Observed sleep/wakefulness and severity of dementia in an Alzheimer's disease special care unit

Orexin Receptor Antagonism: Normalizing Sleep Architecture in Old Age and Disease

Sleep is essential for human well-being, yet the quality and quantity of sleep reduce as age advances. Older persons (>65 years old) are more at risk of disorders accompanied and/or exacerbated by poor sleep. Furthermore, evidence supports a bidirectional relationship between disrupted sleep and Alzheimer's disease (AD) or related dementias. Orexin/hypocretin neuropeptides stabilize wakefulness, and several orexin receptor antagonists (ORAs) are approved for the treatment of insomnia in adults. Dysregulation of the orexin system occurs in aging and AD, positioning ORAs as advantageous for these populations. Indeed, several clinical studies indicate that ORAs are efficacious hypnotics in older persons and dementia patients and, as in adults, are generally well tolerated. ORAs are likely to be more effective when administered early in sleep/wake dysregulation to reestablish good sleep/wake-related behaviors and reduce the accumulation of dementia-associated proteinopathic substrates. Improving sleep in aging and dementia represents a tremendous opportunity to benefit patients, caregivers, and health systems.

24 h Rest/Activity Rhythms in Older Adults with Memory Impairment: Associations with Cognitive Performance and Depressive Symptomatology

Little is known about links of circadian rhythm alterations with neuropsychiatric symptoms and cognition in memory impaired older adults. Associations of actigraphic rest/activity rhythms (RAR) with depressive symptoms and cognition are examined using function-on-scalar regression (FOSR). Forty-four older adults with memory impairment (mean: 76.84 ± 8.15 years; 40.9% female) completed 6.37 ± 0.93 days of actigraphy, the Beck depression inventory-II (BDI-II), mini-mental state examination (MMSE) and consortium to establish a registry for Alzheimer's disease (CERAD) delayed word recall. FOSR models with BDI-II, MMSE, or CERAD as individual predictors adjusted for demographics (Models A1-A3) and all three predictors and demographics (Model B). In Model B, higher BDI-II scores are associated with greater activity from 12:00-11:50 a.m., 2:10-5:50 p.m., 8:40-9:40 p.m., 11:20-12:00 a.m., higher CERAD scores with greater activity from 9:20-10:00 p.m., and higher MMSE scores with greater activity from 5:50-10:50 a.m. and 12:40-5:00 p.m. Greater depressive symptomatology is associated with greater activity in midafternoon, evening, and overnight into midday; better delayed recall with greater late evening activity; and higher global cognitive performance with greater morning and afternoon activity (Model B). Time-of-day specific RAR alterations may affect mood and cognitive performance in this population.

Sleep Dysregulation Is Associated with 18F-FDG PET and Cerebrospinal Fluid Biomarkers in Alzheimer's Disease

Background

Sleep impairment has been commonly reported in Alzheimer's disease (AD) patients. The association between sleep dysregulation and AD biomarkers has been separately explored in mild cognitive impairment (MCI) and AD patients.

Objective

The present study investigated cerebrospinal-fluid (CSF) and 18F-fluoro-deoxy-glucose positron emission tomography (18F-FDG-PET) biomarkers in MCI and AD patients in order to explore their association with sleep parameters measured with polysomnography (PSG).

Methods

MCI and AD patients underwent PSG, 18F-FDG-PET, and CSF analysis for detecting and correlating these biomarkers with sleep architecture.

Results

Thirty-five patients were included in the study (9 MCI and 26 AD patients). 18F-FDG uptake in left Brodmann area 31 (owing to the posterior cingulate cortex) correlated negatively with REM sleep latency (p = 0.013) and positively with REM sleep (p = 0.033). 18F-FDG uptake in the hippocampus was negatively associated with sleep onset latency (p = 0.041). Higher CSF orexin levels were associated with higher sleep onset latency (p = 0.042), Non-REM stage 1 of sleep (p = 0.031), wake after sleep onset (p = 0.028), and lower sleep efficiency (p = 0.045). CSF levels of Aβ42 correlated negatively with the wake bouts index (p = 0.002). CSF total-tau and phosphorylated tau levels correlated positively with total sleep time (p = 0.045) and time in bed (p = 0.031), respectively.

Conclusion

Sleep impairment, namely sleep fragmentation, REM sleep dysregulation, and difficulty in initiating sleep correlates with AD biomarkers, suggesting an effect of sleep on the pathological processes in different AD stages. Targeting sleep for counteracting the AD pathological processes represents a timely need for clinicians and researchers.

Glymphatic System and Mitochondrial Dysfunction as Two Crucial Players in Pathophysiology of Neurodegenerative Disorders

Neurodegenerative diseases are a complex problem affecting millions of people around the world. The pathogenesis is not fully understood, but it is known that both insufficiency of the glymphatic system and mitochondrial disorders affect the development of pathology. It appears that these are not just two independent factors that coexist in the processes of neurodegeneration, but that they often interact and drive each other. Bioenergetics disturbances are potentially associated with the accumulation of protein aggregates and impaired glymphatic clearance. Furthermore, sleep disorders characteristic of neurodegeneration may impair the work of both the glymphatic system and the activity of mitochondria. Melatonin may be one of the elements linking sleep disorders with the function of these systems. Moreover, noteworthy in this context is the process of neuroinflammation inextricably linked to mitochondria and its impact not only on neurons, but also on glia cells involved in glymphatic clearance. This review only presents possible direct and indirect connections between the glymphatic system and mitochondria in the process of neurodegeneration. Clarifying the connection between these two areas in relation to neurodegeneration could lead to the development of new multidirectional therapies, which, due to the complexity of pathogenesis, seems to be worth considering.

Burden of Insomnia and Sleep Disturbances and the Impact of Sleep Treatments in Patients with Probable or Possible Alzheimer's Disease: A Structured Literature Review

Background:

Sleep disturbances are frequent in Alzheimer’s disease (AD).

Objective:

To summarize the impact of sleep disturbances on AD patients and their caregivers and the effects of currently available sleep therapies.

Methods:

Published studies (January 1985–March 2020) assessing the burden associated with insomnia/sleep disturbances in the AD population and insomnia treatment effects were identified by searching PubMed, Embase, and Cochrane Library and screened against inclusion criteria.

Results:

58 studies assessing patient and caregiver burden, institutionalization, and insomnia treatments in AD patients with sleep disturbances were identified. Sleep disturbances were associated with worse cognition, functional ability, and behavioral and neuropsychological functioning. Health status and quality of life of both patients and caregivers were reduced in the presence of sleep disturbances. Sleep disturbances were also associated with institutionalization. Although significant associations between sleep problems and clinical outcomes were apparent, there was generally no control for other influencing factors (e.g., cognitive status). Bright light and behavioral therapies as well as drugs showed some promise in AD patients, but studies were primarily small and limited data were available, particularly in regard to the effect on associated clinical burden.

Conclusion:

Sleep disturbances are a significant problem for AD patients and caregivers, associated with behavioral and psychological problems and cognitive decline. However, they remain poorly characterized and under-researched. As the global population is aging and AD is on thes rise, data from larger, prospective trials are required to fully understand the clinical correlates of sleep disturbances and the impact insomnia treatments can have.

Sleep deficiency as a driver of cellular stress and damage in neurological disorders

Neurological disorders encompass an extremely broad range of conditions, including those that present early in development and those that progress slowly or manifest with advanced age. Although these disorders have distinct underlying etiologies, the activation of shared pathways, e.g., integrated stress response (ISR) and the development of shared phenotypes (sleep deficits) may offer clues toward understanding some of the mechanistic underpinnings of neurologic dysfunction. While it is incontrovertibly complex, the relationship between sleep and persistent stress in the brain has broad implications in understanding neurological disorders from development to degeneration. The convergent nature of the ISR could be a common thread linking genetically distinct neurological disorders through the dysregulation of a core cellular homeostasis pathway.

The efficacy and safety of zolpidem and zopiclone to treat insomnia in Alzheimer's disease: a randomized, triple-blind, placebo-controlled trial

No prior studies have evaluated the efficacy and safety of zolpidem and zopiclone to treat insomnia of demented patients. This randomized, triple-blind, placebo-controlled clinical trial used these drugs to treat patients with probable, late onset Alzheimer's dementia (AD) (DSM V and NINCDS-ADRDA criteria) exhibiting insomnia (DSM V criteria and nocturnal NPI scores ≥ 2). Actigraphic records were performed for 7 days at baseline and for 14 days during the treatment period in 62 patients aged 80.5 years in average and randomized at a 1:1:1 ratio for administration of zolpidem 10 mg/day, zopiclone 7.5 mg/day or placebo. Primary endpoint was the main nocturnal sleep duration (MNSD), whereas secondary outcomes were the proportion of the night time slept, awake time after sleep onset (WASO), nocturnal awakenings, total daytime sleep time and daytime naps. Cognitive and functional domains were tested before and after drug/placebo use. Three participants under zopiclone use had intervention interrupted due to intense daytime sedation and worsened agitation with wandering. Zopiclone produced an 81 min increase in MNSD (95% confidence interval (CI): -0.8, 163.2), a 26 min reduction in WASO (95% CI: -56.2, 4.8) and a 2-episode decrease in awakening per night (95% CI: -4.0, 0.4) in average compared to placebo. Zolpidem yielded no significant difference in MNSD despite a significant 22 min reduction in WASO (95% CI: -52.5, 8.3) and a reduction of 1 awakening each night (95% CI: -3.4, 1.2) in relation to placebo. There was a 1-point reduction in mean performance in the symbols search test among zolpidem users (95% CI: -4.1, 1.5) and an almost eight-point reduction in average scores in the digit-symbol coding test among zopiclone users (95% CI: -21.7, 6.2). In summary, short-term use of zolpidem or zopiclone by older insomniacs with AD appears to be clinically helpful, even though safety and tolerance remain issues to be personalized in healthcare settings and further investigated in subsequent trials. This trial was registered in ClinicalTrials.gov Identifier: NCT03075241.

Impact of Pharmacotherapy on Insomnia in Patients with Alzheimer's Disease

Insomnia is a pervasive sleep disorder affecting numerous patients across diverse demographical populations and comorbid disease states. Contributing factors are often a complex interaction of biological, psychological, and social components, requiring a multifaceted approach in terms of both diagnosis and management. In the setting of Alzheimer’s disease, insomnia is an even more complicated issue, with a higher overall prevalence than in the general population, greater complexity of contributing etiologies, and differences in diagnosis (at times based on caregiver observation of sleep disruption rather than subjective complaints by the individual with the disorder), and requiring more discretion in terms of treatment, particularly in regard to adverse effect profile concerns. There also is growing evidence of the bidirectional nature of sleep disruption and Alzheimer’s disease, with insomnia potentially contributing to disease progression, making the condition even more paramount to address. The objective of this review was to provide the clinician with an overview of treatment strategies that may have value in the treatment of disturbed sleep in Alzheimer’s disease. Nonpharmacological approaches to treatment should be exhausted foremost; however, pharmacotherapy may be needed in certain clinical scenarios, which can be a challenge for clinicians given the paucity of evidence and guidelines for treatment in the subpopulation of Alzheimer’s disease. Agents such as sedating antidepressants, melatonin, and site-specific γ-aminobutyric acid agonists are often employed based on historical usage but are not necessarily supported by high-quality trials. Newer agents such as dual orexin receptor antagonists have demonstrated some promise but still need further evaluation.

Connecting Mind-Body Therapy-Mediated Effects to Pathological Features of Alzheimer's Disease

Alzheimer's disease (AD) is a complex, multifactorial neurodegenerative disorder that represents a major and increasing global health challenge. In most cases, the first clinical symptoms of AD are preceded by neuropathological changes in the brain that develop years to decades before their onset. Therefore, research in the last years has focused on this preclinical stage of AD trying to discover intervention strategies that might, if implemented effectively, delay or prevent disease progression. Among those strategies, mind-body therapies such as yoga and meditation have gained increasing interest as complementary alternative interventions. Several studies have reported a positive impact of yoga and meditation on brain health in both healthy older adults and dementia patients. However, the underlying neurobiological mechanisms contributing to these effects are currently not known in detail. More specifically, it is not known whether yogic interventions, directly or indirectly, can modulate risk factors or pathological mechanisms involved in the development of dementia. In this article, we first review the literature on the effects of yogic practices on outcomes such as cognitive functioning and neuropsychiatric symptoms in patients with mild cognitive impairment and dementia. Then, we analyze how yogic interventions affect different risk factors as well as aspects of AD pathophysiology based on observations of studies in healthy individuals or subjects with other conditions than dementia. Finally, we integrate this evidence and propose possible mechanisms that might explain the positive effects of yogic interventions in cognitively impaired individuals.

Long-Term, All-Day Exposure to Circadian-Effective Light Improves Sleep, Mood, and Behavior in Persons with Dementia

BACKGROUND

Persons with Alzheimer's disease and related dementias (ADRD) frequently experience sleep-wake (circadian) cycle disturbances that lead them to remain awake at night, causing stress and fatigue for families and caregivers. Light therapy shows promise as a nonpharmacological treatment for regulating sleep in this population.

OBJECTIVE

We investigated the long-term impact of a circadian-effective lighting intervention on sleep, mood, and behavior problems in persons with ADRD.

METHODS

This 25-week clinical trial administered an all-day lighting intervention to 47 patients with ADRD in 9 senior-care facilities, employing wrist-worn actigraphy measures and standardized measures of sleep quality, mood, and behavior.

RESULTS

The intervention significantly improved Pittsburgh Sleep Quality Index scores, from an estimated mean±SEM of 11.89±0.53 at baseline to 5.36±0.63 at the end of the intervention. Additional improvements were noted for sleep efficiency data from actigraph measurements. The intervention significantly reduced Cornell Scale for Depression in Dementia scores (mean±SEM of 11.36±0.74 at baseline and 4.18±0.88 at the end of the intervention) and Cohen-Mansfield Agitation Inventory scores (mean±SEM of 47.10±1.98 at baseline and 35.33±2.23 at the end of the intervention).

CONCLUSION

A regular circadian-effective daytime lighting intervention can improve sleep at night and reduce depression and agitation in patients with dementia living in controlled environments. More importantly, the positive effects of the tailored lighting intervention on these outcomes appear to be cumulative over time.

Slow Wave Sleep Is a Promising Intervention Target for Alzheimer's Disease

Alzheimer's disease (AD) is the major cause of dementia, characterized by the presence of amyloid-beta plaques and neurofibrillary tau tangles. Plaques and tangles are associated with sleep-wake cycle disruptions, including the disruptions in non-rapid eye movement (NREM) slow wave sleep (SWS). Alzheimer's patients spend less time in NREM sleep and exhibit decreased slow wave activity (SWA). Consistent with the critical role of SWS in memory consolidation, reduced SWA is associated with impaired memory consolidation in AD patients. The aberrant SWA can be modeled in transgenic mouse models of amyloidosis and tauopathy. Animal models exhibited slow wave impairments early in the disease progression, prior to the deposition of amyloid-beta plaques, however, in the presence of abundant oligomeric amyloid-beta. Optogenetic rescue of SWA successfully halted the amyloid accumulation and restored intraneuronal calcium levels in mice. On the other hand, optogenetic acceleration of slow wave frequency exacerbated amyloid deposition and disrupted neuronal calcium homeostasis. In this review, we summarize the evidence and the mechanisms underlying the existence of a positive feedback loop between amyloid/tau pathology and SWA disruptions that lead to further accumulations of amyloid and tau in AD. Moreover, since SWA disruptions occur prior to the plaque deposition, SWA disruptions may provide an early biomarker for AD. Finally, we propose that therapeutic targeting of SWA in AD might lead to an effective treatment for Alzheimer's patients.

Sleep Disturbances in MCI and AD: Neuroinflammation as a Possible Mediating Pathway

Mild cognitive impairment (MCI) and Alzheimer's disease (AD) affect a high proportion of the elderly population with an increasing prevalence. Sleep disturbances are frequent in those with MCI and AD. This review summarizes existing research on sleep disturbances and neuroinflammation in MCI and AD. Although strong evidence supports various pathways linking sleep and AD pathology, the temporal direction of this central relationship is not yet known. Improved understanding of sleep disturbance and neuroinflammation in MCI and AD may aid in the identification of targets for their prevention.

Therapeutic implications of circadian clocks in neurodegenerative diseases

Circadian clocks, endogenous oscillators generating daily biological rhythms, have important roles in the nervous system to control diverse cellular processes-not only in the suprachiasmatic nucleus (SCN), where the master clocks reside to synchronize all circadian clocks in the body but also in other non-SCN areas. Accumulating evidence has shown relationships between circadian abnormalities (e.g., sleep disturbances and abnormal rest-activity rhythms) and disease progressions in various neurodegenerative diseases, including Alzheimer's (AD) and Parkinson's (PD) disease. Although circadian abnormalities were frequently considered as consequences of disease onsets, recent studies suggest altered circadian clocks as risk factors to develop neurodegenerative diseases via altered production or clearance rates of toxic metabolites like amyloid β. In this review, we will summarize circadian clock-related pathologies in the most common neurodegenerative diseases in the central nervous system, AD and PD. Then, we will introduce the current clinical trials to rescue circadian abnormalities in AD and PD patients. Finally, a discussion about how to improve targeting circadian clocks to increase treatment efficiencies and specificities will be followed. This discussion will provide insight into circadian clocks as potential therapeutic targets to attenuate onsets and progressions of neurodegenerative diseases.

Cognitive Function, Consent for Participation, and Compliance With Wearable Device Protocols in Older Adults

Background

Population-based studies of older adults increasingly use wearable devices to measure activity and sleep. Whether cognitive impairment reduces consent and compliance has not been assessed.

Methods

In the context of a nationally representative cohort of community-dwelling adults aged 62-90, individuals were invited to participate in a sleep and activity substudy that required wearing a wrist actigraph for 72 consecutive hours. Cognitive function in the parent study was assessed with the survey adaptation of the Montreal Cognitive Assessment, and individuals were categorized as normal, mild cognitive impairment, or dementia. Participants were asked to press an event marker on the actigraph when they started trying to fall asleep and when they awoke each day. Logistic and negative binomial regressions were used to link cognitive status to nonconsent, returning usable data, wearing the actigraph three full days, ever taking the device off-wrist during the 3-day study period, and pushing the event markers, controlling for demographics.

Results

Cognitive status was not associated with nonconsent, returning usable data, off-wrist, or missing days. However, individuals classified with dementia were more likely to miss bedtime and wake-up event markers. Individuals classified as mild cognitive impairment were more likely to miss wake-up event markers.

Conclusions

Impaired cognition does not seem to be a barrier to compliance with simply wearing a device but may affect compliance with additional action such as pressing event markers.

Alzheimer's disease: Neurotransmitters of the sleep-wake cycle

With aging, our sleeping pattern alters. Elderly often wake unrested because their sleep time and sleep efficacy is reduced. In Alzheimer's disease (AD) patients, these alterations are even more pronounced and may further aggravate cognitive decline. Therefore, sleep disturbances greatly impact self-care ability, caregiver exhaustion and institutionalization rate. Reestablishing an effective sleep-wake cycle in these patients still remains an unresolved challenge, partly because sleep physiology is quite complex and multiple neurotransmitter systems contribute to a single process. Gaining a better understanding of sleep physiology will be crucial for further research. Conjointly, animal models, along with a multidisciplinary approach, will be of great value to establish a common ground between AD and sleep disturbances and work towards a potential therapeutic application.

Sleep architecture changes in the APP23 mouse model manifest at onset of cognitive deficits

Alzheimer's disease (AD), which accounts for most of the dementia cases, is, aside from cognitive deterioration, often characterized by the presence of non-cognitive symptoms such as activity and sleep disturbances. AD patients typically experience increased sleep fragmentation, excessive daytime sleepiness and night-time insomnia. Here, we sought to investigate the link between sleep architecture, cognition and amyloid pathology in the APP23 amyloidosis mouse model for AD. By means of polysomnographic recordings the sleep-wake cycle of freely-moving APP23 and wild-type (WT) littermates of 3, 6 and 12 months of age was examined. In addition, ambulatory cage activity was assessed by interruption of infrared beams surrounding the home cage. To assess visuo-spatial learning and memory a hidden-platform Morris-type Water Maze (MWM) experiment was performed. We found that sleep architecture is only slightly altered at early stages of pathology, but significantly deteriorates from 12 months of age, when amyloid plaques become diffusely present. APP23 mice of 12 months old had quantitative reductions of NREM and REM sleep and were more awake during the dark phase compared to WT littermates. These findings were confirmed by increased ambulatory cage activity during that phase of the light-dark cycle. No quantitative differences in sleep parameters were observed during the light phase. However, during this light phase, the sleep pattern of APP23 mice was more fragmented from 6 months of age, the point at which also cognitive abilities started to be affected in the MWM. Sleep time also positively correlated with MWM performance. We also found that spectral components in the EEG started to alter at the age of 6 months. To conclude, our results indicate that sleep architectural changes arise around the time the first amyloid plaques start to form and cognitive deterioration becomes apparent. These changes start subtle, but gradually worsen with age, adequately mimicking the clinical condition.

Melatonin in Synaptic Impairments of Alzheimer's Disease

Alzheimer's disease (AD) underlies dementia for millions of people worldwide with no effective treatment. The dementia of AD is thought stem from the impairments of the synapses because of their critical roles in cognition. Melatonin is a neurohormone mainly released by the pineal gland in a circadian manner and it regulates brain functions in various manners. It is reported that both the melatonin deficit and synaptic impairments are present in the very early stage of AD and strongly contribute to the progress of AD. In the mammalian brains, the effects of melatonin are mainly relayed by two of its receptors, melatonin receptor type 1a (MT1) and 1b (MT2). To have a clear idea on the roles of melatonin in synaptic impairments of AD, this review discussed the actions of melatonin and its receptors in the stabilization of synapses, modulation of long-term potentiation, as well as their contributions in the transmissions of glutamatergic, GABAergic and dopaminergic synapses, which are the three main types of synapses relevant to the synaptic strength. The synaptic protective roles of melatonin in AD treatment were also summarized. Regarding its protective roles against amyloid-β neurotoxicity, tau hyperphosphorylation, oxygenation, inflammation as well as synaptic dysfunctions, melatonin may be an ideal therapeutic agent against AD at early stage.

Sleep Disorders Associated With Alzheimer's Disease: A Perspective

Sleep disturbances, as well as sleep-wake rhythm disturbances, are typical symptoms of Alzheimer's disease (AD) that may precede the other clinical signs of this neurodegenerative disease. Here, we describe clinical features of sleep disorders in AD and the relation between sleep disorders and both cognitive impairment and poor prognosis of the disease. There are difficulties of the diagnosis of sleep disorders based on sleep questionnaires, polysomnography or actigraphy in the AD patients. Typical disturbances of the neurophysiological sleep architecture in the course of the AD include deep sleep and paradoxical sleep deprivation. Among sleep disorders occurring in patients with AD, the most frequent disorders are sleep breathing disorders and restless legs syndrome. Sleep disorders may influence circadian fluctuations of the concentrations of amyloid-β in the interstitial brain fluid and in the cerebrovascular fluid related to the glymphatic brain system and production of the amyloid-β. There is accumulating evidence suggesting that disordered sleep contributes to cognitive decline and the development of AD pathology. In this mini-review, we highlight and discuss the association between sleep disorders and AD.

Can Better Management of Periodontal Disease Delay the Onset and Progression of Alzheimer's Disease?

A risk factor relationship exists between periodontal disease and Alzheimer's disease (AD) via tooth loss, and improved memory following dental intervention. This links the microbial contribution from indigenous oral periodontal pathogens to the manifestation of chronic conditions, such as AD. Here, we use Porphyromonas gingivalis infection to illustrate its effect on mental health. P. gingivalis infection, in its primary sub-gingival niche, can cause polymicrobial synergy and dysbiosis. Dysbiosis describes the residency of select commensals from the oral cavity following co-aggregation around the dominant keystone pathogen, such as P. gingivalis, to gain greater virulence. The initial process involves P. gingivalis disturbing neutrophil mediated innate immune responses in the healthy gingivae and then downregulating adaptive immune cell differentiation and development to invade, and subsequently, establish new dysbiotic bacterial communities. Immune responses affect the host in general and functionally via dietary adjustments caused by tooth loss. Studies from animals orally infected with P. gingivalis confirm this bacterium can transmigrate to distant organ sites (the brain) and contribute toward peripheral and intracerebral inflammation, and compromise vascular and microvascular integrity. In another study, P. gingivalis infection caused sleep pattern disturbances by altering glial cell light/dark molecular clock activity, and this, in turn, can affect the clearance of danger associated molecular patterns, such as amyloid-β, via the glymphatic system. Since P. gingivalis can transmigrate to the brain and modulate organ-specific inflammatory innate and adaptive immune responses, this paper explores whether better management of indigenous periodontal bacteria could delay/prevent the onset and/or progression of dementia.

Sleep and Alzheimer's disease: A pivotal role for the suprachiasmatic nucleus

Alzheimer's disease (AD), which accounts for most of the dementia cases, is, aside from cognitive deterioration, often characterized by the presence of non-cognitive symptoms. Society is desperately in need for interventions that alleviate the economic and social burden related to AD. Circadian dysrhythmia, one of these symptoms in particular, immensely decreases the self-care ability of AD patients and is one of the main reasons of caregiver exhaustion. Studies suggest that these circadian disturbances form the root of sleep-wake problems, diagnosed in more than half of AD patients. Sleep abnormalities have generally been considered merely a consequence of AD pathology. Recent evidence suggests that a bidirectional relationship exists between sleep and AD, and that poor sleep might negatively impact amyloid burden, as well as cognition. The suprachiasmatic nucleus (SCN), the main circadian pacemaker, is subjected to several alterations during the course of the disease. Its functional deterioration might fulfill a crucial role in the relation between AD pathophysiology and the development of sleep abnormalities. This review aims to give a concise overview of the anatomy and physiology of the SCN, address how AD pathology precisely impacts the SCN and to what degree these alterations can contribute to the progression of the disease.

Sleep in older adults and in subjects with dementia

The neuronal structures for the regulation of sleep and wakefulness are located in the brain. This complex network is vulnerable to numerous factors, most importantly neurodegenerative diseases and drugs. The macrostructure and microstructure of sleep change with age. These changes are more pronounced in subjects with dementia. Sleep disorders in subjects with dementia may be independent of dementia or caused by dementia. Furthermore, epidemiological studies reveal that sleep disorders per se may induce dementia by reduction of cerebral clearance of beta-amyloids. The population attributable risk (PAR) of sleep disturbances to the incidence of dementia is estimated to be about 15%; therefore, management of sleep disturbances in older adults and subjects with dementia gives the opportunity of an impact on incidence and course of dementia. Sleep history should be taken from each individual and obvious sleep disturbances, especially sleep apnea, should be managed according to current guidelines. Future studies that concern the incidence and the management of dementia must take into account sleep and sleep disturbances.

Sleep disturbances are key symptoms of very early stage Alzheimer disease with behavioral and psychological symptoms: a Japan multi-center cross-sectional study (J-BIRD)

BACKGROUND

Sleep disturbances in Alzheimer disease (AD) may affect behavioral and psychological symptoms of dementia (BPSD). Our aim was to elucidate the associations between sleep disturbances and other BPSD at different stages of AD.

METHODS

This investigation was part of a multicenter-retrospective study in Japan (J-BIRD). Eligible for final analyses were 684 AD patients. Global severity of dementia was estimated using the Clinical Dementia Rating (CDR) scale. BPSD were assessed using the Neuropsychiatric Inventory (NPI). We analyzed the relationships between sleep disturbances and BPSD at different stages of AD according to the CDR score.

RESULTS

Among the 684 AD patients, 146 (21.3%) had sleep disturbances. Patients with very early AD (CDR 0.5) and sleep disturbances had significantly more BPSD than those without sleep disturbances, as indicated by the higher prevalence of the following four NPI items: anxiety, euphoria, disinhibition, and aberrant motor behavior. In AD at CDR 2, (moderate AD) only one NPI item (irritability) was affected, while none was affected at CDR 1 (mild AD) and 3 (severe AD). Multiple regression analyses were performed in those with AD having various CDR scores. At CDR 0.5, the presence of sleep disturbances was associated with a high total NPI score (β = 0.32, p < 0.001). However, other factors, including cognitive decline, age, gender, and years of education, were not significantly associated with the NPI score. At CDR 1 and 2, no factor was significantly related to BPSD.

CONCLUSION

Sleep disturbances were strongly associated with other BPSD in the very early stage of AD. Copyright © 2016 John Wiley & Sons, Ltd.

Sleep Patterns and Neuropsychiatric Symptoms in Hospitalized Patients With Dementia

The authors examined 28 dementia inpatients receiving treatment as usual. Beginning-to-end differences in neuropsychiatric symptoms and actigraphic sleep patterns were measured. Using a mixed-model, the authors regressed neuropsychiatric symptoms on average sleep minutes (between-subjects effect) and each night's deviation from average (within-subject effect). Sleep did not significantly differ from beginning to end of participation, whereas neuropsychiatric symptoms did. Average sleep minutes predicted average neuropsychiatric symptoms (p=0.002), but each night's deviation from the average did not predict next day's symptoms (p=0.90). These findings raise questions about the immediate benefits of treating sleep-wake disturbances on neuropsychiatric symptoms in hospitalized inpatients with dementias.

Staffing and the mealtime experience of nursing home residents on a Special Care Unit

As part of a study that examined the social, cultural, clinical, and environmental factors that influence eating behavior in nursing homes, the effect of staffing on the mealtime experience of residents in a Special Care Unit (SCU) for dementia patients was investigated. An adequate staff to resident ratio, the presence of a knowledgeable and skillful nursing assistant who was an excellent role model, and sufficient supervision positively affected the experience of residents, making lunchtime a pleasant and nourishing event. In the evening, however; overtaxed and poorly supervised aides resorted to strategies that made dinnertime a hurried, unpleasant experience and put residents under duress. A discussion of how to provide extra help at mealtime, improve the education and training of staff, and enhance supervision at mealtime is presented.

Outcomes of nighttime physical restraint removal for severely impaired nursing home residents

There is ample evidence that physical restraint reduction does not lead to increased falls or injuries. This study tests the effect of removing nighttime restraints by comparing two groups: Restrained in bed at pre- but not postintervention (n = 51), or restrained in bed at both pre- and post-intervention (n = 11). No differences in nighttime fall rates between the two groups were detected.

Nighttime physical restraint removal does not lead to increases in falls from bed in older nursing home residents. Although markedly reduced in nursing homes, restraint use remains a common practice among hospitalized older adults. We should continue to focus efforts on developing new, individualized approaches to reduce risk of falling from bed among frail elders.

“Friendship” Interactions and Expression of Agitation among Residents of a Dementia Care Unit

“Friendships” (ongoing interpersonal interactions) and agitated behavior were studied among 59 residents of a dementia special care unit; most residents had mild to moderate cognitive impairment. Behavior scan data were recorded by trained observers over six months. Three scans per hour were conducted, seven days a week, between 9 a.m. and 9 p.m., producing more than 17,000 observations. A marginal model for binary longitudinal data was developed to associate covariates with repeated observations of agitation, the dependent variable; generalized estimating equations were used to estimate regression parameters. Friendship behavior was significantly associated with (less) observed agitation in this group of dementia residents, controlling for additional variables expected to predict agitation. Opportunity for self-initiated interpersonal engagement may contribute significantly to the well-being of moderately impaired dementia residents. Repeated over-time assessments are important in understanding factors related to expression of problem behaviors in this population.

"Sundowning" as a biological phenomenon: current understandings and future directions: an update

The clinical phenomenon of early evening disruptive behavior also called "Sundowning" in elderly patients has been largely reported in the medical literature without a consistent diagnosis and criteria to define this phenomenon. The current understandings of sundowning are incomplete and current treatment strategies have relied heavily on use of antipsychotic medications, despite side effects and limited evidence to justify their use. A comprehensive understanding of the biogenesis of this phenomenon and mechanistic changes from oxidative pathways may provide novel information on completing the sundowning puzzle. Future studies could examine the utility of natural factors in reviving neuronal energy loss and altering the oxidative pathways might be safe and additional options in development of treatment models for this behavioral disorder.

Tailored Lighting Intervention for Persons with Dementia and Caregivers Living at Home

OBJECTIVES

Light therapy has shown promise as a nonpharmacological treatment to help regulate abnormal sleep-wake patterns and associated behavioral issues prevalent among individuals diagnosed with Alzheimer's disease and related dementia (ADRD). The present study investigated the effectiveness of a lighting intervention designed to increase circadian stimulation during the day using light sources that have high short-wavelength content and high light output.

METHODS

Thirty-five persons with ADRD and 34 caregivers completed the 11-week study. During week 1, subjective questionnaires were administered to the study participants. During week 2, baseline data were collected using Daysimeters and actigraphs. Researchers installed the lighting during week 3, followed by 4 weeks of the tailored lighting intervention. During the last week of the lighting intervention, Daysimeter, actigraph and questionnaire data were again collected. Three weeks after the lighting intervention was removed, a third data collection (post-intervention assessment) was performed.

RESULTS

The lighting intervention significantly increased circadian entrainment, as measured by phasor magnitude and sleep efficiency, as measured by actigraphy data, and significantly reduced symptoms of depression in the participants with ADRD. The caregivers also exhibited an increase in circadian entrainment during the lighting intervention; a seasonal effect of greater sleep efficiency and longer sleep duration was also found for caregivers.

CONCLUSIONS

An ambient lighting intervention designed to increase daytime circadian stimulation can be used to increase sleep efficiency in persons with ADRD and their caregivers, and may also be effective for other populations such as healthy older adults with sleep problems, adolescents, and veterans with traumatic brain injury.

Effect of home-based light treatment on persons with dementia and their caregivers

Sleep disorders are problematic for persons with dementia and their family caregivers. This randomized controlled trial with crossover evaluated the effects of an innovative blue-white light therapy on 17 pairs of home-dwelling persons with dementia and their caregivers. Subjects with dementia received blue-white light and control ('red-yellow' light) for six weeks separated by a four-week washout. Neither actigraphic nor most self-reported sleep measures significantly differed for subjects with dementia. For caregivers, both sleep and role strain improved. No evidence of retinal light toxicity was observed. Six weeks of modest doses of blue-white light appear to improve sleep in caregivers but not in persons with dementia. Greater or prolonged circadian stimulation may be needed to determine if light is an effective treatment for persons with dementia.

The management of sleep and circadian disturbance in patients with dementia

Sleep and circadian disturbances are common among patients with dementia. Symptomatic manifestations vary according to dementia subtype, with one commonly shared pattern--the irregular sleep-wake rhythm (ISWR), a circadian disorder characterized by an absence of the sleepwake cycle’s circadian synchronization. Hypothesized mechanisms of circadian rhythm disturbance include suprachiasmatic nucleus (SCN) circadian pacemaker damage, pineal gland and melatonin secretion alterations, and reduced zeitbeigers and decreased input to the SCN. Management options include prescribed sleep/wake scheduling, light therapy, melatonin, physical and social activity, and mixed modality. The mixed-modality approach is the most effective method in treating ISWR. Pharmacologic interventions are controversial, with no evidence supporting their effectiveness while associated with multiple side effects. They should be used with caution and only be considered as short-term therapy. All treatment strategies should be individualized to achieve the best outcomes.

Sleep disturbance in dementia with Lewy bodies and Alzheimer's disease: a multicenter analysis

BACKGROUND/AIMS

Evidence suggests that patients with dementia with Lewy bodies (DLB) may have more nocturnal sleep disturbance than patients with Alzheimer's disease (AD). We sought to confirm such observations using a large, prospectively collected, standardized, multicenter-derived database, i.e. the National Alzheimer's Coordinating Center Uniform Data Set.

METHODS

Nocturnal sleep disturbance (NSD) data, as characterized by the Neuropsychiatric Inventory Questionnaire (NPI-Q), were derived from 4,531 patients collected between September 2005 and November 2008 from 32 National Institute on Aging participating AD centers. Patient and informant characteristics were compared between those with and without NSD by dementia diagnosis (DLB and probable AD). Finally, a logistic regression model was created to quantify the association between NSD status and diagnosis while adjusting for these patient/informant characteristics, as well as center.

RESULTS

NSD was more frequent in clinically diagnosed DLB relative to clinically diagnosed AD (odds ratio = 2.93, 95% confidence interval = 2.22-3.86). These results were independent from the gender of the patient or informant, whether the informant lived with the patient, and other patient characteristics, such as dementia severity, depressive symptoms, and NPI-Q-derived measures of hallucinations, delusions, agitation and apathy. In AD, but not DLB, patients, NSD was associated with more advanced disease. Comorbidity of NSD with hallucinations, agitation and apathy was higher in DLB than in AD. There was also evidence that the percentage of DLB cases with NSD showed wide variation across centers.

CONCLUSION

As defined by the NPI-Q, endorsement of the nocturnal behavior item by informants is more likely in patients with DLB when compared to AD, even after the adjustment of key patient/informant characteristics.

Tone-induced sleep fragmentation in persons with Alzheimer's disease: a feasibility study

Sleep fragmentation increases as Alzheimer's disease (AD) progresses. Its effects on cognition, specifically vigilant attention, are profoundly important because vigilant attention is thought to be the first step in memory acquisition. To our knowledge, no one has experimentally studied the effect of sleep fragmentation on vigilant attention in persons with AD. Therefore, this study piloted an experimental method using sound (tones produced by an audiometer) to induce sleep fragmentation. Participants enrolled in the University of Arkansas for Medical Sciences Memory Research Center ([MRC] n = 4) underwent one night of undisturbed and one of fragmented sleep. All participants tolerated the earphone needed for the tone-induced sleep fragmentation (TISF) method, and we were able to score awakenings in real time. However, only 50% of tones produced awakenings. The findings suggest that this experimental method is feasible for use in persons with mild AD. Based on the results, we will increase the duration, intensity, and frequency of tones delivered for optimal result.

Dorsomedial SCN neuronal subpopulations subserve different functions in human dementia

The suprachiasmatic nuclei (SCN) are necessary and sufficient for the maintenance of circadian rhythms in primate and other mammalian species. The human dorsomedial SCN contains populations of non-species-specific vasopressin and species-specific neurotensin neurons. We made time-series recordings of core body temperature and locomotor activity in 19 elderly, male, end-stage dementia patients and 8 normal elderly controls. Following the death of the dementia patients, neuropathological diagnostic information and tissue samples from the hypothalamus were obtained. Hypothalamic tissue was also obtained from eight normal control cases that had not had activity or core temperature recordings previously. Core temperature was analysed for parametric, circadian features, and activity was analysed for non-parametric and parametric circadian features. These indices were then correlated with the degree of degeneration seen in the SCN (glia/neuron ratio) and neuronal counts from the dorsomedial SCN (vasopressin, neurotensin). Specific loss of SCN neurotensin neurons was associated with loss of activity and temperature amplitude without increase in activity fragmentation. Loss of SCN vasopressin neurons was associated with increased activity fragmentation but not loss of amplitude. Evidence for a circadian rhythm of vasopressinergic activity was seen in the dementia cases but no evidence was seen for a circadian rhythm in neurotensinergic activity. These results provide evidence that the SCN is necessary for the maintenance of the circadian rhythm in humans, information on the role of neuronal subpopulations in subserving this function and the utility of dementia in elaborating brain-behaviour relationships in the human.

Circadian rhythm sleep disorders: part II, advanced sleep phase disorder, delayed sleep phase disorder, free-running disorder, and irregular sleep-wake rhythm. An American Academy of Sleep Medicine review

OBJECTIVE

This the second of two articles reviewing the scientific literature on the evaluation and treatment of circadian rhythm sleep disorders (CRSDs), employing the methodology of evidence-based medicine. We herein report on the accumulated evidence regarding the evaluation and treatment of Advamced Sleep Phase Disorder (ASPD), Delayed Sleep Phase Disorder (DSPD), Free-Running Disorder (FRD) and Irregular Sleep-Wake Rhythm ISWR).

METHODS

A set of specific questions relevant to clinical practice were formulated, a systematic literature search was performed, and relevant articles were abstracted and graded.

RESULTS

A substantial body of literature has accumulated that provides a rational basis the evaluation and treatment of CRSDs. Physiological assessment has involved determination of circadian phase using core body temperature and the timing of melatonin secretion. Behavioral assessment has involved sleep logs, actigraphy and the Morningness-Eveningness Questionnaire (MEQ). Treatment interventions fall into three broad categories: 1) prescribed sleep scheduling, 2) circadian phase shifting ("resetting the clock"), and 3) symptomatic treatment using hypnotic and stimulant medications.

CONCLUSION

Circadian rhythm science has also pointed the way to rational interventions for CRSDs and these treatments have been introduced into the practice of sleep medicine with varying degrees of success. More translational research is needed using subjects who meet current diagnostic criteria.

Disturbance and strategies for reactivation of the circadian rhythm system in aging and Alzheimer's disease

Circadian rhythm disturbances, such as sleep disorders, are frequently seen in aging and are even more pronounced in Alzheimer's disease (AD). Alterations in the biological clock, the suprachiasmatic nucleus (SCN), and the pineal gland during aging and AD are considered to be the biological basis for these circadian rhythm disturbances. Recently, our group found that pineal melatonin secretion and pineal clock gene oscillation were disrupted in AD patients, and surprisingly even in non-demented controls with the earliest signs of AD neuropathology (neuropathological Braak stages I-II), in contrast to non-demented controls without AD neuropathology. Furthermore, a functional disruption of the SCN was observed from the earliest AD stages onwards, as shown by decreased vasopressin mRNA, a clock-controlled major output of the SCN. The observed functional disconnection between the SCN and the pineal from the earliest AD stage onwards seems to account for the pineal clock gene and melatonin changes and underlies circadian rhythm disturbances in AD. This paper further discusses potential therapeutic strategies for reactivation of the circadian timing system, including melatonin and bright light therapy. As the presence of melatonin MT1 receptor in the SCN is extremely decreased in late AD patients, supplementary melatonin in the late AD stages may not lead to clear effects on circadian rhythm disorders.

Sleep and cognition in people with Alzheimer's disease

It is important that we identify factors that could lead to interventions to slow cognitive decline in people with Alzheimer's disease. One potentially modifiable factor in Alzheimer's disease is disturbed sleep. The effect of disturbed sleep on cognition is of profound importance in people with Alzheimer's disease because disturbed sleep may worsen memory complaints. Therefore, the purpose of this article is to provide an updated review of literature that describes the impact of disturbed sleep on cognition in healthy populations and discuss the implications that this relationship has for people with Alzheimer's disease and their formal and informal caregivers.

Effect of timed bright light treatment for rest-activity disruption in institutionalized patients with Alzheimer's disease

BACKGROUND

Disturbances in rest-activity rhythm are prominent and disabling symptoms in Alzheimer's disease (AD). Nighttime sleep is severely fragmented and daytime activity is disrupted by multiple napping episodes. In most institutional environments, light levels are very low and may not be sufficient to entrain the circadian clock to the 24-hour day.

METHOD

The purpose of this randomized clinical trial was to test the effectiveness of timed bright light therapy in reducing rest-activity (circadian) disruption in institutionalized patients with AD. The experimental groups received either morning (9.30-10.30 am) or afternoon (3.30-4.30 pm) bright light exposure ( > or = 2500 lux in gaze direction) Monday through Friday for 10 weeks. The control group received usual indoor light (150-200 lux). Nighttime sleep, daytime wake, and rest-activity parameters were determined by actigraphy. Repeated measures analysis of variance was employed to test the primary study hypotheses.

RESULTS

Seventy institutionalized subjects with AD (mean age 84) completed the study. No significant differences in actigraphy-based measures of nighttime sleep or daytime wake were found between groups. Subjects in either experimental light condition evidenced a significantly (p < 0.01) more stable rest-activity rhythm acrophase over the 10-week treatment period compared to the control subjects whose rhythm phase delayed by over two hours.

CONCLUSIONS

One hour of bright light, administered to subjects with AD either in the morning or afternoon, did not improve nighttime sleep or daytime wake compared to a control group of similar subjects. However, exposure to one-hour of bright light in either the morning or afternoon may provide sufficient additional input to the circadian pacemaker to facilitate entrainment to the 24-hour day.

Effect of morning bright light treatment for rest-activity disruption in institutionalized patients with severe Alzheimer's disease

BACKGROUND

Disturbances in rest-activity rhythm are prominent and disabling symptoms in Alzheimer's disease (AD). Nighttime sleep is severely fragmented and daytime activity is disrupted by multiple napping episodes. In most institutional environments, light levels are very low and may not be sufficient to enable the circadian clock to entrain to the 24-hour day. The purpose of this randomized, placebo-controlled, clinical trial was to test the effectiveness of morning bright light therapy in reducing rest-activity (circadian) disruption in institutionalized patients with severe AD.

METHOD

Subjects (n = 46, mean age 84 years) meeting the NINCDS-ADRDA (National Institute of Neurological and Communicative Disorders and Stroke--the Alzheimer's Disease and Related Disorders Association) AD diagnostic criteria were recruited from two large, skilled nursing facilities in San Francisco, California. The experimental group received one hour (09:30-10:30) of bright light exposure (> or = 2500 lux in gaze direction) Monday through Friday for 10 weeks. The control group received usual indoor light (150-200 lux). Nighttime sleep efficiency, sleep time, wake time and number of awakenings and daytime wake time were assessed using actigraphy. Circadian rhythm parameters were also determined from the actigraphic data using cosinor analysis and nonparametric techniques. Repeated measures analysis of variance (ANOVA) was used to test the primary study hypotheses.

RESULTS AND CONCLUSION

Although significant improvements were found in subjects with aberrant timing of their rest-activity rhythm, morning bright light exposure did not induce an overall improvement in measures of sleep or the rest-activity in all treated as compared to control subjects. The results indicate that only subjects with the most impaired rest-activity rhythm respond significantly and positively to a brief (one hour) light intervention.

A multicenter, placebo-controlled trial of melatonin for sleep disturbance in Alzheimer's disease

OBJECTIVES

To determine the safety and efficacy of 2 dose formulations of melatonin for the treatment of insomnia in patients with Alzheimer's disease.

DESIGN

A multicenter, randomized, placebo-controlled clinical trial of 2 dose formulations of oral melatonin coordinated by the National Institute of Aging-funded Alzheimer's Disease Cooperative Study. Subjects with Alzheimer's disease and nighttime sleep disturbance were randomly assigned to 1 of 3 treatment groups: placebo, 2.5-mg slow-release melatonin, or 10-mg melatonin.

SETTING

Private homes and long-term care facilities.

PARTICIPANTS

157 individuals were recruited by 36 Alzheimer's disease research centers. Subjects with a diagnosis of Alzheimer's disease were eligible if they averaged less than 7 hours of sleep per night (as documented by wrist actigraphy) and had 2 or more episodes per week of nighttime awakenings reported by the caregiver.

MEASUREMENTS

Nocturnal total sleep time, sleep efficiency, wake-time after sleep onset, and day-night sleep ratio during 2- to 3-week baseline and 2-month treatment periods. Sleep was defined by an automated algorithmic analysis of wrist actigraph data.

RESULTS

No statistically significant differences in objective sleep measures were seen between baseline and treatment periods for the any of the 3 groups. Nonsignificant trends for increased nocturnal total sleep time and decreased wake after sleep onset were observed in the melatonin groups relative to placebo. Trends for a greater percentage of subjects having more than a 30-minute increase in nocturnal total sleep time in the 10-mg melatonin group and for a decline in the day-night sleep ratio in the 2.5-mg sustained-release melatonin group, compared to placebo, were also seen. On subjective measures, caregiver ratings of sleep quality showed improvement in the 2.5-mg sustained-release melatonin group relative to placebo. There were no significant differences in the number or seriousness of adverse events between the placebo and melatonin groups.

CONCLUSIONS

Based on actigraphy as an objective measure of sleep time, melatonin is not an effective soporific agent in people with Alzheimer's disease.

Effectiveness of strategies to manage sleep in residents of aged care facilities

BACKGROUND

The promotion of sleep in older adults is a significant issue in high-level residential aged care facilities, with as many as 67% of residents experiencing disruptions to their sleep patterns. Not only do health concerns such as cognitive impairment, pain and incontinence impact upon this population's sleep quality and quantity, but environmental factors including noise, light and night-time nursing care also affect sleep of those residing in institutions. In order to address the issue of sleep disruption, assessment and diagnosis of sleep problems and implementation of interventions that are effective in promoting sleep are essential.

OBJECTIVES

The objective of this review was to determine the most effective tools for the assessment and diagnosis of sleep in older adults in high-level aged care. The review also sought to determine the most effective strategies for the promotion of sleep in this population. Outcome measures for this review were: indicators of improved sleep quality and quantity, including an improvement in daytime functioning and improved night-time sleep; reduction in use of hypnotics and sedatives; and increased satisfaction with sleep.

SEARCH STRATEGY

A literature search was performed using the following databases for the years 1993-2003: AgeLine, APAIS Health, CINAHL, Cochrane Library, Current Contents, Dissertation Abstracts International, Embase, Medline, Proquest, PsycInfo, Science Citations Index. A second search stage was conducted through review of reference lists of studies retrieved during the first search stage. The search was limited to published and unpublished material in English language.

SELECTION CRITERIA

The review was limited to papers addressing sleep diagnosis, assessment and/or management in adults aged 65 or over who were residing in high-level aged care. The review included randomised controlled trials (RCTs) and, due to the limited number of RCTs available, non-RCTs, cohort and case control studies and qualitative research were also considered for inclusion. Research was included if it addressed the assessment, diagnosis or management of sleep using outcome measure of improved night-time sleep or daytime function, improvements in resident satisfaction with sleep or reduction in medication use associated with sleep. The types of interventions considered by this review were alternative therapies including massage, aromatherapy and medicinal herbs; behavioural or cognitive interventions; biochemical interventions; environmental interventions; pharmacological interventions and related nocturnal interventions such as continence care. Instruments and strategies to diagnose and assess the sleep of older high-level care residents, including objective and subjective assessment tools, were considered by this review.

DATA COLLECTION AND ANALYSIS

All retrieved papers were critically appraised for eligibility for inclusion and methodological quality independently by two reviewers, and the same reviewers collected details of eligible research. Papers were grouped according to the type of intervention or type of assessment tool used and findings were presented in a narrative summary.

FINDINGS

Wrist actigraphy was found to be the most accurate objective sleep assessment tool for use in the population of interest, and issues surrounding its use are presented. Although no subjective sleep assessment tools were identified in this review, the evidence suggested that subjective reports of sleep quality are an important consideration in sleep assessment. Evidence suggested that behavioural observations may be an effective assessment strategy when conducted on a frequent basis. The review found no evidence on the effectiveness of any assessment tools for the diagnosis of specific sleep problems in older adults. The use of multidisciplinary strategies including reduction of environmental noise, reduction of night-time nursing care that disrupts sleep and daytime activity is likely to be the most effective strategy for the promotion of sleep in older high-level care residents. The use of sedating medications did not appear to have a substantial effect in promoting sleep, and health practitioners in high-level aged care should consider their use cautiously.