Risk of dementia in patients with primary insomnia: a nationwide population-based case-control study

A Cross Sectional Survey of Factors Related to Cannabis Use as a Sleep Aid Among Canadian Cancer Survivors

OBJECTIVES

Poor sleep is a common side effect of cancer. Cannabis is increasingly used to manage cancer treatment-related symptoms, including sleep. This study investigated factors related to cannabis use for sleep among Canadian cancer survivors.

METHOD

Adult Canadian cancer survivors (N = 940) were recruited via the Angus Reid Institute and completed an online, cross-sectional survey. Univariate and multiple binomial logistic regression models identified factors associated with cannabis use for sleep.

RESULTS

Of the participants (Mage = 64.5 yrs; Women = 51.1%; White = 92.9%), 25.1% (n = 236) currently use cannabis for sleep. Participants were at greater odds of using cannabis for sleep if they identified as a gender other than man or woman (AOR = 11.132), were diagnosed with multiple medical conditions (2:AOR = 1.988; 3+:AOR = 1.902), two psychological conditions (AOR = 2.171), multiple sleep disorders (AOR = 2.338), insomnia (AOR = 1.942), bone (AOR = 6.535), gastrointestinal (AOR = 4.307), genitourinary (AOR = 2.586), hematological (AOR = 4.739), or an unlisted cancer (AOR = 3.470), received hormone therapy only (AOR = 3.054), drink heavily (AOR = 2.748), or had mild insomnia (AOR = 1.828). Older participants (AOR=.972) and those with sleep apnea were less likely to use cannabis for sleep (AOR=.560).

CONCLUSION

Given its prevalence, research is needed to understand how factors associated with cannabis use as a sleep aid among Canadian cancer survivors may influence its use and effectiveness and whether these factors are barriers to accessing evidence-based treatments.

Mental health problems raise the odds of cognitive impairment in COVID-19 survivors

Background

COVID-19 survivors around the globe are suffering from mental health issues. While mental health problems can be an early warning sign of dementia, they may also increase the chances of developing the disease. In this study, we examined the mental health of COVID-19 survivors and mapped its associations with cognitive and demographic variables.

Method

COVID-19 survivors listed in the databases of three tertiary care hospitals in Kolkata were contacted sequentially. 376 willing patients were interviewed over the telephone. 99 COVID-19 patients and 31 matched controls participated in the in-person interviews that were arranged for a more detailed investigation. The participants were administered standardized tests that are widely used for the assessment of cognitive functioning and mental health status.

Result

64.89% of COVID-19 survivors reported a deterioration in physical functioning. 44.95% reported a decline in mental health, whereas 41.49% reported a drop in cognitive performance. Detailed investigations revealed that they had an increased risk of having depression, anxiety, and poor sleep quality by 91%, 68%, and 140%, respectively. 6.1% of the patients had mild cognitive impairment, and 4% had dementia. COVID-19 patients who had depression and anxiety were 8.6 and 19.4 times more likely to have cognitive decline, respectively. Compared to the matched controls, COVID-19 patients had greater depression (p<.001), anxiety (p<.001), stress (p =.003), and insomnia (p <.001). They also scored significantly lower on Addenbrooke's Cognitive Examination-III (p =.009) and Picture Naming Test (p =.005) and took significantly longer to complete Trail Making Test-A (p =.002).

Conclusion

COVID-19 survivors in this study had major mental health issues even one year after contracting the virus. They had significant cognitive deficits that might progress into dementia. Strict monitoring and systematic treatment plans should be implemented as soon as possible.

Causal relationship between sleep disorders and the risk of Alzheimer's disease: A Mendelian randomization study

BACKGROUND AND OBJECTIVE

Epidemiological studies have shown that sleep disorders are risk factors for Alzheimer's disease (AD), but the causal relationship between sleep disorders and AD risk is unknown. We aim to assess the potential genetic causal association between sleep characteristics and AD, which may contribute to early identification and prediction of risk factors for AD.

METHODS

Seven sleep-related traits and the outcome phenotype AD were selected from published genome-wide association studies (GWASs). These sleep-related characteristics and instrumental variables (IVs) for AD were extracted. Two-sample and multivariate Mendelian randomization (MR) analyses were performed to assess the causal relationships between sleep characteristics and AD. The inverse variance weighted (IVW), weighted median (WME), weighted mode (WM), MR-Egger regression (MR-Egger) and simple mode (SM) models were used to evaluate causality. The existence of pleiotropy was detected and corrected by MR-Egger regression, MR pleiotropy residuals and outliers.

RESULTS

A two-sample MR study revealed a positive causal association between sleep duration and the onset of AD (OR = 1.002, 95 % CI: 1.000-1.004), and the risk of AD increased with increasing sleep duration. The MR-Egger regression method and MR-PRESSO were used to identify and correct pleiotropy, indicating that there was no horizontal pleiotropy. Heterogeneity was evaluated by Cochran's Q, which indicated no heterogeneity. In a multivariate MR study with seven sleep characteristics corrected for each other, we found that sleep duration remained causally associated with AD (OR = 1.004, 95 % CI: 1.000-1.007). Moreover, we found that after mutual correction, daytime napping had a causal relationship with the onset of AD, and daytime napping may reduce the risk of AD (OR = 0.995, 95 % CI: 0.991-1.000).

CONCLUSION

This study is helpful for the early identification and prediction of risk factors for AD, long sleep durations are a risk factor for AD, and daytime napping can reduce the risk of AD.

Role of Thymoquinone on sleep restriction and its mitigating effect on leptin-mediated signaling pathway in rat brain

BACKGROUND

Sleep and stress interact bidirectionally by acting on brain circuits that affect metabolism. Sleep and its alterations have impact on blood leptin levels, metabolic hormone that regulates appetite. Brain expresses the receptors for the peptide hormone leptin produced from adipocytes. The hypothalamic orexin neurons are low during sleep and active when awake, influenced by a complex interaction with leptin. Thymoquinone was found to be the major bioactive component of Nigella sativa. The aim of this study was to study the role of thymoquinone on sleep restriction and its mitigating effect on leptin-mediated signaling pathway in rat brain.

METHODS AND RESULTS

30 adult male Wistar rats were divided into 5 groups with 6 animals in each group: Control; Thymoquinone (TQ); Corn oil; Chronic Sleep restriction (CSR); and CSR + TQ. After 30 days, behavioral analysis, antioxidant, lipid profile, glucose level, liver and kidney function test, neurotransmitters, neuropeptides, and mRNA expression in in vivo studies were also assessed and pharmacokinetic and docking were done for thymoquinone. Thymoquinone has also shown good binding affinity to the target proteins. CSR has induced oxidative stress in the discrete brain regions and plasma. Current study has shown many evidences that sleep restriction has altered the neurobehavioral, antioxidant status, lipid profile, neurotransmitters, neuropeptide levels, and feeding behavior which damage the Orexin-leptin system which regulates the sleep and feeding that leads to metabolic dysfunction.

CONCLUSION

The potentiality of Thymoquinone was revealed in in silico studies, and its action in in vivo studies has proved its effectiveness. The study concludes that Thymoquinone has exhibited its effect by diminishing the metabolic dysfunction by its neuroprotective, antioxidant, and hypolipidemic properties.

Contribution of CNS and extra-CNS infections to neurodegeneration: a narrative review

Central nervous system infections have been suggested as a possible cause for neurodegenerative diseases, particularly sporadic cases. They trigger neuroinflammation which is considered integrally involved in neurodegenerative processes. In this review, we will look at data linking a variety of viral, bacterial, fungal, and protozoan infections to Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis and unspecified dementia. This narrative review aims to bring together a broad range of data currently supporting the involvement of central nervous system infections in the development of neurodegenerative diseases. The idea that no single pathogen or pathogen group is responsible for neurodegenerative diseases will be discussed. Instead, we suggest that a wide range of susceptibility factors may make individuals differentially vulnerable to different infectious pathogens and subsequent pathologies.

High serum Cholesterol and Triglyceride levels in older adults: associations with sleep and nighttime behavior disorders at baseline and a prediction analysis of incidental cases at 12 months follow-up

Introduction

This study explored the association between dyslipidemia and sleep and nighttime behavior disorders (SNBD) in the elderly.

Methods

ADNI population with complete Cholesterol, Triglyceride, SNBD, and neurocognitive data were included. Logistic regression was performed to study the association between dyslipidemia and SNBD at baseline and 12 months. Relevant confounders were adjusted for.

Results

Among the 2,216 included cases, 1,045 (47%) were females, and the median age was 73 (IQR: 68, 78). At baseline, 357 (16%) had SNBD, and 327 (18%) at 12 months; 187 were incident cases.There were more cases of baseline SNBD in the hypertriglyceridemia group than in those without (19% vs. 14%, p-value=0.003). Similarly, more follow-up SNBD cases had hypertriglyceridemia at baseline (21% vs. 16%, p-value=0.025). SNBD cases at baseline had significantly higher serum Triglyceride levels than those without (132 vs. 118mg/dL, p-value<0.001).Only hypertriglyceridemia was significantly associated with baseline SNBD (crude OR=1.43, 95%CI: 1.13,1.80, p-value=0.003), even after adjustment for confounding factors (adj.OR=1.36, 95%CI: 1.06,1.74, p-value=0.016) and (BMI-adj.OR=1.29, 95%CI: 1.00,1.66, p-value=0.048). None of the dyslipidemia forms did predict incident cases at 12 months.

Conclusions

Hypertriglyceridemia, but not hypercholesterolemia, was associated with higher odds of SNBD. None of the dyslipidemia forms predicted incidental SNBD over 12 months.

The mechanisms of mitochondrial abnormalities that contribute to sleep disorders and related neurodegenerative diseases

Sleep is a highly intricate biological phenomenon, and its disorders play a pivotal role in numerous diseases. However, the specific regulatory mechanisms remain elusive. In recent years, the role of mitochondria in sleep disorders has gained considerable attention. Sleep deprivation not only impairs mitochondrial morphology but also decreases the number of mitochondria and triggers mitochondrial dysfunction. Furthermore, mitochondrial dysfunction has been implicated in the onset and progression of various sleep disorder-related neurological diseases, especially neurodegenerative conditions. Therefore, a greater understanding of the impact of sleep disorders on mitochondrial dysfunction may reveal new therapeutic targets for neurodegenerative diseases. In this review, we comprehensively summarize the recent key findings on the mechanisms underlying mitochondrial dysfunction caused by sleep disorders and their role in initiating or exacerbating common neurodegenerative diseases. In addition, we provide fresh insights into the diagnosis and treatment of sleep disorder-related diseases.

Traditional Chinese medicine for insomnia: Recommendation mapping of the global clinical guidelines

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese Medicine (TCM) represents a rich repository of empirically-developed traditional medicines. The findings call for more rigorous study into the efficacy, safety, and mechanisms of action of TCM remedies to strengthen the evidence base.

AIM OF THE STUDY

To systematically review the quality of insomnia clinical practice guidelines that involve TCM recommendations and to summarize the certainty of evidence supporting the recommendations, strength, and consistency of recommendations, providing valuable research references for the development of future insomnia guidelines.

MATERIALS AND METHODS

We systematically searched PubMed, Web of Science, Embase, CNKI, Wanfang, Chinese Biomedical Literature Database, Chinese Medical Association, Chinese Sleep Research Society, Medsci, Medlive, British National Institute of Health and Clinical Excellence (NICE), and the International Guidelines Collaboration Network (GIN) for clinical practice guidelines on insomnia from inception to March 5, 2023. Four evaluators conducted independent assessments of the quality of the guidelines by employing the AGREE II tool. Subsequently, the guideline recommendations were consolidated and presented as evidence maps.

RESULTS

Thirteen clinical practice guidelines addressing insomnia, encompassing 211 recommendations (consisting of 127 evidence-based and 84 expert consensus recommendations), were deemed eligible for inclusion in our analysis. The evaluation results revealed an overall suboptimal quality, with the "scope and purpose" domain achieving the highest score (58.1%), while the "applicability" domain garnered the lowest score (13.0%). Specifically, it was observed that 74.8% (n = 95) of the evidence-based recommendations were supported by evidence of either very low or low certainty, in contrast to the expert consensus recommendations, which accounted for 61.9% (n = 52). We subsequently synthesized 44 recommendations into four evidence maps, focusing on proprietary Chinese medicines, Chinese medicine prescriptions, acupuncture, and massage, respectively. Notably, Chinese herbal remedies and acupuncture exhibited robust support, substantiated by high-certainty evidence, exemplified by interventions such as Xuefu Zhuyu decoction, spleen decoction, body acupuncture, and ear acupuncture, resulting in solid recommendations. Conversely, proprietary Chinese medicines needed more high-certainty evidence, predominantly yielding weak recommendations. As for other therapies, the level of certainty was predominantly categorized as low or very low. Recommendations about magnetic therapy, bathing, and fumigation relied primarily on expert consensus, needing more substantive clinical research evidence, consequently forming weak recommendations. Hot ironing and acupoint injection recommendations were weakly endorsed, primarily based on observational studies. Furthermore, interventions like qigong, gua sha, and moxibustion displayed a relatively limited number of clinical studies, necessitating further exploration to ascertain their efficacy.

CONCLUSIONS

Our analysis revealed a need for substantial improvement in the quality of all the included guidelines related to insomnia. Notably, recommendations for Traditional Chinese Medicine (TCM) treatments predominantly rely on low-certainty evidence. This study represents a pioneering effort in the utilization of recommendation mapping to both present and identify existing gaps in the evidence landscape within TCM therapies, thus setting the stage for future research initiatives. The evidence supporting TCM therapy recommendations must be fortified to achieve a more substantial level of recommendation and higher certainty. Consequently, there exists a critical and pressing demand for high-quality clinical investigations dedicated to TCM, with a specific focus on ascertaining its long-term efficacy, safety, and potential side effects in the context of insomnia treatment. These endeavors are poised to establish a robust scientific foundation to inform the development of TCM therapy recommendations within the insomnia guidelines.

Impaired sleep is associated with tau deposition on 18F-flortaucipir PET and accelerated cognitive decline, accounting for medications that affect sleep

BACKGROUND

Impaired sleep is commonly associated with Alzheimer's disease (AD), although the underlying mechanisms remain unclear. Furthermore, the moderating effects of sleep-affecting medications, which have been linked to AD pathology, are incompletely characterized. Using data from the Alzheimer's Disease Neuroimaging Initiative, we investigated whether a medical history of impaired sleep, informant-reported nighttime behaviors, and sleep-affecting medications are associated with beta-amyloid and tau deposition on PET and cognitive change, cross-sectionally and longitudinally.

METHODS

We included 964 subjects with 18F-florbetapir PET scans. Measures of sleep impairment and medication use were obtained from medical histories and the Neuropsychiatric Inventory Questionnaire. Multivariate models, adjusted for covariates, were used to assess associations among sleep-related features, beta-amyloid and tau, and cognition. Cortical tau deposition, categorized by Braak stage, was assessed using the standardized uptake value peak alignment (SUVP) method on 18F-flortaucipir PET.

RESULTS

Medical history of sleep impairment was associated with greater baseline tau in the meta-temporal, Braak 1, and Braak 4 regions (p = 0.04, p < 0.001, p = 0.025, respectively). Abnormal nighttime behaviors were also associated with greater baseline tau in the meta-temporal region (p = 0.024), and greater cognitive impairment, cross-sectionally (p = 0.007) and longitudinally (p < 0.001). Impaired sleep was not associated with baseline beta-amyloid (p > 0.05). Short-term use of selective serotonin reuptake inhibitors and benzodiazepines slightly weakened the sleep-tau relationship.

CONCLUSIONS

Sleep impairment was associated with tauopathy and cognitive decline, which could be linked to increased tau secretion from neuronal hyperactivity. Clinically, our results help identify high-risk individuals who could benefit from sleep-related interventions aimed to delay cognitive decline and AD.

Sleep disturbances as risk factors for neurodegeneration later in life

The relationship between sleep disorders and neurodegeneration is complex and multi-faceted. Using over one million electronic health records (EHRs) from Wales, UK, and Finland, we mined biobank data to identify the relationships between sleep disorders and the subsequent manifestation of neurodegenerative diseases (NDDs) later in life. We then examined how these sleep disorders' severity impacts neurodegeneration risk. Additionally, we investigated how sleep attributed risk may compensate for the lack of genetic risk factors (i.e. a lower polygenic risk score) in NDD manifestation. We found that sleep disorders such as sleep apnea were associated with the risk of Alzheimer's disease (AD), amyotrophic lateral sclerosis, dementia, Parkinson's disease (PD), and vascular dementia in three national scale biobanks, with hazard ratios (HRs) ranging from 1.31 for PD to 5.11 for dementia. These sleep disorders imparted significant risk up to 15 years before the onset of an NDD. Cumulative number of sleep disorders in the EHRs were associated with a higher risk of neurodegeneration for dementia and vascular dementia. Sleep related risk factors were independent of genetic risk for Alzheimer's and Parkinson's, potentially compensating for low genetic risk in overall disease etiology. There is a significant multiplicative interaction regarding the combined risk of sleep disorders and Parkinson's disease. Poor sleep hygiene and sleep apnea are relatively modifiable risk factors with several treatment options, including CPAP and surgery, that could potentially reduce the risk of neurodegeneration. This is particularly interesting in how sleep related risk factors are significantly and independently enriched in manifesting NDD patients with low levels of genetic risk factors for these diseases.

HIGHLIGHTS

Sleep disorders, particularly sleep apnea, are associated with the risk of Alzheimer's disease, amyotrophic lateral sclerosis, dementia, Parkinson's disease, and vascular dementia in national scale biobanks.These sleep disorders imparted significant risk up to 15 years before the onset of a neurodegenerative disease.The cumulative number of sleep disorders in the electronic health records were associated with a higher risk of neurodegeneration related to dementia and vascular dementia.Sleep related risk factors are independent of genetic risk for Alzheimer's and Parkinson's, potentially compensating for low genetic risk in overall disease etiology.Significant multiplicative interaction exists regarding the combined risk of sleep disorders and Parkinson's disease.

A cross-sectional survey of the prevalence and patterns of using cannabis as a sleep aid in Canadian cancer survivors

PURPOSE

Poor sleep is one of the most common side effects of cancer. It can persist for years beyond treatment and negatively impact quality of life and health. Cannabis is increasingly used to manage cancer treatment-related symptoms, including sleep. This study investigated the use and perceived effects of cannabis as a sleep aid in Canadian cancer survivors.

METHODS

Adult Canadian cancer survivors (N = 1464) were recruited via the Angus Reid Institute and completed an online, cross-sectional survey including the Insomnia Severity Index and questions about cannabis use for sleep. Standard descriptive statistics, such as means, standard deviations, and ranges were produced for measured variables to assess the ways cancer survivors use cannabis for sleep. Frequencies were tabulated for categorical and ordinal variables.

RESULTS

On average, participants (Mage = 61.1 years; Women = 50%: Men = 48%) received their cancer diagnosis 12.5 years prior. Of participants, 23.5% (n = 344) currently use cannabis as a sleep aid, with reported benefits including relaxation, reduced time to fall asleep, fewer nocturnal awakenings and improved sleep quality. Two thirds (68.3%, n = 235) only began using cannabis for sleep after their cancer diagnosis. Over a third of participants (36.3%, n = 125) use cannabis as a sleep aid every day. Among the 344, the most common other reasons for using cannabis were pain (31.4%, n = 108), recreational use (24.4%, n = 84), and anxiety (12.5%, n = 43).

CONCLUSIONS

Given the prevalence and potential impact, research is needed to examine the actual efficacy of cannabis as a sleep aid.

IMPLICATIONS FOR CANCER SURVIVORS

It is important that cancer survivors have information on methods to help their sleep to avoid impairments to quality of life and health.

Modified Suanzaoren decoction in treating post-stroke cognitive impairment with comorbid insomnia symptoms: A clinical trial

BACKGROUND

Cognitive impairment and insomnia are common complications for stroke patients, and often coexist without effective therapy. Modified Suanzaoren decoction (M-SZRD), derived from a famous classic prescription, has been used as an alternative treatment for these patients. The objective of this study is to investigate the effectiveness of M-SZRD in treating post-stroke cognitive impairment with comorbid insomnia symptoms.

METHODS

A total of 80 participants were randomly assigned into 2 groups to 40 cases in the treatment group (treated with modified Suanzaoren decoction) and 40 cases in the control group (treated with zolpidem). The intervention period was 4 weeks. Cognitive function, sleep quality, depression, and anxiety disorders were evaluated in both groups before and after treatment. Clinical assessment of patients with stroke included National Institutes of Health Stroke Scale and Barthel Index evaluations. Hormone levels of the hypothalamic-pituitary-adrenal and hypothalamus-pituitary-thyroid axis were also measured.

RESULTS

Out of the total 80 participants, 5 withdrew during the experiment and did not complete the study, leaving 75 patients for analysis to 38 in the treatment group and 37 in the control group. The findings showed that M-SZRD was more effective than the control group in improving cognitive function (P = .006). However, both groups were found to have a similar effect in improving insomnia (P = .323). There was no significant difference between the 2 groups in terms of activities of daily living and National Institutes of Health Stroke Scale improvement. M-SZRD was superior to the control group in improving depression state (P = .034), but when including dropouts in the intention-to-treat analysis, the difference was not statistically significant (P = .150). Furthermore, the M-SZRD group was better than the control group in reducing cortisol levels (P = .036), and the improvement in serum-free triiodothyronine (FT3) levels was also more significant in the M-SZRD group than in the control group (P = .0007).

CONCLUSION

M-SZRD is a more effective treatment for improving cognitive function in patients with post-stroke cognitive impairment and comorbid insomnia symptoms, possibly by regulating the cortisol levels of the hypothalamic-pituitary-adrenal axis and FT3 levels of the hypothalamus-pituitary-thyroid axis.

Neuroprotective effects of the PPARβ/δ antagonist GSK0660 in in vitro and in vivo Parkinson's disease models

BACKGROUND

The underlying mechanism of Parkinson's disease are still unidentified, but excitotoxicity, oxidative stress, and neuroinflammation are considered key actors. Proliferator activated receptors (PPARs) are transcription factors involved in the control of numerous pathways. Specifically, PPARβ/δ is recognized as an oxidative stress sensor, and we have previously reported that it plays a detrimental role in neurodegeneration.

METHODS

Basing on this concept, in this work, we tested the potential effects of a specific PPARβ/δ antagonist (GSK0660) in an in vitro model of Parkinson's disease. Specifically, live-cell imaging, gene expression, Western blot, proteasome analyses, mitochondrial and bioenergetic studies were performed. Since we obtained promising results, we tested this antagonist in a 6-hydroxydopamine hemilesioned mouse model. In the animal model, behavioral tests, histological analysis, immunofluorescence and western blot of substantia nigra and striatum upon GSK0660 were assayed.

RESULTS

Our findings suggested that PPARβ/δ antagonist has neuroprotective potential due to neurotrophic support, anti-apoptotic and anti-oxidative effects paralleled to an amelioration of mitochondria and proteasome activity. These findings are strongly supported also by the siRNA results demonstrating that by silencing PPARβ/δ a significative rescue of the dopaminergic neurons was obtained, thus indicating an involvement of PPARβ/δ in PD's pathogenesis. Interestingly, in the animal model, GSK0660 treatment confirmed neuroprotective effects observed in the in vitro studies. Neuroprotective effects were highlighted by the behavioural performance and apomorphine rotation tests amelioration and the reduction of dopaminergic neuronal loss. These data were also confirmed by imaging and western blotting, indeed, the tested compound decreased astrogliosis and activated microglia, concomitant with an upregulation of neuroprotective pathways.

CONCLUSIONS

In summary, PPARβ/δ antagonist displayed neuroprotective activities against 6-hydroxydopamine detrimental effects both in vitro and in vivo models of Parkinson's disease, suggesting that it may represent a novel therapeutic approach for this disorder.

The Devastating Effects of Sleep Deprivation on Memory: Lessons from Rodent Models

In this narrative review article, we discuss the role of sleep deprivation (SD) in memory processing in rodent models. Numerous studies have examined the effects of SD on memory, with the majority showing that sleep disorders negatively affect memory. Currently, a consensus has not been established on which damage mechanism is the most appropriate. This critical issue in the neuroscience of sleep remains largely unknown. This review article aims to elucidate the mechanisms that underlie the damaging effects of SD on memory. It also proposes a scientific solution that might explain some findings. We have chosen to summarize literature that is both representative and comprehensive, as well as innovative in its approach. We examined the effects of SD on memory, including synaptic plasticity, neuritis, oxidative stress, and neurotransmitters. Results provide valuable insights into the mechanisms by which SD impairs memory function.

Insomnia and risk of dementia in a large population-based study with 11-year follow-up: The HUNT study

Despite evidence suggesting that insomnia is associated with the risk of dementia and cognitive dysfunction, studies have shown mixed results. Dementia has a long prodromal phase, and studies with long follow-up are required to avoid reverse causality. In our 11-year follow-up study, we assessed whether probable insomnia disorder (PID) based on diagnostic criteria, and insomnia symptoms were associated with risk of all-cause dementia, Alzheimer's disease (AD) and cognition, measured with the Montreal Cognitive Assessment scale. We also examined if Apolipoprotein E genotype modified any associations with dementia through interaction. We analysed data from 7492 participants in the Norwegian Trøndelag Health Study. PID was not associated with all-cause dementia (odds ratio = 1.03, 95% confidence interval = 0.74-1.43), AD (odds ratio = 1.07, 95% confidence interval = 0.71-1.60) or Montreal Cognitive Assessment score (regression coefficient = 0.37, 95% confidence interval = -0.06 to 0.80). The insomnia symptom "difficulties maintaining sleep" was associated with a lower risk of all-cause dementia (odds ratio = 0.81, 95% confidence interval = 0.67-0.98), AD (odds ratio = 0.73, 95% confidence interval = 0.57-0.93), and better Montreal Cognitive Assessment score, mean 0.40 units (95% confidence interval = 0.15-0.64). No interaction with Apolipoprotein E genotype was found. PID and insomnia symptoms did not increase the risk of dementia in our study. More research with longer follow-up is needed, and future studies should explore if the associations to dementia risk vary across insomnia subtypes.

Insomnia Symptoms and Biomarkers of Alzheimer's Disease in the Community

BACKGROUND

Insomnia is one of the most common sleep disorders yet its relationship to the biology of Alzheimer's disease remains equivocal.

OBJECTIVE

We investigated the cross-sectional relationship between insomnia symptom severity and cerebrospinal fluid (CSF) concentrations of Alzheimer's disease biomarkers in a cognitively unimpaired middle-aged community sample.

METHODS

A total of 63 participants from the Healthy Brain Project (age = 59±7 years; 67% women) completed a lumbar puncture and two weeks of actigraphy to measure two of insomnia's core features: difficulty initiating sleep (prolonged sleep onset latency) and difficulty maintaining sleep (wake after sleep onset [WASO] and number of awakenings). Additionally, the Insomnia Severity Index (ISI) was completed by 58 participants. Linear and Tobit regression were used to estimate the associations between each insomnia variable and CSF Aβ42, phosphorylated tau 181 (p-tau181), total-tau, and neurofilament light chain protein (NfL), adjusting for age, sex, and APOEɛ4 genotype.

RESULTS

Higher ISI score was associated with greater average levels of CSF Aβ42 (per point: 30.7 pg/mL, 95% CI: 4.17-57.3, p = 0.023), as was higher WASO (per 10 min: 136 pg/mL, 95% CI: 48-223, p = 0.002) and more awakenings (per 5:123 pg/mL, 95% CI = 55-192, p < 0.001). Difficulty initiating sleep was not associated with CSF Aβ42, nor were insomnia features associated with p-tau181, total-tau, or NfL levels.

CONCLUSION

Insomnia symptoms were associated with higher CSF Aβ42 levels in this relatively young, cognitively unimpaired sample. These findings may reflect increased amyloid production due to acute sleep disruption.

Association Between Psychological Distress and Incident Dementia in a Population-Based Cohort in Finland

IMPORTANCE

Symptoms of psychological distress have shown association with subsequent dementia, but the nature of association remains unclear.

OBJECTIVE

To examine the association of psychological distress with etiological risk of dementia and incidence of dementia in presence of competing risk of death.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study consisted of population-based cross-sectional National FINRISK Study surveys collected in 1972, 1977, 1982, 1987, 1992, 1997, 2002, and 2007 in Finland with register-based follow-up; and the cohort was linked to Finnish Health Register data for dementia and mortality for each participant until December 31, 2017. Participants included individuals without dementia who had complete exposure data. Data were analyzed from May 2019 to April 2022.

EXPOSURES

Self-reported symptoms of psychological distress: stress (more than other people), depressive mood, exhaustion, and nervousness (often, sometimes, never).

MAIN OUTCOMES AND MEASURES

Incident all-cause dementia, ascertained through linkage to national health registers. Poisson cause-specific hazard model (emphasizing etiological risk) and Fine-Gray subdistribution hazard model (emphasizing effect on incidence) considering dementia and death without dementia as competing risks. Covariates of age, sex, baseline year, follow-up time, educational level, body mass index, smoking, diabetes, systolic blood pressure, cholesterol, and physical activity. Sensitivity analysis was performed to reduce reverse causation bias by excluding individuals with follow-up less than 10 years.

RESULTS

Among 67 688 participants (34 968 [51.7%] women; age range, 25 to 74 years; mean [SD] age, 45.4 years), 7935 received a diagnosis of dementia over a mean follow-up of 25.4 years (range, 10 to 45 years). Psychological distress was significantly associated with all-cause dementia in a multivariable Poisson model, with incidence rate ratios from 1.17 (95% CI, 1.08-1.26) for exhaustion to 1.24 (95% CI, 1.11-1.38) for stress, and remained significant in sensitivity analyses. A Fine-Gray model showed significant associations (with hazard ratios from 1.08 [95% CI, 1.01-1.17] for exhaustion to 1.12 [95% CI, 1.00-1.25] for stress) for symptoms other than depressive mood (hazard ratio, 1.08 [95% CI, 0.98-1.20]). All the symptoms showed significant associations with competing risk of death in both models.

CONCLUSIONS AND RELEVANCE

In this cohort study, psychological distress symptoms were significantly associated with increased risk of all-cause dementia in the model emphasizing etiological risk. Associations with real incidence of dementia were diminished by the competing risk of death.

Insomnia symptom severity and cognitive performance: Moderating role of APOE genotype

INTRODUCTION

We evaluated whether insomnia symptom severity was associated with cognitive function, and whether this relationship was modified by biomarkers associated with Alzheimer's disease risk.

METHODS

We examined insomnia symptoms and neuropsychological performance 3.4 years later in 511 dementia-free Framingham Heart Study participants (62.65 ± 8.7 years, 50.9% male). Additionally, we explored insomnia symptoms combined with self-reported short habitual sleep duration and effect modification by apolipoprotein E (APOE) ε4 allele status.

RESULTS

More severe insomnia symptoms were associated with lower performance on global cognition, and immediate and delayed Logical Memory recall, especially when insomnia symptoms were combined with short sleep duration. The association between insomnia symptoms and poorer memory recall was more pronounced in APOE ε4 allele carriers.

DISCUSSION

Insomnia symptom severity was associated with worse subsequent global cognitive and memory performance, which was especially apparent in APOE ε4 allele carriers, suggesting that poor sleep might be particularly detrimental when the brain is already vulnerable to neurodegeneration.

Fall Risk, Healthcare Resource Use, and Costs Among Adult Patients in the United States Treated for Insomnia with Zolpidem, Trazodone, or Benzodiazepines: A Retrospective Cohort Study

INTRODUCTION

Falls are a common cause for morbidity and mortality among patients taking prescription insomnia medication. The objective of this study is to compare the risk of falls, all-cause healthcare resource utilization (HCRU), and costs among patients treated with commonly used, older generation insomnia medications and non-sleep-disordered controls.

METHODS

This retrospective cohort study used the IBM^® MarketScan^® Commercial and Medicare Supplemental Databases to identify patients aged at least 18 years treated with commonly prescribed medications for insomnia (zolpidem, trazodone, benzodiazepines) between 1 January 2012 and 30 September 2017. The insomnia-treated cohort were age- and sex-matched (1:1) to non-sleep-disordered controls. Odds ratios (ORs) compared risk of falls in each cohort, adjusting for covariates. Costs were adjusted to 2018 dollars, the most recent year for the study data.

RESULTS

Relative to matched controls (n = 313,086), the insomnia-treated cohort had a higher rate of falls (3.34% vs. 1.33%), and higher risk of falls [OR = 2.36 (95% confidence interval 2.27-2.44)]. Relative to other index treatments, patients treated with trazodone had the greatest risk of falls. Compared with matched controls, the estimated mean number of inpatient visits, emergency department visits, outpatient visits, and mean length of inpatient stay were all significantly higher among patients treated for insomnia. Such patients incurred greater total costs per patient per month than matched controls ($2100 versus $888; estimated mean ratio, 2.36; 95% CI 2.35-2.38; p < 0.0001).

CONCLUSIONS

Relative to matched controls, the insomnia-treated cohort showed higher risk of falls with greater HCRU and costs. Each outcome measured was highest among patients treated with trazodone, relative to other index treatments. Findings suggest the need for new treatment options to optimize quality of care for patients with insomnia.

Sleep-Disordered Breathing Risk with Comorbid Insomnia Is Associated with Mild Cognitive Impairment

Introduction: Few studies have evaluated the combined association between SDB with comorbid insomnia and mild cognitive impairment (MCI). To test the hypothesis that SDB with comorbid insomnia is associated with greater odds of MCI than either sleep disorder independently, we used ADNI data to evaluate cross-sectional associations between SDB risk with comorbid insomnia status and MCI. Methods: Participants with normal cognition or MCI were included. Insomnia was defined by self-report. SDB risk was assessed by modified STOP-BANG. Logistic regression models evaluated associations between four sleep disorder subgroups (low risk for SDB alone, low risk for SDB with insomnia, high risk for SDB alone, and high risk for SDB with insomnia) and MCI. Models adjusted for age, sex, BMI, APOE4 genotype, race, ethnicity, education, marital status, hypertension, cardiovascular disease, stroke, alcohol abuse, and smoking. Results: The sample (n = 1391) had a mean age of 73.5 ± 7.0 years, 44.9% were female, 72.0% were at low risk for SDB alone, 13.8% at low risk for SDB with insomnia, 10.1% at high risk for SDB alone, and 4.1% at high risk for SDB with insomnia. Only high risk for SDB with comorbid insomnia was associated with higher odds of MCI (OR 3.22, 95% CI 1.57–6.60). Conclusion: Studies are needed to evaluate SDB with comorbid insomnia as a modifiable risk factor for MCI.

Insomnia symptom subtypes and manifestations of prodromal neurodegeneration: a population-based study in the Canadian Longitudinal Study on Aging

STUDY OBJECTIVES

To identify the association between insomnia symptoms and signs of prodromal neurodegeneration, including an analysis of potential differences between sleep-onset and sleep-maintenance insomnia.

METHODS

We included those aged 45-85 years, living in 1 of 10 Canadian provinces between 2012 and 2015 (at the baseline), recruited via 3 population-based sampling methods. Insomnia symptoms were assessed using questions adapted/modified from the Pittsburgh Sleep Quality Index. A panel of potential prodromal neurodegenerative markers including self-reported symptoms and objective gait motor, cognitive, and autonomic variables were assessed cross sectionally. We compared those who endorsed insomnia symptoms ≥ 3 times per week to controls, adjusting for age, sex, and education via logistic regression.

RESULTS

Overall, 2,051/30,097 people screened positive for sleep-onset insomnia alone and 4,333 for sleep-maintenance insomnia alone, while 2,371 endorsed both subtypes. On objective gait tests, participants with sleep-onset insomnia, but not sleep-maintenance insomnia, had worse balance (odds ratio [OR] = 1.33, 95% confidence interval = [1.16, 1.52]) and slower gait speed (OR = 1.52 [1.34, 1.73]). Although participants with any insomnia subtype endorsed more motor symptoms, these were more severe in those with sleep-onset insomnia (OR onset vs maintenance = 1.13 [1.07, 1.18]). On objective cognitive tests, those with sleep-maintenance insomnia scored normally. However, participants with sleep-onset insomnia performed worse on tests of verbal fluency (OR = 1.24 [1.06, 1.43]), immediate memory (OR = 1.23 [1.08, 1.41]), and prospective memory task (OR = 1.29 [1.11, 1.50]). The sleep-onset insomnia group also had lower heart rate variability (OR = 1.23 [1.07, 1.43]). Secondary analyses found generally similar results in young vs older age of insomnia development.

CONCLUSIONS

Compared to maintenance insomnia, those with sleep-onset insomnia have more motor, cognitive, and autonomic signs/symptoms. When evaluating neurodegenerative risk, differentiating insomnia subtypes may increase precision.

CITATION

Yao CW, Pelletier A, Fereshtehnejad S-M, Cross N, Dang-Vu T, Postuma RB. Insomnia symptom subtypes and manifestations of prodromal neurodegeneration: a population-based study in the Canadian Longitudinal Study on Aging. J Clin Sleep Med. 2022;18(2):345-359.

Joint effects of self-reported sleep and modifiable physical activity on risk of dyslipidaemia in women aged 45-55 years: a cross-sectional study

OBJECTIVES

Modifiable physical activity (PA) plays an important role in dyslipidaemia risk in middle-aged women with sleep problems, especially perimenopausal women. We aimed to explore the joint effects of sleep and PA on the risk of dyslipidaemia in women aged 45-55 years, and the extent to which PA moderated the effect of sleep on the risk of dyslipidaemia.

DESIGN

A cross-sectional study.

SETTING

This study was based on the survey of Chronic Disease and Nutrition Monitoring in Adults in Inner Mongolia in 2015.

PARTICIPANTS

721 women aged 45-55 years were included.

OUTCOME MEASUREMENT

PA was measured by the Global Physical Activity Questionnaire. Sleep was measured by questionnaire formulated by the Chinese Center for Disease Control and Prevention. Multivariate logistic regression analyses were performed to determine the joint effects of sleep and PA on dyslipidaemia risk. OR and 95% CI were reported.

RESULTS

Among all participants, 60.6% had sleep problems, 29.0% had low PA and 41.1% had dyslipidaemia. Women with sleep problems had higher dyslipidaemia risk than women without sleep problems, irrespective of low, moderate or high PA, with OR (95% CI) of 4.24 (2.40 to 7.49), 3.14 (1.80 to 5.49) and 2.04 (1.20 to 3.48), respectively. PA could not completely attenuate the negative association between sleep and dyslipidaemia risk. With PA increased from low to high, the OR of dyslipidaemia decreased by 2.20. Women with sleep problems and low PA had higher risks of high total cholesterol, high triglyceride, low high-density lipoprotein cholesterol and high low-density lipoprotein cholesterol than women without sleep problems and high PA, with OR (95% CI) of 2.51 (1.18 to 5.35), 2.42 (1.23 to 4.74), 2.88 (1.44 to 5.74) and 2.52 (1.12 to 5.70), respectively.

CONCLUSIONS

Among women aged 45-55 years, the joint effects of self-reported sleep and PA on dyslipidaemia risk were more marked for sleep than for PA. Modifiable PA is a widely accessible and effective intervention to reduce the dyslipidaemia risk in women with sleep problems, particularly among perimenopausal women.

Sleep Disturbances, Cognitive Status, and Biomarkers of Dementia

BACKGROUND

While sleep disturbances appear to be risk factors in Alzheimer's disease (AD) progression, information such as the prevalence across dementia severity and the influence on the trajectory of cognitive decline is unclear.

OBJECTIVE

We evaluate the hypotheses that the prevalence of insomnia differs by cognitive impairment, that sleep disturbances track with AD biomarkers, and that longitudinal changes in sleep disorders affect cognition.

METHODS

We used the National Alzheimer's Coordinating Center Database to determine the prevalence of clinician-identified insomnia and nighttime behaviors in normal, mild cognitive impairment (MCI), and demented individuals. We evaluated mean Montreal Cognitive Assessment (MoCA) scores, hippocampal volumes (HV), and CSF phosphorylated tau:amyloid-β ratios at first visit using analysis of variance with age as a covariate. In longitudinal evaluations, we assessed changes in MoCA scores and HV in insomnia and nighttime behaviors between the first and last visits.

RESULTS

Prevalence of insomnia was 14%, 16%, and 11% for normal, MCI, and dementia groups. Prevalence of nighttime behaviors was 14%, 21%, and 29% respectively. Insomnia patients had higher MoCA scores, larger HV, and lower pTauBeta than individuals without insomnia, indicating less neurodegeneration. In contrast, nighttime behaviors were associated with worse cognition, smaller HV, and higher pTauBeta. Similar findings were seen between longitudinal associations of sleep disorders and cognition and HV.

CONCLUSION

Our findings suggest that insomnia is unreliably recognized in patients with cognitive impairment. Nighttime behaviors may better indicate the presence of sleep disturbances and have diagnostic specificity in AD over insomnia.

A Review of Insomnia Treatments for Patients with Mild Cognitive Impairment

Mild cognitive impairment (MCI) impacts approximately 20% of older adults, with many also experiencing sleep disorders, such as insomnia. Given the relationship between sleep and dementia, addressing sleep issues may offer an opportunity to treat reversible causes. There are two primary treatments for insomnia: behavioral-based (cognitive behavioral therapy for insomnia, CBT-I) and pharmacological interventions. Although CBT-I is recommended as first-line treatment for insomnia in older adults, sedative-hypnotics are more likely to be recommended than non-pharmacological treatments given their convenience and accessibility. However, there are significant concerns in prescribing medications to patients with MCI. To explore this disconnect, we reviewed insomnia treatments in older adults with MCI studies and current guidelines of pharmacological therapy. First, we reviewed studies presenting non-pharmacological treatment of insomnia in older adults with MCI. Although the search yielded over 4,000 non-duplicate titles, only one article presented data on non-pharmacological treatment of insomnia in MCI. The literature covering comorbid insomnia, CBT-I, and MCI is sparse. In contrast to review of non-pharmacological studies, studies on the pharmacological treatment of insomnia in older adults were ample. Finally, we reviewed international guidelines for pharmacological treatment of insomnia in cognitive disorders. More widely used pharmacological interventions show short-term effectiveness with problems of recurrence, ineffectiveness in inadvertent or purposeful chronic use, and adverse side effects. Despite evidence regarding adverse consequences, pharmacological treatment of insomnia remains the most common treatment for insomnia. Reflecting on age-related changes in older adults, particularly those with MCI, inappropriate or mismanagement of medication can lead to unnecessary complications. Further research examining effective behavioral-based sleep management options in older adults with cognitive impairment is needed with exploration of improved sleep on cognitive function.

Risks and Prognoses of Alzheimer's Disease and Vascular Dementia in Patients With Insomnia: A Nationwide Population-Based Study

This study aimed to investigate the risk and prognosis of Alzheimer's disease (AD) and vascular dementia (VaD) in patients with insomnia using the National Health Insurance Service database covering the entire population of the Republic of Korea from 2007 to 2014. In total, 2,796,871 patients aged 40 years or older with insomnia were enrolled, and 5,593,742 controls were matched using a Greedy digit match algorithm. Mortality and the rate of admission to a long-term care facility were estimated using multivariable Cox analysis. Of all patients with insomnia, 138,270 (4.94%) and 26,706 (0.96%) were newly diagnosed with AD and VaD, respectively. The incidence rate ratios for AD and VaD were 1.73 and 2.10, respectively, in patients with insomnia compared with those without. Higher mortality rates and long-term care facility admission rates were also observed in patients with dementia in the insomnia group. Known cardiovascular risk factors showed interactions with the effects of insomnia on the risk of AD and VaD. However, the effects of insomnia on the incidence of AD and VaD were consistent between the groups with and without cardiovascular risk factors. Insomnia is a medically modifiable and policy-accessible risk factor and prognostic marker of AD and VaD.

White matter microstructural abnormalities in primary insomnia: A systematic review of diffusion tensor imaging studies

Primary insomnia (PI), the most common sleep disorder, is primarily characterized by difficulties in initiating and maintaining sleep and deficits in daytime functioning. Study of white matter (WM) connections of the brain might provide valuable information regarding the underlying neural mechanism of PI. Diffusion tensor imaging (DTI) provides non-invasive access to the microstructural and network properties of brain WM, and thus, a great opportunity to quantitatively and sensitively study the human brain. The current literature of PI does not provide a consistent explanation of the etiology and pathology of the disorder; thus, we searched PubMed, EMBASE, and SCOPUS for DTI studies that compared WM integrity or network organization between PI patients and healthy controls to integrate all existing literature as an insight for further studies, and, hopefully, effective prevention and management of the disorder. English peer-reviewed full-text publications that investigated the diffusion indices of PI patients or those with insomnia symptoms compared with a group of healthy controls were included. We included 11 studies and extracted the data for qualitative synthesis. Except for one study, all studies were rated as high-quality, based on quality assessment. In aggregation, a total of 541 patients with PI and 679 healthy controls were included in this study. Our review of DTI studies suggests that WM disruptions in PI are better characterized in the context of neural networks. Frontostriatal, frontothalamic, and corticocortiscal networks, as well as the limbic system, seem to be the main neural networks with microstructural and network alterations in patients with PI. To illustrate, different parts of corona radiate and internal capsule within the corticosubcortical networks and superior longitudinal fasciculus within the corticocortical networks showed altered microstructural properties in PI patients. In view of the fact that the findings from individual studies are heterogeneous, it is difficult to derive consistent findings from the results, and the divergence of the findings must not be disregarded. Thus, this study is a starting point for future studies, and its implications for etiology and pathogenesis of insomnia should be regarded cautiously.

Effects of Chinese herbal medicines on dementia risk in patients with sleep disorders in Taiwan

ETHNOPHARMACOLOGICAL RELEVANCE

Sleep disorders affect an estimated 150 million people worldwide and result in adverse health, safety, and work performance-related outcomes that have important economic consequences. In Taiwan, Chinese herbal medicine (CHM) is a complementary natural medicine and has been widely used as an adjunctive therapy.

AIM OF THE STUDY

This study aimed to investigate the effect of CHM on dementia risk in patients with sleep disorders in Taiwan.

MATERIALS AND METHODS

We identified 124,605 patients with sleep disorders between the ages of 20 and 60 years. Of these, 5876 CHM users and 5876 non-CHM users were matched according to age and gender. The chi-squared test, Cox proportional hazard model, Kaplan-Meier method, and log-rank test were used for the comparisons. Association rule mining and network analysis were applied to determine a CHM pattern specialized for sleep disorders.

RESULTS

More CHM users did not use sleeping pills than non-CHM users. CHM users had a lower risk of dementia than non-CHM users after adjusting for age, gender, and sleeping pill use (hazard ratio (HR): 0.469, 95% CI = 0.289-0.760; p-value = 0.002). The cumulative incidence of dementia was lower among CHM users (long-rank test, p-value < 0.001). Association rule mining and network analysis showed that Ye-Jiao-Teng (YJT; Caulis Polygoni Multiflori; Polygonum multiflorum Thunb), Suan-Zao-Ren-Tang (SZRT), Jia-Wei-Xiao-Yao-San (JWXYS), He-Huan-Pi (HHP; Cortex Albizziae; Albizia julibrissin Durazz.), and Suan-Zao-Ren (SZR; Semen Zizyphi Spinosae; Ziziphus jujuba Mill.) were important CHMs for patients with sleep disorders in Taiwan.

CONCLUSIONS

A comprehensive list of herbal medicines may be useful for the clinical treatment of patients with sleep disorders, and for future scientific investigations into the prevention of dementia in these patients.

Time-Varying Insomnia Symptoms and Incidence of Cognitive Impairment and Dementia among Older US Adults

There is conflicting evidence regarding the association between insomnia and the onset of mild cognitive impairment (MCI) or dementia. This study aimed to evaluate if time-varying insomnia is associated with the development of MCI and dementia. Data from the Health and Retirement Study (n = 13,833) from 2002 to 2014 were used (59.4% female). The Brief Insomnia Questionnaire was used to identify insomnia symptoms which were compiled in an insomnia severity index, ranging from 0 to 4. In analysis, participants' symptoms could vary from wave-to-wave. Dementia was defined using results from the Health and Retirement Study (HRS) global cognitive assessment tool. Respondents were classified as either having dementia, MCI, or being cognitively healthy. Cox proportional hazards models with time-dependent exposure using the counting process (start-stop time) were used for analysis. For each one-unit increase in the insomnia symptom index, there was a 5-percent greater hazard of MCI (HR = 1.05; 95% CI: 1.04-1.06) and dementia (HR = 1.05; 95% CI: 1.03-1.05), after fully adjusting. Using a nationally representative sample of adults age 51 and older, this study found that time-varying insomnia symptoms are associated with risk of MCI and dementia. This highlights the importance of identifying sleep disturbances and their change over time as potentially important risk factors for MCI and dementia.

Effect of Caffeine Consumption on the Risk for Neurological and Psychiatric Disorders: Sex Differences in Human

Caffeine occurs naturally in various foods, such as coffee, tea, and cocoa, and it has been used safely as a mild stimulant for a long time. However, excessive caffeine consumption (1~1.5 g/day) can cause caffeine poisoning (caffeinism), which includes symptoms such as anxiety, agitation, insomnia, and gastrointestinal disorders. Recently, there has been increasing interest in the effect of caffeine consumption as a protective factor or risk factor for neurological and psychiatric disorders. Currently, the importance of personalized medicine is being emphasized, and research on sex/gender differences needs to be conducted. Our review focuses on the effect of caffeine consumption on several neurological and psychiatric disorders with respect to sex differences to provide a better understanding of caffeine use as a risk or protective factor for those disorders. The findings may help establish new strategies for developing sex-specific caffeine therapies.

The effect of insomnia on development of Alzheimer's disease

Alzheimer's disease (AD) is the most common type of dementia and a neurodegenerative disorder characterized by memory deficits especially forgetting recent information, recall ability impairment, and loss of time tracking, problem-solving, language, and recognition difficulties. AD is also a globally important health issue but despite all scientific efforts, the treatment of AD is still a challenge. Sleep has important roles in learning and memory consolidation. Studies have shown that sleep deprivation (SD) and insomnia are associated with the pathogenesis of Alzheimer's disease and may have an impact on the symptoms and development. Thus, sleep disorders have decisive effects on AD; this association deserves more attention in research, diagnostics, and treatment, and knowing this relation also can help to prevent AD through screening and proper management of sleep disorders. This study aimed to show the potential role of SD and insomnia in the pathogenesis and progression of AD.

Insomnia and obstructive sleep apnea as potential triggers of dementia: is personalized prediction and prevention of the pathological cascade applicable?

INTRODUCTION

Sleep disorders ultimately result in sleep deficiency and poor-quality adversely impacts the immune system, glucose metabolism, body weight control, cardiovascular and cerebrovascular function, cognitive function, psychological stability, work productivity, quality of life, and social safety. Sleep disorders are very common among the elderly and are often comorbid with other diseases such as dementia, and further accelerating the underlying neurodegenerative processes. Initial studies have not clearly revealed the relationship between sleep disorders and dementia. Nonetheless, recent findings have suggested that insomnia and obstructive sleep apnea (OSA) are closely associated with dementia and perhaps they could be good predictors of occurrence of dementia and optimal treatments for sleep deficiencies may prevent or delay the onset dementia.

METHODS

Here, we conducted a systematic review based on the criteria of predictive, preventive, and personalized medicine on the association of dementia in elderlies with sleep disorder, namely insomnia and OSA. We included 7432 studies and analyzed a total of 14 publications after applying appropriate exclusion criteria.

RESULTS

We found that OSA patients had a large tendency to develop and/or experience accelerations of both Alzheimer's disease (AD) and also vascular dementia, whereas insomnia patients only develop and/or experience accelerations of AD. This may be reflected in the fact that AD and vascular dementia have similar and at the same time also different mechanisms of action. Several studies have also revealed that treating sleep disorders in elderly patients prevented or delayed the onset of dementia, mitigating the progression of symptoms in patients who already manifested dementic symptoms and even reversing neurodegeneration in particular brain areas.

DISCUSSION

Currently, the general medical consensus has poorly addressed the role of sleep disorders in exacerbating the risk of dementia. Critically, studies such as the present one emphasizes that the treatment of sleep disorders could be one the preventive measures to evade or to improve dementia symptoms. Additionally, elderly individuals often manifest different sleep deficiency symptoms than younger ones. Given this, an improved age-specific categorization and evaluation methods for sleep deficiency need to be implemented in diagnosing dementia in order to enable personalized assessments and treatments. Collectively, these findings may also assist to improve efforts in predictively detecting and eventually treating dementia.

Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) for chronic insomnia disorder ('CANSLEEP' trial): protocol for a randomised, placebo-controlled, double-blinded, proof-of-concept trial

INTRODUCTION

Insomnia is a highly prevalent and costly condition that is associated with increased health risks and healthcare utilisation. Anecdotally, cannabis use is frequently reported by consumers to promote sleep. However, there is limited research on the effects of cannabis on sleep and daytime function in people with insomnia disorder using objective measures. This proof-of-concept study will evaluate the effects of a single dose of an oral cannabis-based medicine on sleep and daytime function in participants with chronic insomnia disorder.

METHODS AND ANALYSIS

A randomised, crossover, placebo-controlled, single-dose study design will be used to test the safety and efficacy of an oral oil solution ('ETC120') containing 10 mg Δ9-tetrahydrocannabinol (THC) and 200 mg cannabidiol (CBD) in 20 participants diagnosed with chronic insomnia disorder. Participants aged 35-60 years will be recruited over an 18-month period commencing August 2019. Each participant will receive both the active drug and matched placebo, in a counterbalanced order, during two overnight study assessment visits, with at least a 1-week washout period between each visit. The primary outcomes are total sleep time and wake after sleep onset assessed via polysomnography. In addition, 256-channel high-density electroencephalography and source modelling using structural brain MRI will be used to comprehensively examine brain activation during sleep and wake periods on ETC120 versus placebo. Next-day cognitive function, alertness and simulated driving performance will also be investigated.

ETHICS AND DISSEMINATION

Ethics approval was received from Bellberry Human Research Ethics Committee (2018-04-284). The findings will be disseminated in a peer-reviewed open-access journal and at academic conferences.

TRIAL REGISTRATION NUMBER

ANZCTRN12619000714189.

Head Position During Sleep: Potential Implications for Patients with Neurodegenerative Disease

BACKGROUND

The characterization of sleep in those with neurodegenerative disease (NDD) is essential in understanding the potential neurobiological mechanisms that underlie the connection between sleep disruption and NDD manifestations and progression.

OBJECTIVE

Explore the inter-relationships between NDD and age, sex, diagnosis of obstructive sleep apnea, snoring, and duration of sleep time with the head in the supine and non-supine positions.

METHODS

A case-control design was used to evaluate differences in sleep position obtained from multi-night, in-home Sleep Profiler recordings in 45 patients with diagnosed NDD (24 with mild cognitive impairment, 15 with Alzheimer's disease, and 6 with Lewy Body, Parkinson's, or other dementias) and 120 age-sex matched controls with normal cognition (NC).

RESULTS

The frequency of supine sleep >2 h/night was significantly greater in the NDD than in the NC group (p < 0.001, odds ratio = 3.7), and remained significant after controlling for age, sex, snoring, and obstructive sleep apnea diagnosis (p = 0.01). There were no group differences in nocturnal mobility i.e., number of head position changes/h.

CONCLUSION

This study demonstrates the utility of in-home measurements of sleep in defining the association of supine sleep position with neurodegenerative disorders. Our findings warrant further investigation, particularly in light of the recent evidence suggesting that sleep may an active role in the brain's ability to clear CNS neurotoxins and metabolites.

Impact of Sleep Disorder as a Risk Factor for Dementia in Men and Women

Sleep is an essential physiological process, especially for proper brain function through the formation of new pathways and processing information and cognition. Therefore, when sleep is insufficient, this can result in pathophysiologic conditions. Sleep deficiency is a risk factor for various conditions, including dementia, diabetes, and obesity. Recent studies have shown that there are differences in the prevalence of sleep disorders between genders. Insomnia, the most common type of sleep disorder, has been reported to have a higher incidence in females than in males. However, sex/gender differences in other sleep disorder subtypes are not thoroughly understood. Currently, increasing evidence suggests that gender issues should be considered important when prescribing medicine. Therefore, an investigation of the gender-dependent differences in sleep disorders is required. In this review, we first describe sex/gender differences not only in the prevalence of sleep disorders by category but in the efficacy of sleep medications. In addition, we summarize sex/gender differences in the impact of sleep disorders on incident dementia. This may help understand gender-dependent pathogenesis of sleep disorders and develop therapeutic strategies in men and women.

Neuroimaging insights into the link between depression and Insomnia: A systematic review

BACKGROUND

Insomnia is a common symptom of Major Depressive Disorder (MDD) and genome-wide association studies pointed to their strong genetic association. Although the prevalence of insomnia symptoms in MDD is noticeable and evidence supports their strong bidirectional association, the number of available neuroimaging findings on patients of MDD with insomnia symptoms is limited. However, such neuroimaging studies could verily improve our understanding of their shared pathophysiology and advance corresponding theories.

METHODS

Based on the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guideline, we have conducted a literature search using PubMed, EMBASE, and Scopus databases and systematically explored 640 studies using various neuroimaging modalities in MDD patients with different degrees of insomnia symptoms.

RESULTS

Despite inconsistencies, current findings from eight studies suggested structural and functional disturbances in several brain regions including the amygdala, prefrontal cortex and anterior cingulate cortex and insula. The aberrant functional connectivity within and between the main hubs of the salience and default mode networks could potentially yield new insights into the link between MDD and insomnia, which needs further assessment.

LIMITATIONS

The number of studies reviewed herein is limited. The applied methods for assessing structural and functional neural mechanisms of insomnia and depression were variable.

CONCLUSION

Neuroimaging methods demonstrated the overlapping underlying neural mechanisms between MDD and insomnia. Future studies may facilitate better understanding of their pathophysiology to allow development of specific treatment.

Insomnia in Older Adults

Purpose of Review

To evaluate and summarize recent research articles pertaining to insomnia in older adults that can guide healthcare providers on factors to consider when assessing and managing insomnia.

Recent Findings

Up to 75% of older adults experience symptoms of insomnia. Insomnia is associated with socioeconomic status, racial and ethnic classification, family relationships, medical and mental health disorders, cognitive function, and dementia. Although one-fifth of older adults are still prescribed sleep medications, cognitive behavioral therapy for insomnia is the first line treatment for insomnia, resulting in short-term and long-term benefits.

Summary

To manage insomnia safely and effectively, healthcare providers need to consistently assess for insomnia during baseline and annual assessments, evaluate medical and social factors associated with insomnia, minimize the use of sleep medications, and provide referrals to and/or collaborate with providers who perform cognitive behavioral therapy for insomnia. Insomnia screening is important as it facilitates early intervention with behavioral management, reduces the potential for pharmacological management, which increases fall risk in older adults, and enables further assessment and early identification of outcomes such as cognitive impairment.

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.

Cardiovascular health and sleep disturbances in two population-based cohort studies

OBJECTIVE

We aimed to investigate the association between cardiovascular health (CVH), as defined by the American Heart Association, and several sleep disturbances.

METHODS

Two community-based cohorts, the Paris Prospective Study 3 (PPS3, France, n=6441) and the CoLaus study (Switzerland, n=2989) were analysed. CVH includes 7 metrics which all can be classified as poor, intermediate and ideal. Global CVH score was categorised into poor (0-2 ideal metrics), intermediate (3-4 ideal metrics) and ideal (≥5 ideal metrics). Associations between global CVH and self-reported sleep disturbances (proxy of sleep-disordered breathing [SDB], excessive daytime sleepiness, insomnia symptoms and short/long sleep duration) and SDB severity measured by polysomnography (PSG) were investigated. Adjusted OR/relative risk ratio (RRR) and 95% CIs were estimated. Subjects with previous cardiovascular disease were excluded.

RESULTS

Compared with poor CVH, subjects with intermediate and ideal global CVH had lower odds of self-reported SDB in both cohorts (ORs 0.55; 95% CI 0.44 to 0.68 and 0.35; 95% CI 0.22 to 0.53, respectively) and had lower SDB severity measured by PSG (RRR 0.07; 95% CI 0.02 to 0.20) in CoLaus. Subjects with intermediate and ideal global CVH had lower odds of excessive daytime sleepiness in PPS3 (ORs 0.82; 0.72 to 0.95 and 0.80; 0.82 to 1.02, respectively). No consistent associations were found between CVH and sleep duration or insomnia symptoms.

CONCLUSIONS

Higher levels of CVH are associated with lower odds of SDB and excessive daytime sleepiness. However, causal interpretation cannot be made and associations might be bidirectional.

Auriculotherapy for sleep quality in people with primary insomnia: A protocol for a systematic review and meta-analysis

BACKGROUND

Primary insomnia is one of the common sleep disorders. Auriculotherapy originated from traditional Chinese medicine, has been thought as a promising treatment for primary insomnia. We aim to evaluate the efficacy and safety of auriculotherapy for patients with primary insomnia through this systematic review.

METHODS

Five English databases (Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, AMED, and CINAHL), 4 Chinese databases (CBM, CNKI, CQVIP, and Wanfang), and 5 clinical trial registration databases (ClinicalTrials.gov, ANZCTR, EU-CTR, ChiCTR, and ICTRP) will be searched from establishment of the database until November 2018. Articles written in English or Chinese languages will be included. The randomized controlled trials of auriculotherapy (auricular acupuncture and auricular acupressure) for patients with primary insomnia will be included. The primary outcome will be assessed according to the Pittsburgh sleep quality index. Meta-analysis will be conducted with the use of RevMan 5.3. The specific process will refer to the Cochrane Handbook 5.1 for Systematic Review.

RESULTS

High-quality synthesis of current evidence on the efficacy and safety of auriculotherapy for primary insomnia will be provided in this study.

CONCLUSION

This systematic review aims to present evidence for whether auriculotherapy is an effective intervention which can improve sleep quality in patients suffering primary insomnia.

PROSPERO REGISTRATION NUMBER

CRD42019106422.

Managing nocturia: The multidisciplinary approach

Nocturia, defined as waking at night to pass urine, is a common condition which increases with age. Whilst nocturia is known to have an important effect on quality of life, more recent evidence has linked the symptom with significant morbidity and mortality due to the effects of sleep deprivation on glucose metabolism and the immune system. The causes of nocturia are multifactorial and may be related to urine overproduction, storage disorders and primary sleep disorders. The commonest underlying pathology, however, is nocturnal polyuria, which may be associated with a number of medical conditions. This review explores the underlying causes of nocturia and nocturnal polyuria and, by doing so, describes a multidisciplinary approach to managing patients effectively.