Sleep-Wake Disorders in Stroke—Increased Stroke Risk and Deteriorated Recovery? An Evaluation on the Necessity for Prevention and Treatment

Vagus nerve stimulation in cerebral stroke: biological mechanisms, therapeutic modalities, clinical applications, and future directions

Stroke is a major disorder of the central nervous system that poses a serious threat to human life and quality of life. Many stroke victims are left with long-term neurological dysfunction, which adversely affects the well-being of the individual and the broader socioeconomic impact. Currently, post-stroke brain dysfunction is a major and difficult area of treatment. Vagus nerve stimulation is a Food and Drug Administration-approved exploratory treatment option for autism, refractory depression, epilepsy, and Alzheimer's disease. It is expected to be a novel therapeutic technique for the treatment of stroke owing to its association with multiple mechanisms such as altering neurotransmitters and the plasticity of central neurons. In animal models of acute ischemic stroke, vagus nerve stimulation has been shown to reduce infarct size, reduce post-stroke neurological damage, and improve learning and memory capacity in rats with stroke by reducing the inflammatory response, regulating blood-brain barrier permeability, and promoting angiogenesis and neurogenesis. At present, vagus nerve stimulation includes both invasive and non-invasive vagus nerve stimulation. Clinical studies have found that invasive vagus nerve stimulation combined with rehabilitation therapy is effective in improving upper limb motor and cognitive abilities in stroke patients. Further clinical studies have shown that non-invasive vagus nerve stimulation, including ear/cervical vagus nerve stimulation, can stimulate vagal projections to the central nervous system similarly to invasive vagus nerve stimulation and can have the same effect. In this paper, we first describe the multiple effects of vagus nerve stimulation in stroke, and then discuss in depth its neuroprotective mechanisms in ischemic stroke. We go on to outline the results of the current major clinical applications of invasive and non-invasive vagus nerve stimulation. Finally, we provide a more comprehensive evaluation of the advantages and disadvantages of different types of vagus nerve stimulation in the treatment of cerebral ischemia and provide an outlook on the developmental trends. We believe that vagus nerve stimulation, as an effective treatment for stroke, will be widely used in clinical practice to promote the recovery of stroke patients and reduce the incidence of disability.

Sleep disorders as both risk factors for, and a consequence of, stroke: A narrative review

BACKGROUND AND PURPOSE

Sleep disorders are increasingly implicated as risk factors for stroke, as well as a determinant of stroke outcome. They can also occur secondary to the stroke itself. In this review, we describe the variety of different sleep disorders associated with stroke and analyze their effect on stroke risk and outcome.

METHODS

A search term-based literature review ("sleep," "insomnia," "narcolepsy," "restless legs syndrome," "periodic limb movements during sleep," "excessive daytime sleepiness" AND "stroke" OR "cerebrovascular" in PubMed; "stroke" and "sleep" in ClinicalTrials.gov) was performed. English articles from 1990 to March 2023 were considered.

RESULTS

Increasing evidence suggests that sleep disorders are risk factors for stroke. In addition, sleep disturbance has been reported in half of all stroke sufferers; specifically, an increase is not only sleep-related breathing disorders but also periodic limb movements during sleep, narcolepsy, rapid eye movement (REM) sleep behavior disorder, insomnia, sleep duration, and circadian rhythm sleep-wake disorders. Poststroke sleep disturbance has been associated with worse outcome.

CONCLUSION

Sleep disorders are risk factors for stroke and associated with worse stroke outcome. They are also a common consequence of stroke. Recent guidelines suggest screening for sleep disorders after stroke. It is possible that treatment of sleep disorders could both reduce stroke risk and improve stroke outcome, although further data from clinical trials are required.

Development of insomnia in patients with stroke: A systematic review and meta-analysis

BACKGROUND AND AIM

Stroke is a serious threat to human life and health, and post-stroke insomnia is one of the common complications severely impairing patients' quality of life and delaying recovery. Early understanding of the relationship between stroke and post-stroke insomnia can provide clinical evidence for preventing and treating post-stroke insomnia. This study was to investigate the prevalence of insomnia in patients with stroke.

METHODS

The Web of Science, PubMed, Embase, and Cochrane Library databases were used to obtain the eligible studies until June 2023. The quality assessment was performed to extract valid data for meta-analysis. The prevalence rates were used a random-efect. I2 statistics were used to assess the heterogeneity of the studies.

RESULTS

Twenty-six studies met the inclusion criteria for meta-analysis, with 1,193,659 participants, of which 497,124 were patients with stroke.The meta-analysis indicated that 150,181 patients with stroke developed insomnia during follow-up [46.98%, 95% confidence interval (CI): 36.91-57.18] and 1806 patients with ischemic stroke (IS) or transient ischemic attack (TIA) developed insomnia (47.21%, 95% CI: 34.26-60.36). Notably, 41.51% of patients with the prevalence of nonclassified stroke developed insomnia (95% CI: 28.86-54.75). The incidence of insomnia was significantly higher in patients with acute strokes than in patients with nonacute strokes (59.16% vs 44.07%, P < 0.0001).Similarly, the incidence of insomnia was significantly higher in the patients with stroke at a mean age of ≥65 than patients with stroke at a mean age of <65 years (47.18% vs 40.50%, P < 0.05). Fifteen studies reported the follow-up time. The incidence of insomnia was significantly higher in the follow-up for ≥3 years than follow-up for <3 years (58.06% vs 43.83%, P < 0.05). Twenty-one studies used the Insomnia Assessment Diagnostic Tool, and the rate of insomnia in patients with stroke was 49.31% (95% CI: 38.59-60.06). Five studies used self-reporting, that the rate of insomnia in patients with stroke was 37.58% (95% CI: 13.44-65.63).

CONCLUSIONS

Stroke may be a predisposing factor for insomnia. Insomnia is more likely to occur in acute-phase stroke, and the prevalence of insomnia increases with patient age and follow-up time. Further, the rate of insomnia is higher in patients with stroke who use the Insomnia Assessment Diagnostic Tool.

Obstructive Sleep Apnea and Stroke: Determining the Mechanisms Behind their Association and Treatment Options

Sleep-disordered breathing (SDB) can be a sequela of stroke caused by vascular injury to vital respiratory centers, cerebral edema, and increased intracranial pressure of space-occupying lesions. Likewise, obstructive sleep apnea (OSA) contributes to increased stroke risk through local mechanisms such as impaired ischemic cerebrovascular response and systemic effects such as promoting atherosclerosis, hypercoagulability, cardiac arrhythmias, vascular-endothelial dysfunction, and metabolic syndrome. The impact of OSA on stroke outcomes has been established, yet it receives less attention in national guidelines on stroke management than hyperglycemia and blood pressure dysregulation. Furthermore, whether untreated OSA worsens stroke outcomes is not well-described in the literature. This scoping review provides an updated investigation of the correlation between OSA and stroke, including inter-relational pathophysiology. This review also highlights the importance of OSA treatment and its role in stroke outcomes. Knowledge of pathophysiology, the inter-relationship between these common disorders, and the impact of OSA therapy on outcomes affect the clinical management of patients with acute ischemic stroke. In addition, understanding the relationship between stroke outcomes and pre-existing OSA will allow clinicians to predict outcomes while treating acute stroke.

Deciphering Post-Stroke Sleep Disorders: Unveiling Neurological Mechanisms in the Realm of Brain Science

Sleep disorders are the most widespread mental disorders after stroke and hurt survivors' functional prognosis, response to restoration, and quality of life. This review will address an overview of the progress of research on the biological mechanisms associated with stroke-complicating sleep disorders. Extensive research has investigated the negative impact of stroke on sleep. However, a bidirectional association between sleep disorders and stroke exists; while stroke elevates the risk of sleep disorders, these disorders also independently contribute as a risk factor for stroke. This review aims to elucidate the mechanisms of stroke-induced sleep disorders. Possible influences were examined, including functional changes in brain regions, cerebrovascular hemodynamics, neurological deficits, sleep ion regulation, neurotransmitters, and inflammation. The results provide valuable insights into the mechanisms of stroke complicating sleep disorders.

A Systematic Review and Meta-Analysis on the Identification of Predictors Associated With Insomnia or Sleep Disturbance in Post-stroke Patients

The aim of this study was to identify the factors associated with sleep disturbances in individuals after a stroke. To systematically identify relevant studies, an extensive search strategy was devised. We conducted comprehensive searches in major electronic databases including PubMed, Embase, PsycINFO, and Cochrane Library. The search was limited to articles published in English between January 1, 2011, and February 10, 2024. Pooled effect estimates, such as odds ratio (OR) or mean difference (MD) along with their confidence interval (CIs), were calculated using random-effects models for categorical variables and continuous variables, respectively. A total of nine studies were included in this meta-analysis. The pooled prevalence of insomnia across the included studies was determined to be 40% (95% CI = 30%-49%), with individual study prevalence ranging from 22% to 72%. A pooled analysis showed that gender demonstrated a statistically significant association with sleep disturbance, with females exhibiting a higher likelihood (OR = 1.49, 95% CI = 1.16-1.91, p = 0.002) compared to males. The National Institutes of Health Stroke Scale (NIHSS) score, a measure of stroke severity, was associated with sleep disturbance (MD = 0.86, 95% CI = 0.56-1.17, p = 0.001), indicating that patients with severe strokes may be more prone to sleep disturbances. These findings underscore the importance of comprehensive evaluation and targeted interventions to address sleep-related issues in stroke patients, particularly those with severe neurological impairment.

Functional recovery after ischemic stroke: Impact of different sleep health parameters

Sleep disturbances after ischaemic stroke include alterations of sleep architecture, obstructive sleep apnea, restless legs syndrome, daytime sleepiness and insomnia. Our aim was to explore their impacts on functional outcomes at month 3 after stroke, and to assess the benefit of continuous positive airway pressure in patients with severe obstructive sleep apnea. Ninety patients with supra-tentorial ischaemic stroke underwent clinical screening for sleep disorders and polysomnography at day 15 ± 4 after stroke in a multisite study. Patients with severe obstructive apnea (apnea-hypopnea index ≥ 30 per hr) were randomized into two groups: continuous positive airway pressure-treated and sham (1:1 ratio). Functional independence was assessed with the Barthel Index at month 3 after stroke in function of apnea-hypopnea index severity and treatment group. Secondary objectives were disability (modified Rankin score) and National Institute of Health Stroke Scale according to apnea-hypopnea index. Sixty-one patients (71.8 years, 42.6% men) completed the study: 51 (83.6%) had obstructive apnea (21.3% severe apnea), 10 (16.7%) daytime sleepiness, 13 (24.1%) insomnia, 3 (5.7%) depression, and 20 (34.5%) restless legs syndrome. Barthel Index, modified Rankin score and Stroke Scale were similar at baseline and 3 months post-stroke in the different obstructive sleep apnea groups. Changes at 3 months in those three scores were similar in continuous positive airway pressure versus sham-continuous positive airway pressure patients. In patients with worse clinical outcomes at month 3, mean nocturnal oxygen saturation was lower whereas there was no association with apnea-hypopnea index. Poorer outcomes at 3 months were also associated with insomnia, restless legs syndrome, depressive symptoms, and decreased total sleep time and rapid eye movement sleep.

Examining the Role of GLU/GABA to GLN Metabolic Cycle in the Pathogenesis of Post-Stroke Depressive Disorder and Insomnia

Objective

This study aims to elucidate the potential links between the GLU/GABA to GLN metabolic cycle disruptions and the onset of depressive and insomnia disorders following a stroke. We particularly focus on understanding if these disorders share a common underlying pathogenic mechanism.

Methods

We examined 63 patients with post-stroke insomnia, 62 patients with post-stroke depression, and 18 healthy individuals. The study involved assessing insomnia using the Acute Insomnia Scale (AIS) and depression using the Hamilton Depression Rating Scale. We measured serum concentrations of GLN, GLU, and GABA and analyzed their correlations with AIS and HAMD scores.

Results

Our results indicate no significant difference in the serum levels of GLN, GLU, and GABA between the post-stroke insomnia and depression groups. However, these levels were notably lower in both patient groups compared to the healthy control group. A negative correlation between AIS scores and GABA levels was observed in the post-stroke insomnia group, suggesting a potential link between GABAergic disturbances and insomnia. Conversely, no significant correlation was found between Hamilton Depression Rating Scale scores and the levels of GABA, GLU, or GLN in the post-stroke depression group.

Conclusion

The study highlights that abnormalities in the GLU/GABA to GLN metabolic cycle, particularly the levels of GLN, GABA, and GAD, might be intricately linked to the pathogenesis of post-stroke insomnia and depression. Our findings suggest that GABAergic imbalances could be indicative of post-stroke insomnia, serving as potential biological markers for differential diagnosis in clinical settings. Further research is warranted to explore these relationships in greater depth, potentially leading to new diagnostic and therapeutic approaches for post-stroke neuropsychiatric disorders.

Comparative effectiveness of different treatments for post-stroke insomnia: A network meta-analysis

Background

：Post-stroke insomnia（PSI）is one of the common complications after stroke and it is a chronic problem and hampers the patient's recovery. Some treatments have been shown to be effective in treating post-stroke insomnia. However, it is not clear which treatment is more effective.

Methods

In this study, we searched CNKI, PubMed, and Cochrane Library for appropriate keywords with a deadline of October 2022 to select 23 randomized controlled trials（RCTs）. The mean difference between different treatments was assessed and summarized as mean and 95 % confidence interval (CI), resulting in a Bayesian network meta-analysis.

Results

By meta-analysis of Bayesian networks, we found acupuncture(MD, -2.49; 95 % CI, [-3.63, -1.31]) and herbal (MD, -2.79; 95 % CI, [-4.9, -0.69]) were significantly better than estazolam in terms of PSQI score change, and the difference was statistically significant. Dexzopiclone, electrics stimulation, rTMS and zopiclone were not statistically significant with other treatments.

Conclusion

Herbal, zopiclone, and acupuncture were more effective in improving PSQI scores in patients with post-stroke insomnia, followed by rTMS and dexzopiclone. However, the effectiveness between herbal, zopiclone and acupuncture was not statistically significant. Acupuncture and herbal are promising for the treatment of PSI, and more research remains to be invested.

An investigation on the changes of serum CCK-8, substance P, and 5-HT in patients with post-stroke insomnia

BACKGROUND

At present, the pathogenesis of post-stroke insomnia (PSI) is still inconclusive.

OBJECTIVE

To explore the changes and significance of serum cholecystokinin-8 (CCK-8), substance P (SP), and 5-hydroxytryptamine (5-HT) in patients with PSI.

METHODS

Ninety-one patients with stroke were selected as the research subjects, and according to the score of the Athens Insomnia Scale (AIS), they were divided into the insomnia group and the non-insomnia group. The serum levels of CCK-8, SP, and 5-HT in the two groups were compared to explore their relationships with PSI.

RESULTS

Among the 91 patients, 56 were in the insomnia group and 35 were in the non-insomnia group, and the incidence of insomnia was 61.5%. There was no significant difference in the serum levels of CCK-8, SP, and 5-HT between the two groups (P= 0.696, 0.980, and 0.809, respectively). One-way analysis of variance showed that there was no significant correlation between the serum levels of CCK-8, SP, 5-HT, and the AIS score (P= 0.7393, 0.9581, and 0.5952, respectively).

CONCLUSION

The incidence of PSI was relatively high, but it could not be proved that CCK-8, SP, and 5-HT were involved in the pathogenesis of PSI. There might exist other neurotransmitters involved in the pathophysiological process of PSI, which should be further explored.

Association of circadian rhythms with brain disorder incidents: a prospective cohort study of 72242 participants

Circadian rhythm disruption (CRD) is a shared characteristic of various brain disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD), and major depression disorder (MDD). Disruption of circadian rhythm might be a risk factor for brain disorder incidents. From 7-day accelerometry data of 72,242 participants in UK Biobank, we derived a circadian relative amplitude variable, which to some extent reflected the degree of circadian rhythm disruption. Records of brain disorder incidents were obtained from a wide range of health outcomes across self-report, primary care, hospital inpatient data, and death data. Using multivariate Cox proportional hazard ratio regression, we created two models adjusting for different covariates. Then, linear correlations between relative amplitude and several brain morphometric measures were examined in participants with brain MRI data. After a median follow-up of around 6.1 years, 72,242 participants were included in the current study (female 54.9%; mean age 62.1 years). Individuals with reduced relative amplitude had increasing risk of all-cause dementia (Hazard ratio 1.23 [95% CI 1.15 to 1.31]), PD (1.33 [1.25 to 1.41]), stroke (1.13 [1.06 to 1.22]), MDD (1.18 [1.13 to 1.23]), and anxiety disorder (1.14 [1.09 to 1.20]) in fully adjusted models. Additionally, significant correlations were found between several cortical regions and white matter tracts and relative amplitude that have been linked to dementia and psychiatric disorders. We confirm CRD to be a risk factor for various brain disorders. Interventions for regulating circadian rhythm may have clinical relevance to reducing the risk of various brain disorders.

Regional brain dysfunction in insomnia after ischemic stroke: A resting-state fMRI study

Objective

This study aimed to explore the abnormality of local brain function in patients with post-stroke insomnia (PSI) based on fMRI and explore the possible neuropathological mechanisms of insomnia in patients with PSI in combination with the Pittsburgh sleep quality index (PSQI) score and provide an objective evaluation index for the follow-up study of acupuncture treatment of PSI.

Methods

A total of 27 patients with insomnia after stroke were enrolled, and the PSQI was used to evaluate their sleep status. Twenty-seven healthy participants who underwent physical examinations during the same period were selected as controls. Resting-state brain function images and structural images of the two groups of participants were collected, and the abnormal changes in the regional brain function in patients with PSI were analyzed using three methods: regional homogeneity (ReHo), the amplitude of low-frequency fluctuations (ALFF) and fractional ALFF (fALFF), and a correlation analysis with the PSQI scale score.

Results

Compared with the HCs, the ReHo values of the PSI group in the bilateral lingual gyrus, right cuneus, right precentral and postcentral gyri were significantly lower, and the ReHo values of the left supramarginal gyrus were significantly higher. In the PSI group, the ALFF values in the bilateral lingual gyrus were significantly decreased, whereas those in the bilateral middle temporal gyrus, right inferior temporal gyrus, right inferior frontal gyrus, right limbic lobe, right precuneus, left posterior cingulate gyrus, and left middle occipital gyrus were significantly increased. Compared with HCs, the fALFF values of the bilateral lingual gyrus, bilateral inferior occipital gyrus, and bilateral cuneus in the PSI group were significantly higher. The ReHo value of the left supramarginal gyrus in the PSI group was significantly negatively correlated with the total PSQI score.

Conclusion

Patients with PSI have abnormal local activities in multiple brain regions, including the visual processing-related cortex, sensorimotor cortex, and some default-mode network (DMN) regions. Over-arousal of the DMN and over-sensitivity of the audiovisual stimuli in patients with PSI may be the main mechanisms of insomnia and can lead to a decline in cognitive function and abnormalities in emotion regulation simultaneously.

Non-invasive Vagus Nerve Stimulation in Cerebral Stroke: Current Status and Future Perspectives

Stroke poses a serious threat to human health and burdens both society and the healthcare system. Standard rehabilitative therapies may not be effective in improving functions after stroke, so alternative strategies are needed. The FDA has approved vagus nerve stimulation (VNS) for the treatment of epilepsy, migraines, and depression. Recent studies have demonstrated that VNS can facilitate the benefits of rehabilitation interventions. VNS coupled with upper limb rehabilitation enhances the recovery of upper limb function in patients with chronic stroke. However, its invasive nature limits its clinical application. Researchers have developed a non-invasive method to stimulate the vagus nerve (non-invasive vagus nerve stimulation, nVNS). It has been suggested that nVNS coupled with rehabilitation could be a promising alternative for improving muscle function in chronic stroke patients. In this article, we review the current researches in preclinical and clinical studies as well as the potential applications of nVNS in stroke. We summarize the parameters, advantages, potential mechanisms, and adverse effects of current nVNS applications, as well as the future challenges and directions for nVNS in cerebral stroke treatment. These studies indicate that nVNS has promising efficacy in reducing stroke volume and attenuating neurological deficits in ischemic stroke models. While more basic and clinical research is required to fully understand its mechanisms of efficacy, especially Phase III trials with a large number of patients, these data suggest that nVNS can be applied easily not only as a possible secondary prophylactic treatment in chronic cerebral stroke, but also as a promising adjunctive treatment in acute cerebral stroke in the near future.

Efficacy and safety evaluation of bright light therapy in patients with post-stroke insomnia: A protocol for systematic review and meta-analysis

BACKGROUND

Post-stroke insomnia (PSI) is a common and severe illness among the complications of stroke. Although there are plenty of drugs currently used for PSI treatment, they generate several side effects and other problems. Bright light therapy (BLT) is thought to be relatively safe and effective in treating PSI patients. Despite this, there is still a lack of systematic review on BLT in the treatment of PSI. Allowing for this, the aim of this study is to assess the efficacy and safety of BLT for PSI.

METHODS

The meta-analysis and systematic review will perform a comprehensive electronic search for items fulfilling the required criteria in Web of Science, Google Scholar, Wan Fang database, MEDLINE, Baidu Scholar, PubMed, SinoMed, Embase, Chinese Biomedical Literature Database (CBM), China national knowledge infrastructure database (CNKI), Cochrane Library Central Register of Controlled Trials (CENTRAL), and Wei Pu database from establishment to January 1, 2022. We will select articles, collect data, and assess the methodology quality. And we will set the primary outcome and secondary outcomes in this research. RevMan 5.3 software will be used to analyze the data for this investigation.

RESULTS

The work of this research will be published in peer-reviewed scientific journals.

CONCLUSION

The aim of this study is to assess the efficacy and safety of BLT for PSI and present robust scientific evidence concerning BLT for PSI.

REGISTRATION

INPLASY2021100065.

Effect of the Interaction between Depression and Sleep Disorders on the Stroke Occurrence: An Analysis Based on National Health and Nutritional Examination Survey

OBJECTIVE

To investigate the effect of the interaction between depression and sleep disorders on the stroke occurrence based on the data from the National Health and Nutritional Examination Survey (NHANES).

METHODS

Seven cycles of 2-year NHANES data (2005-2018) were analyzed in this study. Univariate analysis was first performed between the stroke and nonstroke patients, and then, multivariate logistic regression models were conducted to analyze the association of depression, sleep disorders, and their interactions with stroke occurrence.

RESULTS

A total of 30473 eligible participants were included in this study, including 1138 (3.73%) with stroke and 29335 (96.27%) with nonstroke. Except sex, the differences were all significant between the stroke and nonstroke patients in baseline information (all P < 0.001). Depression (odds ratio (OR): 2.494, 95% confidence interval (CI): 2.098-2.964), depression severity (moderate, OR: 2.013, 95% CI: 1.612-2.514; moderately severe, OR: 2.598, 95% CI: 1.930-3.496; severe, OR: 5.588, 95% CI: 3.883-8.043), and sleep disorders (OR: 1.677, 95% CI: 1.472-1.910) were presented to be associated with an increased risk of stroke after correcting all the confounders. The logistic regression analysis showed that there was a synergic, additive interaction between depression and sleep disorders on the stroke occurrence, and the proportion of stroke patients caused by this interaction accounted for 27.1% of all the stroke patients.

CONCLUSION

Depression, depression severity, and sleep disorders are all independently associated with a high risk of stroke. The interaction between depression and sleep disorders can synergistically increase the stroke occurrence.

Acupuncture Reduced the Risk for Insomnia in Stroke Patients: A Propensity-Score Matched Cohort Study

Background: Post-stroke insomnia (PSI) affects the quality of life for stroke patients, reduces the likelihood of successful rehabilitation, and produces additional complications following stroke. Previous reports have provided some information regarding PSI risk factors, but little is known concerning protective factors for PSI. This study analyzed the relationship between acupuncture and insomnia in stroke patients and explored the use of acupuncture as a preventive treatment.

Methods: Patients diagnosed with stroke from 2010 to 2019 were identified in the case database of the First Affiliated Hospital of Guangzhou University of Chinese These patients followed until 2020, and numerous factors were examined, including gender, age, stroke type, stroke location, and baseline comorbidities. A 1:1 propensity score was used to match an equal number of patients receiving acupuncture with stroke patients who did not receive acupuncture (N = 1,680 for each group). The purpose of the study was to compare the incidence of insomnia in these two stroke cohorts. We used the Cox regression model and Kaplan-Meier method to estimate the risk of insomnia as the outcome event.

Results: Compared with the non-acupuncture cohort in general, stroke patients who received acupuncture treatment exhibited a lower risk of insomnia after adjusting for age, gender, stroke type, stroke location, and comorbidities (adjusted hazard ratio HR = 0.27, 95% confidential interval = 0.23 to 0.32). Acupuncture also reduced the risk of PSI for both genders. The respective risks were HR = 0.28 (adjusted) for males and HR = 0.26 (adjusted) for females. Acupuncture also lowered the risk for PSI for different age groups. The risks were HR = 0.22 (adjusted) for individuals 18 to 39 years of age, HR = 0.31 (adjusted) for individuals 40 to 59 years of age, HR = 0.28 (adjusted) for those 60 to 79 years of age, and HR = 0.18 (adjusted) for individuals 80 years of age and older. Concerning the stroke type, regardless of whether the stroke was ischemic, hemorrhagic, or a combination of the two stroke types, patients who received acupuncture exhibited lower risk (adjusted HR = 0.28, 0.17, and 0.49, respectively). Concerning stroke location, except for the cerebral hemispheres (adjusted HR = 1.10, 95% confidential interval = 0.12 to 1.01), the risk of PSI after receiving acupuncture was lower for the frontal lobe (adjusted HR = 0.42), the basal ganglia (adjusted HR = 0.22), the radiation crown (adjusted HR = 0.42), the diencephalon (adjusted HR = 0.20), or multiple partial strokes (adjusted HR = 0.26), the risk of PSI after receiving acupuncture was lower. For all baseline complications, acupuncture reduced the risk of insomnia. The cumulative incidence of insomnia in the acupuncture cohort was significantly lower than the non-acupuncture cohort (log-rank test, P = 0.000).

Limitations: First, our research only included patients from a single center. Second, we did not classify the post-stroke insomnia severity. Second, the information was extracted manually. Overall, the sample size was small, and we needed to increase the sample size to strengthen the conclusions.

Conclusion: Acupuncture treatment reduced the risk of insomnia in stroke patients. Future research be conducted with increased sample sizes and further elaboration on the specific acupuncture protocols that were used.

Sleep disturbance predicts future health status after stroke

STUDY OBJECTIVES

We evaluated factors associated with the presence of sleep disturbance in patients with stroke and whether sleep disturbance predicted change in other patient-reported domains of health over time.

METHODS

Observational cohort study of 2,190 patients with stroke seen in a cerebrovascular clinic February 17, 2015 to July 5, 2017 who completed patient-reported outcome measures (PROMs) at ≥ 1 visit, including the Patient Health Questionnaire-9 depression screen, Quality of Life in Neurological Disorders (NeuroQoL) cognitive function and Patient-Reported Outcomes Information Measurement System (PROMIS) sleep disturbance, fatigue, anxiety, social role satisfaction, physical function, and pain interference. Separate multivariable models were constructed with PROMIS sleep disturbance as the dependent variable. Covariates included clinical and demographic variables, the Patient Health Questionnaire-9 depression screen scored on the PROMIS metric, and 1 of the 6 other PROMs. Among the 476 patients with ≥ 2 visits, linear regression models were constructed to determine the association of baseline sleep disturbance with follow-up PROMs after adjustment for the corresponding baseline PROMIS/NeuroQol scores, depression score, and clinical variables.

RESULTS

Younger age and all PROM scores were associated with sleep disturbance; depression had the greatest association among PROMs (beta estimate 0.53, 95% confidence interval, 0.49, 0.57), physical function had the least (-0.06, 95% confidence interval, -0.11, -0.01). Baseline PROMIS sleep disturbance score was associated with worse adjusted follow-up scores for depression, fatigue, social role satisfaction, and physical function.

CONCLUSIONS

Younger age and all 8 PROMs were associated with sleep disturbance in patients with stroke. The degree of sleep disturbance predicted future patient-reported outcomes for multiple domains of health. Further study is warranted to determine if interventions shown to improve sleep symptoms will also improve other outcomes.

Herbal medicine for post-stroke insomnia: A protocol for systematic review and meta-analysis

BACKGROUND

Post-stroke insomnia (PSI) is a highly prevalent complication in patients with stroke. However, there has been no comprehensive systematic review assessing the efficacy and safety of herbal medicine (HM) on PSI. This protocol was developed to conduct a systematic review and meta-analysis to evaluate the evidence related to the efficacy and safety of HM on PSI.

METHODS

We will perform a comprehensive electronic search, including Medline, EMBASE, CENTRAL, AMED, CINAHL, PsycARTICLES, and Chinese, Korean, and Japanese databases from their inception to November 2020. This systemic review will include only randomized controlled clinical trials of HM on PSI. The main outcome is the Pittsburgh Sleep Quality Index score. Two researchers will independently screen citations and abstracts, identify full-text articles for inclusion, extract data, and appraise the quality and risk of bias of included studies. A meta-analysis will be conducted using Review Manager 5.4. The evidence quality of each outcome will be appraised according to Grades of Recommendation, Assessment, Development, and Evaluation.

RESULTS

This protocol adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-P (PRISMA-P) guidelines to ensure clarity and completeness of reporting in all phases of the systematic review.

CONCLUSION

This study will provide evidence regarding the efficacy and safety of HM for the treatment of PSI.

ETHICS AND DISSEMINATION

No ethical approval will be needed because data from previously published studies in which informed consent was obtained by primary investigators will be retrieved and analyzed. We will publish this systematic review in a peer-reviewed journal.

OSF REGISTRATION DOI

10.17605/OSF.IO/PEHQZ.

Sleep Disorders in Stroke: An Update on Management

Stroke is a leading cause of disability and mortality all over the world. Due to an aging population, the incidence of stroke is rising significantly, which has led to devastating consequences for patients. In addition to traditional risk factors such as age, hypertension, hyperlipidemia, diabetes and atrial fibrillation, sleep disorders, as independent modifiable risk factors for stroke, have been highlighted increasingly. In this review, we provide an overview of common types of current sleep disturbances in cerebrovascular diseases, including insomnia, hypersomnia, breathing-related sleep disorders, and parasomnias. Moreover, evidence-based clinical therapeutic strategies and pitfalls of specific sleep disorders after stroke are discussed. We also review the neurobiological mechanisms of these treatments as well as their effects on stroke. Since depression after stroke is so prevalent and closely related to sleep disorders, treatments of post-stroke depression are also briefly mentioned in this review article.

Care of the Patient With Acute Ischemic Stroke (Posthyperacute and Prehospital Discharge): Update to 2009 Comprehensive Nursing Care Scientific Statement: A Scientific Statement From the American Heart Association

In 2009, the American Heart Association/American Stroke Association published a comprehensive scientific statement detailing the nursing care of the patient with an acute ischemic stroke through all phases of hospitalization. The purpose of this statement is to provide an update to the 2009 document by summarizing and incorporating current best practice evidence relevant to the provision of nursing and interprofessional care to patients with ischemic stroke and their families during the acute (posthyperacute phase) inpatient admission phase of recovery. Many of the nursing care elements are informed by nurse-led research to embed best practices in the provision and standard of care for patients with stroke. The writing group comprised members of the Stroke Nursing Committee of the Council on Cardiovascular and Stroke Nursing and the Stroke Council. A literature review was undertaken to examine the best practices in the care of the patient with acute ischemic stroke. The drafts were circulated and reviewed by all committee members. This statement provides a summary of best practices based on available evidence to guide nurses caring for adult patients with acute ischemic stroke in the hospital posthyperacute/intensive care unit. In many instances, however, knowledge gaps exist, demonstrating the need for continued nurse-led research on care of the patient with acute ischemic stroke.

Effect of early sleep apnoea treatment with adaptive servo-ventilation in acute stroke patients on cerebral lesion evolution and neurological outcomes: study protocol for a multicentre, randomized controlled, rater-blinded, clinical trial (eSATIS: early Sleep Apnoea Treatment in Stroke)

BACKGROUND

Sleep-disordered breathing (SDB) is highly prevalent in acute ischaemic stroke and is associated with worse functional outcome and increased risk of recurrence. Recent meta-analyses suggest the possibility of beneficial effects of nocturnal ventilatory treatments (continuous positive airway pressure (CPAP) or adaptive servo-ventilation (ASV)) in stroke patients with SDB. The evidence for a favourable effect of early SDB treatment in acute stroke patients remains, however, uncertain.

METHODS

eSATIS is an open-label, multicentre (6 centres in 4 countries), interventional, randomized controlled trial in patients with acute ischaemic stroke and significant SDB. Primary outcome of the study is the impact of immediate SDB treatment with non-invasive ASV on infarct progression measured with magnetic resonance imaging in the first 3 months after stroke. Secondary outcomes are the effects of immediate SDB treatment vs non-treatment on clinical outcome (independence in daily functioning, new cardio-/cerebrovascular events including death, cognition) and physiological parameters (blood pressure, endothelial functioning/arterial stiffness). After respiratory polygraphy in the first night after stroke, patients are classified as having significant SDB (apnoea-hypopnoea index (AHI) > 20/h) or no SDB (AHI < 5/h). Patients with significant SDB are randomized to treatment (ASV+ group) or no treatment (ASV- group) from the second night after stroke. In all patients, clinical, physiological and magnetic resonance imaging studies are performed between day 1 (visit 1) and days 4-7 (visit 4) and repeated at day 90 ± 7 (visit 6) after stroke.

DISCUSSION

The trial will give information on the feasibility and efficacy of ASV treatment in patients with acute stroke and SDB and allows assessing the impact of SDB on stroke outcome. Diagnosing and treating SDB during the acute phase of stroke is not yet current medical practice. Evidence in favour of ASV treatment from a randomized multicentre trial may lead to a change in stroke care and to improved outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02554487 , retrospectively registered on 16 September 2015 (actual study start date, 13 August 2015), and www.kofam.ch (SNCTP000001521).

Sleep impairment is related to health-related quality of life among caregivers of lower-functioning traumatic brain injury survivors

Objective: The purpose of this study was to examine perceived sleep-related impairment in caregivers of individuals with traumatic brain injury (TBI). Specifically, we examined the relationship between caregiver-perceived sleep-related impairment and different aspects of health-related quality of life (HRQOL) and explored whether these relationships were moderated by the perceived level of everyday function in the person with TBI. Method: Three hundred forty-one caregivers of individuals with TBI completed surveys to determine whether the association between sleep-related impairment and HRQOL was moderated by caregiver-perceived functional impairment of the person with injury. Participants completed measures from the Patient-Reported Outcomes Measurement Information System and the TBI-CareQOL. These measures were used to examine different aspects of HRQOL: caregiver-specific HRQOL, mental HRQOL, social HRQOL, and fatigue. The Mayo-Portland Adaptability Inventory-4 was used to measure caregiver perceptions of the level of everyday function in the person with injury. Results: Results indicated that caregiver-perceived sleep-related impairment was associated with each of the four HRQOL scores. This relationship was moderated by the caregiver-reported level of everyday function in the person with TBI for both caregiver-specific HRQOL and fatigue but not mental or social HRQOL. For caregiver-specific HRQOL and fatigue, caregiver-perceived sleep-related impairment was associated with worse HRQOL for those caring for individuals with lower perceived levels of everyday function, but not for those caring for individuals with higher levels of everyday function. Conclusions: Interventions to improve caregiver sleep and HRQOL should consider both psychosocial and environmental factors (i.e., factors related to the person with the TBI). (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Do emotional distress and functional problems in persons with traumatic brain injury contribute to perceived sleep-related impairment in caregivers?

OBJECTIVE

The goal of this study was to examine the association between characteristics of persons with traumatic brain injury (PwTBI) and perceived sleep-related impairment of the caregivers.

METHOD

Fifty-two dyads (n = 23 civilians, n = 29 service members/veterans [SMVs]) were enrolled. Caregivers completed the Patient-Reported Outcomes Measurement Information System Sleep-Related Impairment computer adaptive test, and PwTBI completed Quality of Life in Neurological Disorders measures of depression, anxiety, anger, cognitive functioning, and upper and lower extremity functioning. Hierarchical linear regression models, stratified by civilian/SMV group, were employed to assess prediction of caregiver-perceived sleep-related impairment from emotional distress of the PwTBI (anxiety, depressed mood, and anger) and perceived functional status of the PwTBI (cognitive, upper extremity, lower extremity functioning).

RESULTS

Compared with caregivers of civilians, caregivers of SMVs reported higher perceived sleep-related impairment. Regression results showed that characteristics of the PwTBI accounted for moderate amounts of variance in the sleep-related impairment of caregivers of both civilians and SMVs. Within-group analyses showed that the strongest predictor of sleep-related impairment of caregivers of civilians was self-reported cognitive function of the PwTBI (β = -0.82, p = .08); the strongest predictor of sleep-related impairment of caregivers of SMVs was self-reported anger of the PwTBI (β = 0.54, p = .07).

CONCLUSIONS

In both caregivers of civilians and SMVs with TBI, characteristics of the PwTBI were related to perceived caregiver sleep-related impairment. These preliminary data can inform future research with larger samples that examine the impact of multiple characteristics of the caregiver and care recipient on caregiver sleep. Findings highlight the potential importance of considering the dynamics of the dyad in rehabilitation programming not only for the PwTBI but for caregivers as well. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

ERS International Congress, Madrid, 2019: highlights from the Sleep and Clinical Physiology Assembly

The 2019 European Respiratory Society (ERS) International Congress took place in Madrid, Spain, and served as a platform to find out the latest advances in respiratory diseases research. The research aims are to understand the physiology and consequences of those diseases, as well as the improvement in their diagnoses, treatments and patient care. In particular, the scientific sessions arranged by ERS Assembly 4 provided novel insights into sleep-disordered breathing and new knowledge in respiratory physiology. This article, divided by session, will summarise the most relevant studies presented at the ERS International Congress. Each section has been written by Early Career Members specialising in the different fields of this interdisciplinary assembly.

The Instant Spontaneous Neuronal Activity Modulation of Transcutaneous Auricular Vagus Nerve Stimulation on Patients With Primary Insomnia

Primary insomnia (PI) is associated with increased spontaneous neuronal activity. Transcutaneous auricular vagus nerve stimulation (taVNS) modulates brain function, and it is an effective treatment for primary insomnia. However, whether taVNS alleviates insomnia through modulating spontaneous neuronal activity is not fully clarified. This study aims to investigate the instant effect of taVNS in modulating spontaneous neuronal activity in PI patients using resting-state functional magnetic resonance imaging (rs-fMRI). Twenty-two PI subjects underwent rs-fMRI scanning prior and immediately after 30 min treatment of taVNS controlled by twenty healthy adults. Amplitude of low frequency fluctuations (ALFF) analysis was employed to assess the difference in spontaneous neuronal activity between PI patients and healthy adults, as well as between pre-treatment and post-treatment of taVNS. The taVNS-induced altered ALFF brain areas were then selected as regions of interest to perform the resting state functional connectivity (RSFC) analysis in PI patients. The right precuneus showed significantly increased ALFF in PI patients. After immediate taVNS treatment, the ALFF was significantly decreased in the right precuneus and increased in the left middle occipital gyrus. The RSFC in right precuneus with right angular, right superior frontal gyrus, and right middle frontal gyrus was significantly decreased. This study provides insights into the instant brain effects of taVNS on PI patients.

Sleep-related symptoms in patients with mild stroke

STUDY OBJECTIVES

Treatable sleep-related conditions are frequent in stroke patients, although their prevalence across stroke types and ideal method for screening is not clear. The objectives of this study were to evaluate the prevalence of sleep disturbance across different stroke types and identify approaches to the collection of sleep-related measures in clinical practice.

METHODS

We performed an observational cohort study of 2,213 patients with ischemic stroke, intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), or transient ischemic attack seen in a cerebrovascular clinic February 17, 2015 through July 5, 2017 who completed at least one of the following sleep-related questionnaires: Patient-Reported Outcomes Measurement Information System (PROMIS) sleep disturbance, Insomnia Severity Index (ISI), Sleep Apnea Probability Scale (SAPS), and sleep duration. Prevalence of abnormal scores were calculated using the following thresholds: PROMIS sleep disturbance ≥ 55, ISI ≥ 15, SAPS score ≥ 0.50, and sleep duration fewer than 6 or more than 9 hours. Sensitivity, specificity, and positive and negative predictive values of PROMIS sleep disturbance T-score ≥ 55 to identify patients with moderate-severe insomnia (ISI ≥ 15) were computed.

RESULTS

In the cohort, 28.6% patients (624/2183) had PROMIS sleep disturbance score ≥ 55, 17.6% (142/808) had ISI ≥ 15, and 61.3% (761/1241) had a positive SAPS screen. The frequency of abnormal sleep scale scores was similar across time periods and stroke types. The sensitivity and specificity of PROMIS sleep disturbance T-score ≥ 55 to identify patients with ISI ≥ 15 were 0.89 (95% confidence interval 0.83-0.94) and 0.81 (95% confidence interval 0.78-0.84), respectively.

CONCLUSIONS

The prevalence of sleep-related symptoms in patients with mild stroke are similar across stroke types and time periods after stroke. Potential approaches to screening for sleep disturbance in stroke patients are provided.

The effect of uric acid on sleep quality after acute ischemic stroke

Sleep disturbance is a common psychiatric complication after stroke. Oxidative stress has been an important pathophysiological mechanism of sleep disturbance. However, no study has explored the relationship between uric acid (UA) and post-stroke sleep quality. This prospective study included 191 patients who were followed up for two months after acute ischemic stroke. Serum UA levels were measured at admission and divided into 3 tertiles (≤251 μmol/L, 252-326 μmol/L, ≥327 μmol/L). Patients in the 3rd tertile of UA levels had a lower incidence of poor sleep quality than those belonging to 2nd or 1st tertile, respectively (9.7% vs. 27.7% vs. 35.9%; P = 0.002). Furthermore, high UA levels (≥327 μmol/L) were independently associated with low risk of poor sleep quality (OR = 0.129, 95%CI = 0.031-0.528, P = 0.004) after adjusting for demographics, cardiovascular risk factors, stroke severity, functional outcome and depressive symptoms. High modified Rankin Scale score and depressive symptoms were associated with increased risk of poor sleep quality after stroke (OR = 1.836, 95%CI = 1.035-3.354, P = 0.038) and (OR = 5.082, 95%CI = 1.709-15.115, P = 0.003). In conclusion, high UA levels may reduce the risk of poor sleep quality after acute ischemic stroke. Further randomized controlled trials are necessary in examining whether appropriate UA supplement could provide a potential prevention or therapeutic target for sleep disturbance after stroke.

Diagnosis and management of central sleep apnea syndrome

Introduction: Central sleep apnea (CSA) syndrome has gained a considerable interest in the sleep field within the last 10 years. It is overrepresented in particular subpopulations such as patients with stroke or heart failure. Early detection and diagnosis, as well as appropriate treatment of central breathing disturbances during sleep remain challenging. Areas covered: Based on a systematic review of CSA in adults the clinical evidence and polysomnographic patterns useful for discerning central from obstructive events are discussed. Current therapeutic indications of CSA and perspectives are presented, according to the type of respiratory disturbances during sleep, alterations in blood gases and ventilatory control. Expert opinion: The precise identification of central events during polysomnographic recording is mandatory. Therapeutic choices for CSA depend on the typology of respiratory disturbances observed by polysomnography, changes in blood gases and ventilatory control. In CSA with normocapnia and ventilatory instability, adaptive servo-ventilation is recommended. In CSA with hypercapnia and/or rapid-eye movement sleep hypoventilation, non-invasive ventilation is required. Further studies are required as strong evidence is lacking regarding the long-term consequences of CSA and the long-term impact of current treatment strategies.

Risks associated with the stroke predisposition at young age: facts and hypotheses in light of individualized predictive and preventive approach

Stroke is one of the most devastating pathologies of the early twenty-first century demonstrating 1-month case-fatality rates ranging from 13 to 35% worldwide. Though the majority of cases do occur in individuals at an advanced age, a persistently increasing portion of the patient cohorts is affected early in life. Current studies provide alarming statistics for the incidence of "young" strokes including adolescents. Young stroke is a multifactorial disease involving genetic predisposition but also a number of modifiable factors, the synergic combination of which potentiates the risks. The article analyzes the prevalence and impacts of "traditional" risk factors such as sedentary lifestyle, smoking, abnormal alcohol consumption, drug abuse, overweight, hypertension, abnormal sleep patterns, and usage of hormonal contraceptives, among others. Further, less explored risks such as primary vascular dysregulation and associated symptoms characteristic for Flammer syndrome (FS) are considered, and the relevance of the FS phenotype for the stroke predisposition at young age is hypothesized. Considering the high prevalence of known genetic and modifiable risk factors in the overall predisposition to the young stroke, the risk mitigating measures are recommended including innovative screening programs by application of specialized questionnaires and biomarker panels as well as educational programs adapted to the target audiences such as children, adolescents, and young adults.