often been described in patients with depression and addictive disorders. More recent research implicates slow-wave sleep as an important factor in memory consolidation, especially the contents of declarative memory. Psychotropic drugs influence sleep in different ways. Hypnotic substances can reduce the deep sleep stages (e.g. benzodiazepines), whereas 5-HT2C antagonists increase the percentage of slow-wave sleep. Whether a selective impairment/alteration of slow-wave sleep is clinically relevant has not yet been proved.

Agomelatine in the treatment of major depressive disorder: potential for clinical effectiveness

To demonstrate the clinical effectiveness of an antidepressant drug requires evidence beyond short- and long-term efficacy, including a favourable adverse-effect profile and sustained treatment adherence. Under these conditions, patients should experience enhanced social and functional outcomes. The novel antidepressant agomelatine, a melatonergic MT(1)/MT(2) receptor agonist with serotonin 5-HT(2C) receptor antagonist activity, displays antidepressant efficacy with a favourable adverse-effect profile that is associated with good patient adherence. Specifically, agomelatine has demonstrated significant short-term (6-8 weeks) and sustained (6 months) antidepressant efficacy relative to placebo, as well as evidence of relapse prevention (up to 10 months). In head-to-head comparative studies with venlafaxine and sertraline, there was evidence of early (at 1-2 weeks) and sustained (at 6 months) advantages for agomelatine. In addition to evidence of early efficacy, agomelatine also restored disturbed sleep-wake patterns early in treatment. There was no evidence of antidepressant-induced sexual dysfunction, weight gain or discontinuation-emergent symptoms. Agomelatine has demonstrated a range of properties that suggest it could offer advantages over current treatments for major depressive disorder, although further comparative trials are still required, as is evidence from real-world clinical practice.

The effect of selective serotonin reuptake inhibitors in healthy subjects. A systematic review

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) show antidepressant properties in many patients with a diagnosis of depression. An understanding of the underlying mechanisms of the effect of SSRIs in healthy patients may lead to an understanding of the yet unclear pathophysiology of depression. Recent reviews of studies investigating the effect of SSRIs in healthy persons conclude that the results are inconsistent and that--in relation to a wide range of outcomes--the effect of SSRIs is limited; however, reasons for the inconsistencies are poorly studied.

AIMS AND METHODS

To investigate whether methodological artefacts can explain the diverging findings, we conducted a systematic review of all randomized multiple-dose, placebo-controlled trials on the effect of treatment by SSRI for at least a week in healthy persons published before January 2009.

RESULTS

We identified 33 trials, investigating six SSRIs and 163 outcome tests. The effect of SSRI showed divergence presumably related to methodological issues. Specifically, it is likely that the majority of studies included a mix of healthy persons with and without a family history of affective disorders. Few presented information on factors that may influence outcomes such as age, gender, family history of psychiatric disorder, drug levels and ethnicity. No study fulfilled principles of conducting and reporting randomized controlled trials, according to the CONSORT Statement guidelines.

CONCLUSIONS

It is unclear whether the effect of SSRIs in healthy persons may lead to an understanding of the pathophysiology of depression, since the present evidence is divergent and may be severely influenced by a number of methodological drawbacks.

Impact of the novel antidepressant agomelatine on disturbed sleep-wake cycles in depressed patients

BACKGROUND

Disturbance of sleep-wake cycles is common in major depressive disorder (MDD), usually as insomnia, but also as hypersomnia or reduced daytime alertness. Agomelatine, an MT(1) and MT(2) receptor agonist and 5-HT(2C) receptor antagonist, represents a novel approach in MDD, with proven antidepressant efficacy and a positive impact on the sleep-wake cycle. We review the effects of agomelatine 25/50 mg/day on objective and subjective measures of the sleep-wake cycle in MDD.

SUBJECTIVE MEASURES

Agomelatine improved all aspects of the sleep-wake cycle from as early as 1 week in randomized trials versus selective serotonin reuptake inhibitors and venlafaxine, particularly getting off to sleep and quality of sleep, with an improvement in daytime alertness.

OBJECTIVE MEASURES

Agomelatine's effect on sleep architecture in MDD has been measured by polysomnography (PSG). There were significant improvements in sleep efficiency, slow-wave sleep (SWS), and the distribution of delta activity throughout the night, but no change in amount or latency of rapid eye movement (REM) sleep. Furthermore, the slow-wave sleep was resynchronized to the first sleep cycle of the night.

CONCLUSION

Agomelatine, a novel antidepressant, improves disturbed sleep-wake cycles in MDD. The improvement of both nighttime sleep and daytime functioning with agomelatine are promising features of this antidepressant regarding the management of MDD.

The effect of melatonergic and non-melatonergic antidepressants on sleep: weighing the alternatives

In DSM-IV the occurrence of disturbed sleep is one of the principal diagnostic criteria for major depressive disorder (MDD). Further, there is evidence of reciprocity between the two conditions such that, even in the absence of current depressive symptoms, disturbed sleep often predicts their development. The present review discusses the effects of antidepressants on sleep and evaluates the use of the recently developed melatonin agonist-selective serotonin antagonists on sleep and depression. Although many antidepressants such as the tricyclics, monoamine oxidase inhibitors, serotonin-norepinephrine reuptake inhibitors, several serotonin receptor antagonists and selective serotonin reuptake inhibitors (SSRIs) have all been found successful in treating depression, their use is often associated with a disruptive effect on sleep. SSRIs, currently the most widely prescribed of the antidepressants, are well known for their instigation or exacerbation of insomnia. The recently introduced novel melatonin agonist and selective serotonin antagonist antidepressant, agomelatine, which has melatonin MT(1) and MT(2) receptor agonist and 5-HT(2c) antagonist properties, has been useful in treating patients with MDD. Its rapid onset of action and effectiveness in improving the mood of depressed patients has been attributed to its ability to improve sleep quality. These properties underline the use of melatonin analogues as a promising alternative for the treatment of depression.

Agomelatine in the treatment of mood and anxiety disorders

The antidepressant agomelatine combines a novel mechanism of action with certain advantages over currently available antidepressants, in terms of restoration of sleep, absence of treatment-emergent sexual dysfunction, and fewer discontinuation symptoms. What is its potential role in clinical practice?

Good night and good luck: norepinephrine in sleep pharmacology

Sleep is a crucial biological process that is regulated through complex interactions between multiple brain regions and neuromodulators. As sleep disorders can have deleterious impacts on health and quality of life, a wide variety of pharmacotherapies have been developed to treat conditions of excessive wakefulness and excessive sleepiness. The neurotransmitter norepinephrine (NE), through its involvement in the ascending arousal system, impacts the efficacy of many wake- and sleep-promoting medications. Wake-promoting drugs such as amphetamine and modafinil increase extracellular levels of NE, enhancing transmission along the wake-promoting pathway. GABAergic sleep-promoting medications like benzodiazepines and benzodiazepine-like drugs that act more specifically on benzodiazepine receptors increase the activity of GABA, which inhibits NE transmission and the wake-promoting pathway. Melatonin and related compounds increase sleep by suppressing the activity of the neurons in the brain's circadian clock, and NE influences the synthesis of melatonin. Antihistamines block the wake-promoting effects of histamine, which shares reciprocal signaling with NE. Many antidepressants that affect the signaling of NE are also used for treatment of insomnia. Finally, adrenergic receptor antagonists that are used to treat cardiovascular disorders have considerable sedative effects. Therefore, NE, long known for its role in maintaining general arousal, is also a crucial player in sleep pharmacology. The purpose of this review is to consider the role of NE in the actions of wake- and sleep-promoting drugs within the framework of the brain arousal systems.

Longitudinal association between depressive symptoms and disability burden among older persons

BACKGROUND

Although depressive symptoms in older persons are common, their association with disability burden is not well understood. The authors evaluated the association between level of depressive symptoms and severity of subsequent disability over time and determined whether this relationship differed by sex.

METHODS

Participants included 754 community-living persons aged 70 years or older who underwent monthly assessments of disability in four essential activities of daily living for up to 117 months. Disability was categorized each month as none, mild, and severe. Depressive symptoms, assessed every 18 months, were categorized as low (referent group), moderate, and high. Multinomial logit models invoking Generalized Estimating Equation were used to calculate odds ratios and 95% confidence intervals.

RESULTS

Moderate (odds ratio = 1.30; 95% confidence interval: 1.18-1.43) and high (odds ratio = 1.68; 95% confidence interval: 1.50-1.88) depressive symptoms were associated with mild disability, whereas only high depressive symptoms were associated with severe disability (odds ratio = 2.05; 95% confidence interval: 1.76-2.39). Depressive symptoms were associated with disability burden in both men and women, with modest differences by sex; men had an increased likelihood of experiencing severe disability at both moderate and high levels of depressive symptoms, whereas only high depressive symptoms were associated with severe disability in women.

CONCLUSIONS

Levels of depressive symptoms below the threshold for subsyndromal depression are associated with increased disability burden in older persons. Identifying and treating varying levels of depressive symptoms in older persons may ultimately help to reduce the burden of disability in this population.