Sleep disorders and stroke

Sleep Apnea and Incident Stroke in a National Cohort of Black and White Adults

BACKGROUND AND OBJECTIVES

Racial/ethnic differences have been documented in the relationship between obstructive sleep apnea (OSA) and stroke incidence, yet racial differences in OSA symptoms or treatment and their relationship with stroke incidence are underexplored and may contribute to stroke disparities. We comprehensively examined OSA symptoms and their relationships to stroke incidence by race/ethnicity.

METHODS

Data were collected from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study, a population-based cohort of Black and White individuals in the United States. Participants free from a stroke diagnosis at baseline were included. Participants self-reported the following: (1) snoring; (2) daytime sleepiness; (3) provider-diagnosed sleep apnea (PDSA); and (4) treatment for PDSA using positive airway pressure (PAP). OSA risk was categorized as high or low based on the Berlin Sleep Questionnaire. Incident stroke was defined as first occurrence of stroke over an average of 12 (SD 3.9) years of follow-up. We report the relationships between snoring, OSA risk, PDSA, PAP therapy use, and incident stroke by race/ethnicity using Cox proportional hazards models after adjusting for demographic and socioeconomic factors and stroke risk factors.

RESULTS

Among the 22,192 participants (mean age [SD] 64.2[9.1] years), 38.1% identified as Black. Overall, snoring was not associated with incident stroke (hazard ratio [HR] 0.98, 95% CI 0.85-1.13). However, among White individuals but not Black individuals, high OSA risk and PDSA were associated with incident stroke (HR 1.22, 95% CI 1.01-1.47; HR 1.33, 95% CI 1.04-1.70, respectively). PAP therapy use among those with PDSA (compared with non-PDSA) was associated with incident stroke in White individuals (HR 1.38, 95% CI 1.05-1.80). PAP therapy use among those with PDSA (compared with those with PDSA without PAP therapy use) was associated with reduced risk of incident stroke in Black (HR 0.39, 95% CI 0.17-0.91) but not White (HR 0.63, 95% CI 0.37-1.10) individuals.

DISCUSSION

White individuals with high OSA risk and those with PDSA with or without PAP therapy use were at increased incident stroke risk, whereas Black individuals reporting PDSA and PAP had reduced incident stroke risk relative to those not using PAP. Future research is needed to understand the mechanisms underlying racial differences in OSA and stroke such as differences in assessment modes and treatment.

Correlation analysis of heart rate variations and glucose fluctuations during sleep

OBJECTIVE

The body's glucose concentration is influenced by carbohydrate intake, insulin-induced carbohydrate reduction, and hepatic glycogen breakdown induced by stress hormones. This study investigated the potential of employing glucose fluctuations as a measure of stress by examining the relationship between heart rate variability (HRV) data and glucose levels during sleep in healthy subjects.

METHODS

In this cross-sectional study, a chest-worn electrocardiogram (ECG) and continuous glucose monitoring device (CGM) were respectively used to monitor the heart rate intervals and glucose fluctuations of five subjects (two males, three females) during sleep. A time-series correlation analysis was performed on the HRV data extracted from heart rate intervals and the corresponding glucose fluctuation data.

RESULTS

The time-series analysis of ECG and CGM data collected from subjects during sleep (n = 25 nights) revealed a moderate negative correlation between glucose levels and HRV, with a cross-correlation coefficient of r = -0.453.

CONCLUSION

Similar to HRV, changes in stress levels can be detected by observing glucose fluctuations, particularly during sleep when the impact of food intake can be eliminated. Our findings highlight a significant correlation between glucose levels and HRV, indicating that glucose fluctuations can be used as an indicator of autonomic nervous system activity in an exploratory study.

Prevalence and determinants of post-stroke sleep disorders: a cross-sectional hospital-based study

INTRODUCTION

Post-stroke sleep disorders (PSSD) are an important part of post-stroke disability. PSSD is neglected as a part of stroke rehabilitation. We aimed to study the prevalence and determinants of PSSD in a hospital based, single center setting.

METHODS

In a cross-sectional study, adult patients (≥ 18 years) with stroke (one month to one year after the onset), were enrolled in the study. Demographic, clinical, radiological, and motor and functional disabilities were assessed. Sleep quality was assessed with Pittsburg Sleep Quality Index (PSQI) and STOP BANG questionnaire (for obstructive sleep apnea [OSA]). Patients with poor sleep quality (PSQI > 5) were analyzed for risk factors.

RESULTS

A total of 103 patients were recruited in the study period (January 2021 to June 2022). The self-reported prevalence of PSSD was 16% which increased to 72% when the PSQI was administered. High risk of OSA was present in 33%. In bivariate analysis, factors associated with PSQI > 5 were involvement of ≥ 2 lobes, lower body mass index (BMI), worse modified Rankin Scale (mRS), Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A) and Stroke Specific Quality of Life (SSQoL). In multivariate analysis, only depression was associated with PSQI > 5 (OR: 1.3 (1.0; 1.7); p-value = 0.03).

CONCLUSION

PSSD had a prevalence of 72%. In multivariate analysis, the factor associated with PSQI > 5 was worse HAM-D score.

Effects of Ischemic Stroke on Interstitial Fluid Clearance in Mouse Brain: a Bead Study

The clearance of brain interstitial fluid (ISF) is important in maintaining brain homeostasis. ISF clearance impairment leads to toxic material accumulation in the brain, and ischemic stroke could impair ISF clearance. The present study investigates ISF clearance under normal and ischemic conditions. The carboxylate-modified FluoSpheres beads (0.04 μm in diameter) were injected into the striatum. Sham or transient middle cerebral artery occlusion surgeries were performed on the mice. The brain sections were immunostained with cell markers, and bead distribution at various time points was examined with a confocal microscope. Primary mouse neuronal cultures were incubated with the beads to explore in vitro endocytosis.  Two physiological routes for ISF clearance were identified. The main one was to the lateral ventricle (LV) through the cleft between the striatum and the corpus callosum (CC)/external capsule (EC), where some beads were captured by the ependymal macrophages and choroid plexus. An alternative and minor route was to the subarachnoid space through the CC/EC and the cortex, where some of the beads were endocytosed by neurons. After ischemic stroke, a significant decrease in the main route and an increase in the minor route were observed. Additionally, microglia/macrophages engulfed the beads in the infarction. In conclusion, we report that the physiological clearance of ISF and beads mainly passes through the cleft between the CC/EC and striatum into the LV, or alternatively through the cortex into the subarachnoid space. Stroke delays the main route but enhances the minor route, and microglia/macrophages engulf the beads in the infarction. Ischemic stroke impairs the clearance of brain interstitial fluid/beads. Under physiological conditions, the main route ( ① ) of interstitial fluid clearance is to the lateral ventricle, and the minor one ( ② ) is to the subarachnoid space. Ischemic stroke weakens the main route ( ① ), enhances the minor one ( ② ), and leads to microglial/macrophage phagocytosis within the infarction ( ③ ).

Impact of site, size and severity of ischemic cerebrovascular stroke on sleep in a sample of Egyptian patients a polysomnographic study

BACKGROUND

Sleep difficulties following a cerebrovascular stroke are an interesting topic in the scientific community. Following a brain ischemic insult, a variety of sleep problems can occur.

AIM OF WORK

To study the sleep architecture following stroke and to identify the impact of site, size and severity of ischemic cerebrovascular troke on sleep microstructure.

SUBJECTS AND METHODS

this was a case control study; polysomnogram was done for 93 patients admitted to the stroke unit at El- Hadara university hospital with the first ever ischemic stroke. NIHSS was calculated immediately and 1 month after stroke onset. 50 age matched control subjects with no evidence of central nervous system or major psychiatric disorder by history or clinical examination.

RESULTS

Total sleep time, sleep efficiency were lower in ischemic cerebrovascular stroke patients than in control group and this was statistically significant (p = .001* p = .0001* respectively). Arousal index limb movement index and snoring index were all higher among the ischemic cerebrovascular stroke group in comparison to the control group and this was statistically significant (p = .0001*p = .05*p = .0001). Both the REM(rapid eye movement) and REM latency were highest among brain stem stroke, and this was statistically significant p = .043*, p = .0.001*.cortical infarcts showed higher AHI (apnea hypopnea index)and this was statistically significant p = 0.002* Limb movement index was higher among sizable size stroke and this was statistically significant (p = 0.038). NIHSS National Institutes of Health Stroke Scale after 1 month follow up showed a significant indirect correlation with the lowest oxygen saturation during sleep (p = 0.047). Lowest oxygen saturation was lowest among sizable stokes and desaturation index was highest among sizable size strokes both were statistically significant p = 0.006. NIHSS2 had a significant negative correlation with the lowest oxygen saturation during sleep p = 0.047.

CONCLUSION

The microstructure of sleep is significantly impacted by cerebrovascular stroke. Brain stem strokes had the highest REM and REM latency, while cortical strokes had the highest moderate-to-severe AHI. Sizable strokes displayed increased indices of limb movement, desaturation, and oxygen saturation.

Factors influencing recurrence after an ischemic stroke vary by sex

OBJECTIVES

To determine the factors that affect recurrent stroke after acute ischemic stroke, specifically between male and female groups.

METHODS

We examined relative factors associated with recurrent stroke in Chinese patients with first-ever ischemic stroke. LASSO (least absolute shrinkage and selection operator) Cox regression were used to determine the predictors of recurrent stroke in the male and female groups. Next, We used Kaplan-Meier survival curves and interactions among these predictors to assess the association between relapse-related factors and recurrent stroke.

RESULTS

During one year of follow-up, we documented 42 incidents of recurrent stroke in males and 15 in females. There was no significant difference in the overall recurrence rate between men and women. We finally identified three variables in males and one variable in females associated considerably with recurrent stroke by LASSO Cox regression. In females, good sleep appeared to be the most significant protective factor against recurrent stroke(hazard ratio [HR], 0.21; 95% CI, 0.08-0.57). In the male group, we found two risk factors: atherosclerotic burden (HR, 2.42; 95% CI, 1.30-4.51) and coronary heart disease (HR, 2.98; 95% CI, 1.16-7.66); and one protective factor: domestic/physical activities (HR, 0.45; 95% CI, 0.24-0.83). We also found an interaction between good sleep and domestic/physical activities in males (Pinteraction = 0.016).

DISCUSSION

Our data indicate that the factors for recurrent stroke may differ by sex. Engaging in domestic/physical activities may substantially lower recurrent strokes in Chinese adult males. And good sleep in females appears to be more important in preventing stroke recurrence.

Sleep disturbances and associated factors amongst stroke survivors in North Central, Nigeria

Introduction

Sleep disturbance is common in persons with stroke and when unrecognised and untreated may hinder rehabilitation efforts and lead to poor functional outcome. It may also result in increased risk for stroke recurrence.

Aim

We investigated the frequency and associated factors of sleep disturbances amongst stroke survivors.

Methodology

One hundred and ten stroke survivors attending the neurology outpatient clinics of two tertiary hospitals, from February 2021 to January 2022, were interviewed after obtaining ethical approval and informed consent. We used a structured questionnaire to obtain their socio-demographic, clinical characteristics and sleep disturbances. Excessive daytime sleepiness was assessed using the Epworth Sleepiness Scale (ESS). Data were analysed with statistical significance set at P < 0.05.

Results

Eighty (72.7%) patients were males with a mean age of 61.4 ± 11.8, slightly older than the females (30, 27.3%) with a mean age of 60.9 ± 2.9. Their median follow-up duration was 7.5 months. Majority (84, 76.4%) had ischaemic stroke, and the frequency of sleep disturbances was 37 (33.6%) consisting of insomnia (19, 17.3%), hypersomnia (10, 9.0%), sleep-disordered breathing (5, 4.5%) and sleep-related movement disorder (3, 2.7%), respectively. Using the ESS score, 22 (20.0%) had mild, 10 (9.0%) had moderate and 7 (6.4%) had severe ESS scores, respectively. Univariate analysis showed depression to be significantly associated with ESS (P = 0.006) whereas multivariate analysis revealed age and sex as significant associated factors (P = 0.008 and P = 0.009) of ESS.

Conclusion

More than one-third of participants reported sleep disturbances with depression, age and gender as associated factors.

Sleep Quality and Cognitive Function after Stroke: The Mediating Roles of Depression and Anxiety Symptoms

This study examined the association between post-stroke cognitive function and sleep status at 30 days post-stroke and evaluated the role of anxiety and depression as potential mediators of that association. The participants in this study were 530 acute ischemic stroke (IS) patients. Sleep disturbance at 30 days post-stroke was assessed by the Pittsburgh Sleep Quality Index. Basic patient information, cognitive function, depression, and anxiety status were assessed before discharge from the hospital. Stratified linear regression analysis models were fit to examine the associations between post-stroke sleep quality and the influencing factors. A structural equation model was developed to evaluate the role of anxiety and depression as potential mediators of sleep quality and cognitive function. At 30 days post-stroke, 58.7% of IS patients had sleep disturbance. Women and older IS patients were more likely to suffer poorer sleep quality (p < 0.05). A stratified linear regression analysis showed that the inclusion of cognitive function variables and indicators of depression and anxiety were statistically significant in predicting improvement in the sleep disturbance of AIS patients. Cognitive function, depression, anxiety, and sleep status were selected to construct a structural equation model. The total effect of cognitive function on sleep status was -0.274, with a direct effect of -0.097 and an indirect effect (through depression) of -0.177. The total effect of anxiety on sleep status was 0.235, with a direct effect of 0.186 and an indirect effect (through depression) of 0.049. IS patients often experience poor sleep quality. Depression in IS patients mediates two pathways: the pathway through which cognitive function affects sleep quality and the pathway through which anxiety affects sleep quality.

Association Between Traumatic Brain Injury and Increased Risk of Stroke: A Systematic Review and Meta-analysis

OBJECTIVE

To determine whether exposure to traumatic brain injury (TBI) is associated with increased risk of stroke in adults compared with referents not exposed to TBI, and to understand whether an association exists throughout the spectrum of injury severity, whether it differs between the acute and chronic phases after TBI, and whether the association is greater with hemorrhagic compared with ischemic stroke after TBI.

SETTING

A database search was conducted on January 22, 2021. Searches were run in MEDLINE (1946 to present), Embase (1988 to present), Evidence-Based Medicine Reviews (various dates), Scopus (1970 to present), and Web of Science (1975 to present).

DESIGN

Observational studies that quantified the association of stroke after TBI compared with referents without TBI were included. Three coauthors independently reviewed titles and abstracts to determine study eligibility. Study characteristics were extracted independently by 2 coauthors who followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and study quality was assessed independently by 2 coauthors who used the Newcastle-Ottawa Scale. Random-effects meta-analyses were performed.

MAIN MEASURES

The primary exposure was TBI of any severity, and the primary outcome was stroke of any kind. Subgroup analysis was performed to assess heterogeneity associated with severity of TBI, type of stroke, and time from TBI to stroke.

RESULTS

A total of 64 full-text articles were reviewed, and data were extracted from 8 cohort studies (N = 619 992 individuals exposed to TBI along with nonexposed referents). A significant overall association was found with TBI and stroke (hazard ratio, 2.06; 95% CI, 1.28-3.32). Significant subgroup differences were found with a smaller risk of ischemic stroke compared with stroke of all types (P < .001, I² = 93.9%).

CONCLUSIONS

TBI, regardless of injury severity, was associated with a higher risk of stroke. To improve secondary stroke prevention strategies, future studies should classify TBI severity and type of stroke more precisely and determine long-term risk.

Identification of salivary microRNA profiles in male mouse model of chronic sleep disorder

Chronic sleep disorders (CSD) comprise a potential risk factor for metabolic and cardiovascular diseases, obesity and stroke. Thus, the identification of biomarkers for CSD is an important step in the early prevention of metabolic dysfunctions induced by sleep dysfunction. Diagnostic saliva samples can be easily and noninvasively collected. Thus, we aimed to identify whole microRNA (miRNA) profiles of saliva in control and psychophysiologically stressed CSD mouse models and compare them at Zeitgeber time (ZT) 0 (lights on) and ZT12 (lights off). The findings of two-way ANOVA revealed that the expression of 342 and 109 salivary miRNAs was affected by CSD and the time of day, respectively. Interactions were found in 122 miRNAs among which, we identified 197 (ZT0) and 62 (ZT12) upregulated, and 40 (ZT0) and seven (ZT12) downregulated miRNAs in CSD mice. We showed that miR-30c-5p, which is elevated in the plasma of patients with hypersomnia, was upregulated in the saliva of CSD mice collected at ZT0. The miRNAs, miR-10a-5p, miR-146b-5p, miR-150-5p, and miR-25-3p are upregulated in the serum of humans with poor sleep quality, and these were also upregulated in the saliva of CSD mice collected at ZT0. The miRNAs miR-30c, miR146b-5p, miR150, and miR-25-5p are associated with cardiovascular diseases, and we found that plasma concentrations of brain natriuretic peptides were significantly increased in CSD mice. The present findings showed that salivary miRNA profiles could serve as useful biomarkers for predicting CSD.

Associations between the timing of different foods’ consumption with cardiovascular disease and all-cause mortality among adults with sleep disorders

Introduction

People with sleep disorders are under disrupted biological rhythms. Whether changing the timing of specific food consumption contributes to decreasing cardiovascular and all-cause risk is unknown.

Methods

A total of 8,005 participants with sleep disorders were selected from the U.S. National Health and Nutrition Examination Survey (NHANES) from 2005 to 2014. Cox proportional hazards regression models were used to analyze the relationship between the consumption time of foods and cardiovascular disease (CVD) and all-cause death. Moreover, equivalent food substitution models were carried out to evaluate the alterations in the risk of CVD mortality for the changed food intake time.

Results

After adjusting for multiple confounders, participants who consume red and orange vegetables, starchy vegetables, and fermented dairy in the morning (hazard ratio (HR)_{red and orange vegetables} = 0.45, 95% CI: 0.26–0.81; HR_{starchy vegetables} = 0.47, 95% CI: 0.25–0.88; HR_{fermented dairy} = 0.57, 95% CI: 0.36–0.89) and milk and eggs in the evening contribute to reducing the likelihood of death from CVD (HR_milk = 0.65, 95% CI: 0.43–0.96; HR_eggs = 0.72, 95% CI: 0.53–0.98). Iso-calorically switching 0.1 serving of starchy vegetable and fermented dairy and milk intake from one period to another does significantly reduce the mortality risk of CVD.

Conclusion

Higher intake of red and orange vegetables, starchy vegetables, and fermented dairy in the morning and milk and eggs in the evening confers a lower risk of CVD among individuals with sleep disorders.

Modulation of melatonin to the thalamic lesion-induced pain and comorbid sleep disturbance in the animal model of the central post-stroke hemorrhage

The devastating chronic central post stroke pain is associated with variety of comorbidities. Disrupted sleep is a severe comorbidity, causing an increase in the suicide rate, due to CPSP’s pain symptom. Melatonin is a well-known jet-lag compound, which helps in entrainment of sleep cycle. Accordingly, whether melatonin as a therapeutic measurement for the regulation of sleep disturbance related to central post stroke pain remains unclear. Exogenous melatonin administration entrained the disrupted 24 h circadian cycle, more effectively after 2 and 3 week of administration. The effect of melatonin was persisted on 4th week too, when melatonin administration was discontinued. Also, melatonin ameliorated the pain due to distorted sleep-activity behavior after melatonin administration for 3 weeks. The low levels of melatonin in blood plasma due to CPSP were restored after 3 weeks of melatonin administration. After 30 mg/kg melatonin administrations for 3 weeks, all the disrupted resting and activity behaviors were reduced during light and dark periods. The results suggested that melatonin significantly ameliorated CPSP’s pain symptoms and comorbid sleep disturbance showing in activity behavior.

Poor sleep quality, vitamin D deficiency and depression in the stroke population: A cohort study

BACKGROUND

Depression is a common psychiatric complication after stroke. However, the relationships among sleep quality, vitamin D status and depression are unclear in stroke patients. The aim of this study was to explore the impact of poor sleep quality and vitamin D status on post-stroke depression (PSD).

METHODS

In the present study, 233 stroke patients completed the one-month follow-up. Sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI) both at admission and 1 month after stroke. Depressive symptom was measured by the Hamilton Depression Scale (HAMD) at 1 month after stroke. Serum vitamin D levels were measured at admission. Multivariable logistic regression and mediation analysis were used to examine the mediating and moderating effects of sleep quality and vitamin D status on PSD.

RESULTS

The incidence of PSD was higher in patients with poor sleep quality than those with good sleep quality. Vitamin D levels were negatively correlated with HAMD score (r = -0.244, P < 0.001). Prestroke poor sleep quality was associated with an increased risk of PSD in the vitamin D deficiency group after adjustment for potential confounders (OR = 4.047, 95%CI = 1.300-12.600, P = 0.016), while this association was not significant in the vitamin D sufficiency group. In mediation analysis, the relationship between vitamin D deficiency and PSD was mediated by poststroke sleep quality.

LIMITATIONS

Vitamin D levels were measured only at admission.

CONCLUSIONS

The combination of poor sleep quality and vitamin D deficiency is associated with a substantially increased risk of PSD.

Circadian parameter as a possible indicator of gait performance and daily activity levels in chronic stroke survivors

Stroke recovery is a critical public health problem. It involves cognitive and physical impairments leading to physical inactivity. In addition, there are also sleep problems and disruption of the circadian rhythm. In this paper, we analyze the relation between cognitive impairments level, walking performance, sleep and circadian parameters of a group of chronic stroke survivors. Five stroke survivors enrolled in the study. The clinical assessments were: cognitive function (MoCA), the 10 meter-walking test (10MWT), and the 6 minutes walking test (6MWT). The circadian rhythm parameters were obtained for at least one week wearing the actimeters. There was a positive correlation between the duration of the main sleep episode and the MoCA scores. There were significant correlations between the 10MWT and 6MWT and the circadian parameters that were positive for most active period (M10), Interdaily stability (IS), Mesor and Amplitude and negative for intradaily variability (IV). Our results indicate that gait speed and resistance are correlated to circadian rhythm synchronization, lower rhythm variability and more defined activity-rest episodes. This preliminary study underscores the importance of including a continuous measure of sleep and activity cycles in the assessment of stroke survivors.

Sleep-wake disturbances in supra-and infratentorial stroke: an analysis of post-acute sleep architecture and apnea

BACKGROUND AND PURPOSE

Sleep-wake disturbances (SWD) are common following stroke, and often extend into the post-acute to chronic periods of recovery. Of particular interest to recovery is a reduction in rapid eye movement (REM) sleep, as we know REM sleep to be important for learning and memory. While there is a breadth of evidence linking SWD and stroke, much less work has been done to identify and determine if differences in sleep architecture and apnea severity are dependent on stroke infarct topographies.

METHODS

A retrospective chart review was conducted of 48 ischemic stroke patients having underwent a full, overnight polysomnography (PSG). All patients were over 30 days post-injury (post-acute) at the time of the PSG. Patients were divided into supra- and infratentorial infarct topography groups based on available medical and imaging records. In addition to sleep study record review, cognitive and outcome measures were examined.

RESULTS

Results showed that patients with infratentorial stroke had poorer sleep efficiency, decreased REM sleep, and higher apnea hypopnea index (AHI) than those with supratentorial injuries. Longer continuous REM periods were correlated with higher verbal learning/memory scores, higher levels of positive affect, and lower levels of emotional/behavioral dyscontrol. Neither age nor AHI were significantly correlated with the amount or duration of REM. Slow-wave sleep was significantly reduced across both injury topographies.

CONCLUSIONS

Infratentorial ischemic stroke patients display significant disruptions in sleep architecture and may require close monitoring for SWDs in the post-acute period to maximize outcome potential. REM sleep is particularly affected when compared to supratentorial ischemic stroke.

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.

Treatments for sleep disturbances in individuals with acquired brain injury: A systematic review

OBJECTIVE

To systematically review the evidence on the treatments of sleep disturbances in individuals with acquired brain injury.

DATA SOURCES

PubMed, Embase, Web of Science, and PsycINFO were searched from inception to January 2021.

REVIEW METHOD

Eligibility criteria were (1) participants with mild to severe acquired brain injury from traumatic brain injury and stroke (⩾three months post-injury), (2) individuals aged 16 years and older, (3) participants with self-reported sleep disturbances, (4) controlled group studies and single case (experimental) studies, and (5) interventions aimed at treatment of sleep disturbances. Two researchers independently identified relevant studies and assessed their study quality using the revised Cochrane assessment of bias tool (RoB 2.0) and the risk-of-bias in N-of-1 trials (RoBiNT) scale.

RESULTS

The search yielded 655 records; 11 studies met the inclusion criteria and were included, with a total of 227 participants (207 individuals with traumatic brain injury, 20 stroke patients). Two studies included pharmacological therapy, six studies examined the effects of cognitive behavioral therapy and three studies investigated alternative interventions such as acupuncture.

CONCLUSION

Although there was heterogeneity in the study quality of the included studies, their outcomes suggest that cognitive behavioral therapy is recommended as treatment of choice for improving sleep in individuals with acquired brain injury, especially for patients with mild to severe traumatic brain injury. Future research should examine the effects of cognitive behavioral therapy in more high-quality randomized controlled designs.

Social support and sleep quality in patients with stroke: The mediating roles of depression and anxiety symptoms

BACKGROUND

Research has demonstrated that higher social support is associated with better psychological health, quality of life, cognition, activities of daily living and social participation, but the relationship between social support and sleep quality remains unknown.

AIMS

This study aimed to assess the incidence of poor sleep quality, clarify the relationship between social support and sleep quality amongst stroke patients and determine whether anxiety and depression symptoms mediate this relationship.

METHODS

We conducted a quantitative, cross-sectional study involving 238 patients with stroke (median age of 61 [range 29-87] years, 68.1% male) recruited from a comprehensive tertiary care hospital between September 2019 and January 2020. A self-administered, structured questionnaire was used for the survey. The mediating effect of anxiety and depression symptoms was assessed using the bootstrap method via Model 4 (parallel mediation) of the SPSS PROCESS macro.

RESULTS

Results showed that the incidence of poor sleep quality amongst stroke patients was 65%. Mediation analysis showed that social support exerted significant direct effects on sleep quality, and anxiety and depression symptoms mediated the relationship between social support and sleep quality.

CONCLUSION

Measures should be taken to enhance social support to improve the sleep quality of stroke patients.

SUMMARY STATEMENT

What is already known about this topic? Patients with stroke have a high rate of sleep disorders, anxiety and depression symptoms. Anxiety and depression symptoms have a negative effect on sleep quality. Social support may be an effective intervention to reduce anxiety and depression symptoms and improve sleep quality amongst stroke patients. What this paper adds? The incidence of poor sleep was high amongst stroke patients. Social support had a direct positive effect on sleep quality. Anxiety and depression symptoms played multiple mediating roles in the relationship between social support and sleep quality. The implications of this paper: Our study adds to the existing literature by clarifying how social support impacts the sleep quality of stroke patients. We suggested improving the sleep quality of stroke patients through enhancing social support and reducing anxiety and depression symptoms, especially in patients with low levels of social support.

Bed Sensor Technology for Objective Sleep Monitoring Within the Clinical Rehabilitation Setting: Observational Feasibility Study

Background

Since adequate sleep is essential for optimal inpatient rehabilitation, there is an increased interest in sleep assessment. Unobtrusive, contactless, portable bed sensors show great potential for objective sleep analysis.

Objective

The aim of this study was to investigate the feasibility of a bed sensor for continuous sleep monitoring overnight in a clinical rehabilitation center.

Methods

Patients with incomplete spinal cord injury (iSCI) or stroke were monitored overnight for a 1-week period during their in-hospital rehabilitation using the Emfit QS bed sensor. Feasibility was examined based on missing measurement nights, coverage percentages, and missing periods of heart rate (HR) and respiratory rate (RR). Furthermore, descriptive data of sleep-related parameters (nocturnal HR, RR, movement activity, and bed exits) were reported.

Results

In total, 24 participants (12 iSCI, 12 stroke) were measured. Of the 132 nights, 5 (3.8%) missed sensor data due to Wi-Fi (2), slipping away (1), or unknown (2) errors. Coverage percentages of HR and RR were 97% and 93% for iSCI and 99% and 97% for stroke participants. Two-thirds of the missing HR and RR periods had a short duration of ≤120 seconds. Patients with an iSCI had an average nocturnal HR of 72 (SD 13) beats per minute (bpm), RR of 16 (SD 3) cycles per minute (cpm), and movement activity of 239 (SD 116) activity points, and had 86 reported and 84 recorded bed exits. Patients with a stroke had an average nocturnal HR of 61 (SD 8) bpm, RR of 15 (SD 1) cpm, and movement activity of 136 (SD 49) activity points, and 42 reported and 57 recorded bed exits. Patients with an iSCI had significantly higher nocturnal HR (t₁₈=−2.1, P=.04) and movement activity (t₁₈=−1.2, P=.02) compared to stroke patients. Furthermore, there was a difference between self-reported and recorded bed exits per night in 26% and 38% of the nights for iSCI and stroke patients, respectively.

Conclusions

It is feasible to implement the bed sensor for continuous sleep monitoring in the clinical rehabilitation setting. This study provides a good foundation for further bed sensor development addressing sleep types and sleep disorders to optimize care for rehabilitants.

Post-stroke sleep disturbances and rehabilitation outcomes: a prospective cohort study

BACKGROUND

Poor sleep is common after stroke, and data regarding its effect on rehabilitation outcomes are limited. Controversial evidence was found concerning the effect of sedatives on improving sleep quality in poor sleepers after stroke.

AIM

To assess the prevalence of poor sleep in post-stroke patients and its effect on rehabilitation outcomes.

METHOD

A total of 104 stroke patients from two major stroke rehabilitation units in Western Australia was enrolled. Sleep quality was assessed using the Pittsburgh Sleep Quality Indexes at baseline and after stroke. The main outcome measures were Functional Independence Measure (FIM) change and length of stay (LOS). Sedative use during this period was also recorded.

RESULTS

A total of 29.8% post-stroke patients suffered from poor sleep. There was no relationship between poor sleep and the stroke characteristics, such as severity, side and type, or demographics, such as age and gender. Poor sleep quality was inversely associated with rehabilitation outcomes measured by FIM (Rs. -0.317, P = 0.005). However, there was no significant association between sleep quality and LOS (P = 0.763). Sedatives were used in 18.2% of patients but had no impact on sleep quality or rehabilitation outcomes.

CONCLUSION

This research supported that poor sleep was frequent after stroke and had negative effects on rehabilitation outcomes. Use of sedatives was of limited benefit to improve sleep quality, and further studies are required to search for strategies to improve sleep problems after stroke.

Resilience as the Mediating Factor in the Relationship Between Sleep Disturbance and Post-stroke Depression of Stroke Patients in China: A Structural Equation Modeling Analysis

Background: Stroke patients may suffer from a variety of symptoms which can result in sleep disturbance and post-stroke depression (PSD). Whereas, resilience can alleviate sleep disturbance and help maintain well-being after stroke. Objective: The aim of this study is to explore whether resilience plays a mediating role in the relationship between sleep disturbance and PSD of stroke patients in China. Methods: A cross-sectional study with a multi-stage sampling was carried out in Liaoning Rehabilitation Center and the Third People's Hospital of Chongqing in China from May to September 2019. A total of 353 stroke patients were enrolled in this study. Structural equation model (SEM) was used to test the mediating effect of resilience on the relationship between sleep disturbance and PSD. Results: The prevalence of PSD of stroke patients was 34.56%. Sleep disturbance contributed most to the variance of PSD and had a significantly positive association with PSD among stroke patients (P < 0.01). Resilience was negatively associated with PSD, and acted as a mediator between sleep disturbance and PSD (a ^* b = 0.201, BCa 95% CI: 0.156~0.254). Conclusions: The prevalence of PSD was high among the Chinese stroke patients. Sleep disturbance was highly associated with PSD, resulting in the increased risk of PSD. Furthermore, resilience has a mediating effect on the relationship between sleep disturbance and PSD, and could reduce the negative effect of sleep disturbance on the development of PSD.

Detection of cytokine-induced sickness behavior after ischemic stroke by an optimized behavioral assessment battery

Stroke causes severe and long-lasting symptoms in patients. Besides focal deficits such as speech impairment and limb weakness, stroke also results in neuropsychiatric symptoms, including fatigue, anxiety, and depression, which are debilitating and often impair post-stroke rehabilitation. However, in experimental stroke research, the study of neuropsychiatric symptoms and their therapeutic targeting has so far been largely neglected, which can be mainly attributed to the lack of appropriate tools to investigate such deficits in mice. Here, we report that neuropsychiatric symptoms can be differentiated from focal deficits and specifically modulated independent of treating the primary lesion. In order to achieve this, we developed a novel behavior analysis tool by assessing test performance of various tests, combining outcome parameters to cover functional domains of focal and neuropsychiatric symptoms, and finally weighted results into a time point-specific score. This weighted score enabled us to clearly differentiate focal deficits and neuropsychiatric symptoms and detect these until the chronic phase after stroke. Using this analysis tool, we detected that neutralizing systemic cytokines (TNF-α, IL-1β and IL-6) specifically ameliorated neuropsychiatric symptoms but did not affect focal deficits or lesion volume. Hence, most conventional studies analyzing only focal deficits and lesion volume as primary outcome measures would have missed these significant and translationally relevant therapeutic effects. We anticipate that these findings will encourage more detailed analyses of neuropsychiatric symptoms particularly for anti-inflammatory therapies in stroke and that the presented weighted composite score will facilitate this development.

Dysregulation of the orexin/hypocretin system is not limited to narcolepsy but has far-reaching implications for neurological disorders

Neuropeptides orexin A and B (OX-A/B, also called hypocretin 1 and 2) are released selectively by a population of neurons which projects widely into the entire central nervous system but is localized in a restricted area of the tuberal region of the hypothalamus, caudal to the paraventricular nucleus. The OX system prominently targets brain structures involved in the regulation of wake-sleep state switching, and also orchestrates multiple physiological functions. The degeneration and dysregulation of the OX system promotes narcoleptic phenotypes both in humans and animals. Hence, this review begins with the already proven involvement of OX in narcolepsy, but it mainly discusses the new pre-clinical and clinical insights of the role of OX in three major neurological disorders characterized by sleep impairment which have been recently associated with OX dysfunction, such as Alzheimer's disease, stroke and Prader Willi syndrome, and have been emerged over the past 10 years to be strongly associated with the OX dysfunction and should be more considered in the future. In the light of the impairment of the OX system in these neurological disorders, it is conceivable to speculate that the integrity of the OX system is necessary for a healthy functioning body.

Serum Kynurenines Correlate With Depressive Symptoms and Disability in Poststroke Patients: A Cross-sectional Study

Background

Poststroke depression (PSD) is related to adverse functional and cognitive prognosis in stroke patients. The participation of kynurenine pathway metabolites in depression has been previously proposed; however, there are few studies on its role in PSD and disability in stroke.

Objective

To investigate if there is a correlation between serum kynurenines levels with poststroke anxiety and depression symptoms and disability scales.

Methods

A cross-sectional case-control study was conducted in patients with first stroke, of >1 month and <1 year of evolution, with no history of previous psychiatric or neurological disorders; the Hospital Anxiety and Depression Scale (HADS), Montreal Cognitive Assessment (MoCA), functional evaluations (Barthel index, Functional Independence Measure [FIM]) were applied and serum kynurenines (Kyns) were determined.

Results

Sixty patients were included; significant depressive symptoms were found in 63% of the cases; a significant and positive correlation was obtained between levels of 3-hydroxykynurenine (3-HK) with HADS-T ( r = 0.30, P = .025) and HADS-D ( r = 0.28, P = .039). Depressed patients showed significantly higher levels of 3HK ( P = .048) and KYNA ( P = .0271) than nondepressed patients; the 3HK levels were inversely correlated with functional scales: Barthel index ( r = −0.31, P = .02), FIM ( r = −0.40, P = .01); in addition, serum 3HK levels were significantly higher in patients with poor sleep quality ( P = .0190).

Conclusions

Serum Kyns show correlation with the presence and severity of depressive symptoms and with the disability and sleep quality. Kyns may be a potential marker of depression risk and disability in stroke in future.

Is there an association among sleep duration, nap, and stroke? Findings from the China Health and Retirement Longitudinal Study

PURPOSE

The objective of this study was to assess the association among nighttime sleep, daytime napping, total sleep duration (nighttime sleep plus daytime napping), and stroke in an elderly Chinese population.

METHODS

Data were derived from the 2011 China Health and Retirement Longitudinal Study (CHARLS) with 4785 Chinese respondents over 65 years old. Four binary logistic regression models were used to estimate odds ratios and 95% confidence intervals of the association among total sleep duration, nighttime sleep, daytime napping, and stroke, adjusting for confounders.

RESULTS

After controlling for sociodemographic characteristics, lifestyle, health status, and comorbidity, there was no association between abnormal nighttime sleep and stroke (P values > 0.05). Compared to individuals with normal total sleep duration (7-8 h per day), short sleep duration (< 7 h per day) was approximately two times more likely to increase the risk of stroke (AOR = 1.81, 95%CI 1.10-2.97). Individuals who reported vision impairment, disability, hypertension, dyslipidemia, and mental health issues were at higher risk of stroke. In addition, physical activities with different levels were associated with a lower risk of stroke. Taking naps was not associated with stroke incidence (AOR = 1.12, 95%CI 0.77-1.64).

CONCLUSION

In this elderly Chinese population, short total sleep duration per 24 h, not merely daytime napping or nighttime sleep, was significantly associated with an increased risk of stroke. Preventive measures for stroke may require a focus on elderly, sedentary individuals who report other health problems.

Pre-stroke sleep duration and post-stroke depression

OBJECTIVE

Sleep disturbance and depression are common in stroke patients, however, little is known about the role of sleep in post-stroke depression. This study examined the association between pre-stroke sleep duration and depression at 90 days post-stroke in a population-based bi-ethnic sample.

METHODS

The study included 1369 stroke patients from the Brain Attack Surveillance in Corpus Christi project who survived 90 days post-stroke. Depression at 90 days post-stroke was assessed by the 8-item Patient Health Questionnaire, and pre-stroke sleep duration was self-reported shortly after stroke in reference to the pre-stroke state. Multiple imputation and inverse probability weighting were used to deal with missing data and attrition. Weighted logistic regression models were fit to examine the association between pre-stroke sleep duration and post-stroke depression.

RESULTS

The mean age was 68.2 years, and 63.6% were Mexican American. The prevalence of post-stroke depression was highest among participants reporting less than 6 hours of sleep before stroke (52.4%, 95% confidence interval = 45.7%-59.0%). Compared with participants reporting 7-8 hours of sleep before stroke, those with short sleep duration had significantly increased odds for post-stroke depression (odds ratio = 1.96; 95% confidence interval = 1.38-2.79), after adjustment for sociodemographic, stroke and pre-stroke characteristics including pre-stroke depression.

CONCLUSIONS

Pre-stroke short sleep duration may be an independent risk factor for post-stroke depression.

Validating the Adolescent Sleep Wake Scale for use with young adults

OBJECTIVE

There is a need for examination of sleep across the entire adolescence to young adulthood developmental period (AYA; ages 12-25 years). The Adolescent Sleep Wake Scale (ASWS) is a 28-item measure of overall subjective sleep quality, including five sleep behavior domains (difficulty going to bed, falling asleep, maintaining sleep, reinitiating sleep, and returning to wakefulness), and has been validated to assess overall sleep quality and insomnia symptoms in adolescents (12-18 years). The current study aimed to examine whether the ASWS could be used to assess sleep across the AYA period by investigating the validity of the measure in a national sample of young adults (ages 19-25) using validated adult sleep measures.

MATERIALS AND METHODS

A national sample recruited through Amazon's MTurk (N = 332; Mean age = 23.37 (SD = 1.55); 53.8% female; 51.4% Caucasian) completed an online survey including the ASWS, the Pittsburgh Sleep Quality Index (PSQI) and the Insomnia Severity Index (ISI). Bivariate correlational analyses were performed to explore convergent and discriminant validity.

RESULTS

The ASWS total score was strongly correlated with both the PSQI total score (r = -0.68) and ISI (r = -0.71) total score. The subscales of the PSQI, including Sleep Latency, Sleep Disturbance, and Daytime Dysfunction were correlated with corresponding ASWS domains. There were weak correlations with other subscales. Internal consistency was good (α = 0.88).

CONCLUSIONS

Our results suggest that the ASWS measures areas of sleep problems in a manner consistent with the most frequently utilized self-report assessment in adults and supports the use of the ASWS across AYA.

Effects of Comorbid Sleep Disorders on Cardiovascular Complications of Hypertension Among Patients With Newly-diagnosed Hypertension: An Analysis of the Korean National Health Insurance Service-National Sample Cohort

Objectives

This study investigated the effects of comorbid sleep disorders (SD) on the incidence of cardiovascular complications among newly-diagnosed hypertension (HTN) patients.

Methods

As study population, 124 057 newly-diagnosed essential HTN patients aged 30 or older, without cardiovascular complications at diagnosis with HTN, were selected from the National Health Insurance Service-National Sample Cohort. The incidence of cardiovascular complications was calculated, Cox proportional-hazards regression model was used to analyze the risk of complications, and the population attributable fraction (PAF) for cardiovascular complications of having comorbid SD at HTN diagnosis was calculated.

Results

Over 10 years, 32 275 patients (26.0%) developed cardiovascular complications. In HTN patients with comorbid SD at diagnosis of HTN, the incidence of cardiovascular complications (78.3/1000 person-years; 95% confidence interval [CI], 75.8 to 80.9) was higher than in those without comorbid SD (58.6/1000 person-years; 95% CI, 57.9 to 59.3) and the risk of cardiovascular complications was 1.21 times higher (95% CI, 1.17 to 1.25), adjusting for age, gender, income, area of residence, and comorbid diabetes mellitus. The PAF of having comorbid SD at diagnosis of HTN for the incidence of cardiovascular complications was 2.07% (95% CI, 1.69 to 2.44).

Conclusions

Newly-diagnosed essential HTN patients aged 30 or older who had comorbid SD at the time of their HTN diagnosis had a higher incidence of cardiovascular complications than those without comorbid SD. Age, gender, income, area of residence, and comorbid diabetes mellitus had a significant effect on the incidence of cardiovascular complications. Approximately 2% of cardiovascular complications were found to occur due to the presence of SD.

Risk Factors for Stroke Based on the National Health and Nutrition Examination Survey

OBJECTIVES

To explore the risk factors for stroke by using National Health and Nutrition Examination Survey (NHANES).

METHODS

A total of 19384 cases from the NHANES database during 2005 to 2016 were included in this study, of which 661 were stroke patients, with a weighted prevalence of 2.60%. Univariate and multivariate logistic regression analysis was used to analyze possible risk factors for stroke.

RESULTS

The risk of stroke was 1.839 times higher in subjects with diabetes than in those without diabetes, P<0.001. An average increase of 1 ug/dL in blood lead was associated with a 1.082-fold increase in stroke risk, P<0.001. Subjects with mild-, moderate-, and moderately severe or severe depression had a 1.567-fold, 1.836-fold, and 3.279-fold higher risk than those without depression respectively, P<0.001. The risk of stroke in subjects with sleep disorders was 1.622 times higher than those without sleep disorders, P<0.001.

CONCLUSIONS

Patients with diabetes, lower household income (<$2000), PHQ-9 depression score (5-27), trouble sleep, older age and higher concentration of blood lead are associated with a higher risk of stroke.

Association of diagnosed obstructive sleep apnea with kidney transplant outcomes

Obstructive sleep apnea (OSA) is common but underdiagnosed among patients with kidney disease. This study examines whether the diagnosis of OSA in kidney transplant recipients (KTR) affected death, death-censored graft failure (DCGF), and acute rejection (AR). We analyzed the records of KTR who underwent transplant between 2000 and 2015. A total of 4014 kidney transplants were performed during the study period. Of these, 415 (10.3%) had a diagnosis of pretransplant OSA. Pretransplant OSA was associated with a higher risk of death in unadjusted analyses. After adjustment for potential confounders, pretransplant OSA was not associated with risk of death (HR = 1.04, 95% CI: 0.80-1.36). Similarly, pretransplant OSA was associated with a slightly higher incidence of DCGF or AR but neither associations were significant (HR: 1.23, 95% CI: 0.85-1.47 for DCGF; HR 1.10, 95% CI: 0.90-1.36 for AR). A total of 117 (3.3%) were diagnosed with de novo OSA after transplant. Similar to the pretransplant OSA, unadjusted HR for death was significantly higher in the de novo OSA group (HR: 1.48, 95% CI: 1.19-1.84); however, after adjustment, de novo OSA was not significantly associated with risk of death (HR: 1.15, 95% CI: 0.92-1.45). Similarly, DCGF and AR rates were not significantly associated with de novo OSA (HR: 1.10, 95% CI: 0.84-1.44 for DCGF; HR 1.10, 95% CI: 0.90-1.33 for AR). Our work did not detect significant associations between OSA and risk of death, graft failure, and rejection but the estimates might be underestimated due to underdiagnosis of OSA.

Circadian activity rhythm and fragmentation are associated with sleep-wake patterns and sleep quality in patients with stroke

BACKGROUND

Activity levels and disturbances of the sleep-wake pattern affect health and quality of life and need to be further explored in patients with stroke.

OBJECTIVE

To evaluate activity levels and their association with sleep-wake patterns in patients with stroke.

METHODS

Ten adults with (51±6 years) and 10 without stroke (52±7 years) participated in the study; they were matched on age, sex and educational level. Neurological status, motor function, sleep quality, and activity levels were measured. The groups were compared using Student t-tests and the association between the measures was assessed using Pearson's correlation.

RESULTS

Compared to people without stroke, those with stroke had worse sleep quality (p = 0.044), twice lower 24h-activity levels (p < 0.0001), higher interdaily stability and intradaily variability, lower activity during the most active 10 h and during the least active 5 h. Sleep quality was associated with activity level (r= -0.72) and with within-day activity variability (r= 0.53).

CONCLUSIONS

Activity level and fragmentation are associated with sleep-wake patterns and sleep quality in patients with stroke.

Diurnal Cortisol Dynamics, Perceived Stress, and Language Production in Aphasia

Purpose The current study investigated diurnal cortisol dynamics in adults with and without aphasia, along with subjective reports of stress and measures of language production. Dysregulation of cortisol, a common biomarker of stress, is associated with cognitive dysfunction in different clinical populations. However, little is known about the consequences of stress-induced cortisol disturbances for stroke survivors, including those with aphasia. Method Nineteen participants with aphasia and 14 age-matched neurotypical adults were tested. Saliva samples were collected from participants to assess the cortisol awakening response, a marker of the integrity of the hypothalamic-pituitary-adrenal (HPA) axis. Participants also completed 2 subjective stress questionnaires. Language was evaluated using 3 short, picture description narratives, analyzed for discourse (dys)fluency and productivity markers. Results In contrast to neurotypical participants, adults with aphasia did not show the predictable cortisol awakening response. Participants with aphasia also showed an unusual heightened level of cortisol upon awakening. Additionally, neurotypical participants demonstrated an association between intact language performance and the cortisol awakening response, whereas the participants with aphasia did not, although they did perceive the language tasks as stressful. Conclusion This study indicates that the functionality of the HPA axis, as indexed by cortisol, contributes to optimal language performance in healthy adults. The absence of an awakening response among participants with aphasia suggests that stroke leads to dysregulation of the HPA axis, although the degree to which this impairment affects language deficits in this population requires further investigation.

Association between weekend catch-up sleep and health-related quality of life of Korean adults

Sleep debt is known to have harmful effects on health. Weekend catch-up sleep (CUS) is a behavior to cope with weekday sleep debt. However, it is unclear whether weekend CUS has advantageous effects on health because sleep hygiene guidelines recommend regularizing bed time and arousal time. The aim of this study was to identify whether weekend CUS behavior has an association with better health-related quality of life (HRQoL)According to the inclusion criteria, 4871 participants were selected from the 2016 Korea National Health and Nutrition Examination Survey. Sleep questionnaires and European quality of life scale-5 dimensions (EQ-5D) questionnaire were used to collect data about the participants' sleep patterns and HRQoL. Odds ratios (ORs) with 95% confidence intervals (95% CIs) for each dimensional problem of EQ-5D were derived by logistic regression. Mean EQ-5D index scores were compared between weekend CUS and non-CUS groups based on their weekday sleep durations and quintile of chronotype.The ORs of dimensional problems of HRQoL of non-CUS group versus weekend CUS group were 1.63 (95% CI 1.07, 2.47) for usual activities, and 1.45 (95% CI 1.11, 1.90) for anxiety/depression. Mean EQ-5D scores of the weekend CUS group were significantly higher than those of the non-CUS group for sleeping less than 6 hours (0.953 ± 0.004 vs 0.936 ± 0.007, P = .036) and sleeping 6 to 7 hours (0.965 ± 0.003 vs 0.955 ± .0.004, P = .045). These findings were similar in the fourth quintile (Q4) of chronotype (0.965 ± 0.007 vs 0.951 ± 0.008, P = .008) and fifth quintile (Q5) (0.952 ± 0.006 vs 0.941 ± 0.007, P = .022).Weekend CUS behavior was associated with better HRQoL than non-CUS among Korean adults. Especially, it was significant in participants who slept for less than 7 hours or participants whose chronotype was the fourth or fifth quintile. Attention may be needed for subjects with sleep short time and later chronotype who do not have weekend-CUS behaviors, because there is a risk that their HRQoL might be compromised.

Cerebral Hemodynamics in Sleep Apnea and Actigraphy-Determined Sleep Duration in a Sample of the Hispanic Community Health Study/ Study of Latinos

STUDY OBJECTIVES

We sought to evaluate cerebral hemodynamics in obstructive sleep apnea (OSA) and actigraphy-defined short sleep duration using transcranial Doppler ultrasound (TCD) blood flow velocity in a subsample of Hispanics/Latinos without stroke and cardiovascular disease.

METHODS

The sample consisted of consecutive participants at the Miami site of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) with overnight home sleep testing and 7 days of wrist actigraphy in the Sueño sleep ancillary study. Ninety-five participants had sleep data and TCD determined cerebral hemodynamics. We evaluated the association between OSA (apnea-hypopnea index [AHI] ≥ 5 events/h) and short sleep duration (< 6.8 hours; sample median) with cerebral blood flow velocities (CBFV) and pulsatility index (PI) for the middle cerebral (MCA) and basilar arteries (BA).

RESULTS

Median age was 48 years (range 20-64) with 71% females. Twenty-eight percent of the sample had OSA (AHI ≥ 5 events/h) with median AHI of 10.0 (range 5.0-51.7) events/h. In unadjusted analyses, participants with OSA had lower median CBFV in the BA (30.5 cm/s [interquartile range:10.2] versus 39.4 cm/s [13.3] P < .05), but not the MCA, whereas short sleepers had higher median vascular resistance in the MCA (PI = 0.92 [0.18] versus 0.86 [0.14] P < .05) and BA (PI = 1.0 [0.17] versus 0.93 [0.24] P < .05). After full adjustment, OSA was associated with decreased CBFV (β [SE] = -5.1 [2.5] P < .05) in the BA. Short sleep was associated with increased PI (β [SE] = 0.05 [0.02] P < .05) in the MCA.

CONCLUSIONS

In this sample of Hispanic/Latinos, OSA was associated with decreased daytime blood flow velocity in the BA, whereas actigraphy-defined short sleep duration was associated with increased cerebrovascular pulsatility in the MCA.

Characterization of the microvascular cerebral blood flow response to obstructive apneic events during night sleep

Obstructive apnea causes periodic changes in cerebral and systemic hemodynamics, which may contribute to the increased risk of cerebrovascular disease of patients with obstructive sleep apnea (OSA) syndrome. The improved understanding of the consequences of an apneic event on the brain perfusion may improve our knowledge of these consequences and then allow for the development of preventive strategies. Our aim was to characterize the typical microvascular, cortical cerebral blood flow (CBF) changes in an OSA population during an apneic event. Sixteen patients (age 58 ± 8    years , 75% male) with a high risk of severe OSA were measured with a polysomnography device and with diffuse correlation spectroscopy (DCS) during one night of sleep with 1365 obstructive apneic events detected. All patients were later confirmed to suffer from severe OSA syndrome with a mean of 83 ± 15 apneas and hypopneas per hour. DCS has been shown to be able to characterize the microvascular CBF response to each event with a sufficient contrast-to-noise ratio to reveal its dynamics. It has also revealed that an apnea causes a peak increase of microvascular CBF ( 30 ± 17 % ) at the end of the event followed by a drop ( - 20 ± 12 % ) similar to what was observed in macrovascular CBF velocity of the middle cerebral artery. This study paves the way for the utilization of DCS for further studies on these populations.

No association of moon phase with stroke occurrence

Stroke occurrence shows strong correlations with sleep disorders and even subtle sleep disturbances have been shown to affect ischemic stroke (IS) occurrence. Chronobiology also exerts effects, like the morning surge in IS occurrence. Lunar cycles have also been shown to affect sleep and other physiological processes, but studies on moon phases and its possible association with occurrence of stroke are rare and nonconclusive. Therefore, we studied the effects of moon phases on stroke hospitalizations and in-hospital mortality nationwide in Finland in 2004-2014. All patients aged ≥18 years with IS or intracerebral hemorrhage (ICH) as primary discharge diagnosis were included. Daily number of admissions was treated as a response variable while moon phase, year and astronomical season were independent variables in Poisson regression modeling. We found no association between moon phases and stroke occurrence. The overall occurrence rates did not vary between different moon phases for IS or ICH (p = 0.61 or higher). There were no differences between moon phases in daily admission rates among men, women, young and old patients for any of the stroke subtypes. There was no difference in in-hospital mortality with regard to moon phase for IS or ICH overall (p = 0.19 or higher), nor in subgroup analyses. There were no significant interactions between moon phase and astronomical season for stroke occurrence or in-hospital mortality. To conclude, in this over a decade-long nationwide study including a total of 46 million person years of follow-up, we found no association between moon phases and occurrence or in-hospital mortality rates of IS or intracerebral hemorrhage.

Development of an Algorithm to Identify Patients with Physician-Documented Insomnia

We developed an insomnia classification algorithm by interrogating an electronic medical records (EMR) database of 314,292 patients. The patients received care at Massachusetts General Hospital (MGH), Brigham and Women’s Hospital (BWH), or both, between 1992 and 2010. Our algorithm combined structured variables (such as International Classification of Diseases 9th Revision [ICD-9] codes, prescriptions, laboratory observations) and unstructured variables (such as text mentions of sleep and psychiatric disorders in clinical narrative notes). The highest classification performance of our algorithm was achieved when it included a combination of structured variables (billing codes for insomnia, common psychiatric conditions, and joint disorders) and unstructured variables (sleep disorders and psychiatric disorders). Our algorithm had superior performance in identifying insomnia patients compared to billing codes alone (area under the receiver operating characteristic curve [AUROC] = 0.83 vs. 0.55 with 95% confidence intervals [CI] of 0.76–0.90 and 0.51–0.58, respectively). When applied to the 314,292-patient population, our algorithm classified 36,810 of the patients with insomnia, of which less than 17% had a billing code for insomnia. In conclusion, an insomnia classification algorithm that incorporates clinical notes is superior to one based solely on billing codes. Compared to traditional methods, our study demonstrates that a classification algorithm that incorporates physician notes can more accurately, comprehensively, and quickly identify large cohorts of insomnia patients.

Obstructive Sleep Apnea Phenotypes and Markers of Vascular Disease: A Review

Obstructive sleep apnea (OSA) is a chronic and heterogeneous disorder that leads to early mortality, stroke, and cardiovascular disease (CVD). OSA is defined by the apnea–hypopnea index, which is an index of OSA severity that combines apneas (pauses in breathing) and hypopneas (partial obstructions in breathing) associated with hypoxemia. Yet, other sleep metrics (i.e., oxygen nadir, arousal frequency), along with clinical symptoms and molecular markers could be better predictors of stroke and CVD outcomes in OSA. The recent focus on personalized medical care introduces the possibility of a unique approach to the treatment of OSA based on its phenotypes, defined by pathophysiological mechanisms and/or clinical presentation. We summarized what is known about OSA and its phenotypes, and review the literature on factors or intermediate markers that could increase stroke risk and CVD in patients with OSA. The OSA phenotypes where divided across three different domains (1) clinical symptoms (i.e., daytime sleepiness), (2) genetic/molecular markers, and (3) experimental data-driven approach (e.g., cluster analysis). Finally, we further highlight gaps in the literature framing a research agenda.

Incidence, Characterization, and Predictors of Sleep Apnea in Consecutive Brain Injury Rehabilitation Admissions

OBJECTIVE

To prospectively examine the incidence and risk factors for sleep apnea in consecutive brain injury rehabilitation admissions.

SETTING

Inpatient neurorehabilitation hospital.

PARTICIPANTS

Participants (n = 86) were consecutive neurorehabilitation admissions.

DESIGN

Retrospective analysis of prospectively collected data.

MAIN MEASURES

Polysomnography.

RESULTS

Half (49%) of the sample was diagnosed with sleep apnea. For the full sample, univariate logistic regression revealed age (odds ratio: 1.08; 95% confidence interval: 1.04-1.11) and hypertension (odds ratio: 7.77; 95% confidence interval: 2.81-21.47) as significant predictors of sleep apnea diagnosis. Results of logistic regression conducted within the traumatic brain injury group revealed age (odds ratio: 1.07; 95% confidence interval: 1.02-1.13) as the only significant predictor of apnea diagnosis after adjustment for other variables. Hierarchical generalized linear regression models for the prediction of apnea severity (ie, apnea-hypopnea index found that Functional Independence Measure Cognition Score (P = .01) and age (P < .01) were significant predictors. Following adjustment for all other terms, only age (P < .01) remained significant.

CONCLUSION

Sleep apnea is prevalent in acute neurorehabilitation admissions and traditional risk profiles for sleep apnea may not effectively screen for the disorder. Given the progressive nature of obstructive sleep apnea and morbidity associated with even mild obstructive sleep apnea, early identification and intervention may address comorbidities influencing acute and long-term outcome.

Nonnegative matrix factorization and sparse representation for the automated detection of periodic limb movements in sleep

Stroke is a leading cause of death and disability in adults, and incurs a significant economic burden to society. Periodic limb movements (PLMs) in sleep are repetitive movements involving the great toe, ankle, and hip. Evolving evidence suggests that PLMs may be associated with high blood pressure and stroke, but this relationship remains underexplored. Several issues limit the study of PLMs including the need to manually score them, which is time-consuming and costly. For this reason, we developed a novel automated method for nocturnal PLM detection, which was shown to be correlated with (a) the manually scored PLM index on polysomnography, and (b) white matter hyperintensities on brain imaging, which have been demonstrated to be associated with PLMs. Our proposed algorithm consists of three main stages: (1) representing the signal in the time-frequency plane using time-frequency matrices (TFM), (2) applying K-nonnegative matrix factorization technique to decompose the TFM matrix into its significant components, and (3) applying kernel sparse representation for classification (KSRC) to the decomposed signal. Our approach was applied to a dataset that consisted of 65 subjects who underwent polysomnography. An overall classification of 97 % was achieved for discrimination of the aforementioned signals, demonstrating the potential of the presented method.

Polysomnographic Characteristics of Sleep in Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Research on sleep after stroke has focused mainly on sleep disordered breathing. However, the extend to which sleep physiology is altered in stroke survivors, how these alterations compare to healthy volunteers, and how sleep changes might affect recovery as well as physical and mental health has yet to be fully researched. Motivated by the view that a deeper understanding of sleep in stroke is needed to account for its role in health and well-being as well as its relevance for recovery and rehabilitation, we conducted a systematic review and meta-analysis of polysomnographic studies comparing stroke to control populations.

METHOD

Medline and PsycInfo databases were searched using "stroke" and words capturing polysomnographic parameters as search terms. This yielded 1692 abstracts for screening, with 15 meeting the criteria for systematic review and 9 for meta-analysis. Prisma best practice guidelines were followed for the systematic review; the Comprehensive Meta-Analysis software was used for random effects modelling.

RESULTS

The meta-analysis revealed that patients with stroke have poorer sleep than controls. Patients had lower sleep efficiency (mean 75% vs 84%), shorter total-sleep-time (309.4 vs 340.3 min) and more wake-after-sleep-onset (97.2 vs 53.8 min). Patients also spend more time in stage 1 (13% vs 10%) and less time in stage 2 sleep (36% vs 45%) and slow-wave-sleep (10% vs 12%). No group differences were identified for REM sleep. The systematic review revealed a strong bias towards studies in the early recovery phase of stroke, with no study reporting specifically on patients in the chronic state. Moreover, participants in the control groups included community samples as well as other patients groups.

CONCLUSIONS

These results indicate poorer sleep in patients with stroke than controls. While strongly suggestive in nature, the evidence base is limited and methodologically diverse, and hands a clear mandate for further research. A particular need regards polysomnographic studies in chronic community-dwelling patients compared to age-matched individuals.