Effects of obstructive sleep apnea on cognitive function: a comparison between younger and older OSAS patients

Excessive daytime sleepiness in young and middle-aged Chinese adults with obstructive sleep apnea: implications for cognitive dysfunction

OBJECTIVE

The objective of this study was to investigate the effects of excessive daytime sleepiness (EDS) on cognitive function among Chinese young and middle-aged Chinese patients with obstructive sleep apnea (OSA).

METHODS

Chinese adults struggling from moderate to severe OSA with apnea-hypopnea index (AHI) ≥ 15 events per hour and adults with primary snoring and mild OSA (AHI < 15 events per hour) were included in the study. The Epworth Sleepiness Scale measured hypersomnia, and cognitive function was assessed using the Mini-mental State Examination (MMSE) and Montreal Cognitive Assessment (MOCA).

RESULTS

In comparison to the primary snoring and mild OSA group (n=635), the moderate to severe OSA group (n=1423) tended to be older men with higher scores on the Epworth Sleepiness Scale (ESS), as well as higher levels of oxygen desaturation (ODI) and a higher body mass index (BMI). Patients with moderate to severe OSA had fewer years of education, lower minimum arterial oxygen saturation (min-SaO2), and more severe sleep disturbances, such as decreased slow wave sleep (SWS) and rapid eye movement (REM) and increased non-REM stages (N1 and N2). Comorbid conditions such as hypertension and diabetes mellitus were more common in these patients (P < 0.01 and P < 0.05, accordingly). Only the delayed recall scores were statistically lower in the moderate to severe OSA group than the primary snoring and mild OSA group (P < 0.05). The main factor associated with delayed recall was the ESS score rather than age or years of education among moderate-severe OSA patients ≤ 40 years of age (P < 0.05). After controlling for potential confounding factors such as age, gender, BMI, education, hypertension, diabetes, sleep stages (SWS and REM), minimum arterial oxygen saturation (min-SaO2), oxygen ODI, and AHI, there was a negative correlation between the Epworth Sleepiness Scale (ESS) score and the delayed recall scores.

CONCLUSION

Patients with moderate to severe OSA had cognitive dysfunction, particularly impairment of delayed recall. Excessive daytime sleepiness (EDS) was significantly associated with cognitive dysfunction in young and middle-aged patients with OSA.

Lower urinary tract symptoms in young-middle aged males with a diagnosis of obstructive sleep apnea syndrome

BACKGROUND

The aim of the current study is to measure the prevalence and the potential role of International Prostate Symptom Score (IPSS) score as a predictor of obstructive sleep apnea syndrome (OSAS) in male experienced lower urinary tract symptoms (LUTS).

METHODS

A cross-sectional web-based Italian survey was administered via Google Forms between July 17 and October 31, 2022. The urinary functioning was measured through the IPSS questionnaire. Specifically, we considered symptoms occurring more than "about half the time" (score ≥ 3) as bothering symptoms. Multivariable logistic regression models (LRMs) adjusting for age, body mass index (BMI), International Index of Erectile Function-5, IPSS, and hypertension were fitted to predict OSAS in the cohort of men responding to the survey and experiencing LUTS.

RESULTS

Overall, 58 (24.4%) patients had a confirmed diagnosis of OSAS. The overall median IPSS was 5 (inter quartile range [IQR]: 3-8), respectively. According to IPSS items, 24 (10%), 44 (18.4%), 12 (5%), 12 (5%), 12 (5%), 11 (4.6%), 63 (26.4%) patients exhibit incomplete bladder emptying, urinary frequency, intermittency, urgency, weak stream, straining, nocturia with a score ≥ 3, respectively. After multivariable LRMs predicting the developing OSAS, age (odds ratio [OR]: 1.09, p < 0.001), BMI (OR:1.12, p < 0.001) and IPSS total score (OR:1.08, p = 0.02) were independent predicting factors.

CONCLUSION

This analysis revealed that the IPSS total score, age, and BMI are independent predictors of OSAS in males. In this context, the use of IPSS in daily practice could be helpful in assessing the LUTS presence and in supporting physicians to identify a hidden sleep apnea condition.

Obstructive Sleep Apnea Among Patients with Mild Cognitive Impairment

Background

Obstructive sleep apnea (OSA) is associated with cognitive disorders, but little is known about prevalence of co-occurring OSA and mild cognitive impairment (MCI) as well as about co-occurring OSA and Alzheimer's disease (AD). Pathophysiological models integrating OSA, cognitive deficits and neurodegeneration remain speculative. Findings in this area could contribute to the knowledge about pathophysiological processes in cognitive disorders and neurodegenerative processes, be helpful for the diagnosis of cognitive disorders and provide approaches for the treatment of cognitive disorders.

Objective

Examining the prevalence of OSA and patterns of cognitive deficits as well as AD biomarker profiles associated with OSA in a cohort of 104 MCI patients.

Methods

Assessments used include: respiratory polygraphy, The Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Battery (CERAD NB), Tau, phosphoTau181, amyloid-β-1-42/1-40, 18F-fluorodeoxyglucose positron emission tomography (F18-FDG-PET).

Results

Prevalence of OSA of any severity: 58,7% (Apnea Hypopnea Index (AHI)≥5/h), OSA in a moderate-to-severe extent (AHI≥15/h): 25%. Only 13.1% of MCI patients with OSA reported daytime sleepiness. MCI-OSA patients showed no specific neuropsychological pattern. Presence of OSA was not associated with specific AD biomarker profiles in the whole study group besides a positive association between AD positivity in an AD biomarker sub cohort.

Conclusions

OSA is highly prevalent in patients with MCI. It might often remain undiagnosed as only a small number of MCI-OSA patients report daytime sleepiness. OSA could contribute to MCI symptoms and even to AD pathology. Further research is needed to validate these findings and to investigate possible pathophysiological relationships between OSA and MCI as well as between OSA and AD.

Summary of drug therapy to treat cognitive impairment-induced obstructive sleep apnea

Obstructive sleep apnea (OSA) is a severe sleep disorder associated with intermittent hypoxia and sleep fragmentation. Cognitive impairment is a signifi- cant and common OSA complication often described in such patients. The most commonly utilized methods in clinical OSA treatment are oral appliances and continuous positive airway pressure (CPAP). However, the current therapeutic methods for improving cognitive function could not achieve the expected efficacy in same patients. Therefore, further understanding the molecular mechanism behind cognitive dysfunction in OSA disease will provide new treatment methods and targets. This review briefly summarized the clinical manifestations of cognitive impairment in OSA disease. Moreover, the pathophysiological molecular mechanism of OSA was outlined. Our study concluded that both SF and IH could induce cognitive impairment by multiple signaling pathways, such as oxidative stress activation, inflammation, and apoptosis. However, there is a lack of effective drug therapy for cognitive impairment in OSA. Finally, the therapeutic potential of some novel compounds and herbal medicine was evaluated on attenuating cognitive impairment based on certain preclinical studies.

Cognitive Functions, Depressive and Anxiety Symptoms After One Year of CPAP Treatment in Obstructive Sleep Apnea

Objective

The study worked with depressive symptoms, anxiety score and cognitive functions in obstructive sleep apnea (OSA) patients treated with CPAP.

Methods

Eighty-one subjects with OSA and without psychiatric comorbidity were treated with CPAP for one year and completed the following scales and cognitive tests: Trail Making Test, Verbal Fluency Test, d2 Test, Beck Depression Inventory-II and Beck Anxiety Inventory. MINI ruled out psychiatric disorder. At the two months check-up, subjects were re-evaluated for depressive and anxiety symptoms, and after one year of CPAP treatment, subjects repeated cognitive tests and scales. Data about therapy adherence and effectiveness were obtained from the patient's CPAP machines.

Results

The study was completed by 59 CPAP adherent patients and eight non-adherent patients. CPAP therapy effectiveness was verified in all patients by decreasing the apnea-hypopnoea index below 5 and/or 10% of baseline values. The adherent patients significantly improved depressive and anxiety symptoms. There was also an improvement in overall performance in the attention test; however, performance in many individual items did not change. The adherent patients also improved verbal fluency and in the Part B of the Trail making test. The non-adherent group significantly increased the number of mistakes made in the d2 test; other results were non-significant.

Conclusion

According to our results, OSA patients' mood, anxiety and certain cognitive domains improved during the one-year therapy with CPAP.

Trial Registration Number

NCT03866161.

Neurocognitive evaluation of children with down syndrome and obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) treatment has been shown to improve cardiac behavioral and cognitive functions in typically developing children. Early OSAS diagnosis in children with Down syndrome (DS) would be important to prevent its complications, especially cognitive ones, but remains overlooked. The main objective of our study was to assess the cognitive function of children with DS, with and without OSAS. The second objective was to determine the impact of the therapeutic intervention on the cognitive function of children with OSAS. This study included 41 children with DS who underwent polysomnography for OSAS diagnosis and a cognitive evaluation. They were aged between 3.4 and 17.3 years and 24 (59%) were boys. Their median OAHI was 2.6 (0-31)/h of sleep, 30 (73%) were diagnosed with OSAS (15 had mild OSAS, and 15 had moderate/severe OSAS). Some scores of the Raven's colored progressive matrices were negatively correlated with the respiratory arousal index, OAHI tended to be positively correlated with Reiss behavioral problems. 24 (59%) patients received a treatment. Even if we were unable to demonstrate this formally due that only 16 children (39%) accepted a follow-up visit, some displayed improvement in their neuropsychological scores, especially those with moderate/severe OSAS after treatment. Children with DS have low intellectual abilities and more risk of developing OSAS compared to the general population, which may lead to further neurocognitive impairment. Early screening and management are important in this population to prevent any further neurocognitive delay in their development.

The Association Between Cognition of Obstructive Sleep Apnea Patients and Urinary AD7c-NTP Level: Investigation and Application

Background: Obstructive sleep apnea (OSA) is a multi-component disorder, which has many comorbidities, including cognitive impairment. Although its potential risk factors were unknown, they could affect the patient’s quality of life and long-term prognosis. Objective: The purpose of this study was to investigate the application of urinary Alzheimer’s disease-associated neurofilament protein (AD7c-NTP) levels in the assessment of cognitive impairment in OSA patients, and to analyze the predictive value of potential high-risk factors on cognitive impairment in OSA patients. Methods: 138 young and middle-aged adults were recruited and underwent overnight polysomnographic recording, Montreal Cognitive Assessment (MoCA), and urinary AD7c-NTP test. AD7c-NTP and other factors were further applied as biomarkers to develop a cognition risk prediction model. Results: Compared with the control, OSA patients showed significantly lower MoCA scores and higher urinary AD7c-NTP concentrations, while the severe OSA group appeared more significant. The urinary AD7c-NTP level of the OSA cognitive impairment group was higher than that of the non-cognitive impairment group. The results of regression analysis showed that urinary AD7c-NTP level was an independent predictor of cognitive impairment in OSA patients. Based on urinary AD7c-NTP levels and other selected factors, a multimodal prediction model for assessing the risk of cognitive impairment in OSA patients was initially established. Conclusion: The increased urinary AD7c-NTP level could be used as a relevant peripheral biomarker of cognitive impairment in OSA patients. A model using urinary AD7c-NTP combined with other factors was developed and could accurately assess the cognition risk of OSA patients.

Gender-specific association between obstructive sleep apnea and cognitive impairment among adults

OBJECTIVES

This study aims to explore the gender-specific association between obstructive sleep apnea (OSA) and cognitive impairment.

METHODS

Participants from UK biobank who have completed at least one of the five baseline cognitive tests (visuospatial memory, prospective memory, fluid intelligence, short numeric memory and reaction time) were included, which were initially divided into two groups based on gender and were further categorized into three subgroups: (1) OSA, (2) self-reported snoring but without OSA, and (3) healthy controls (without OSA or snoring). Multivariable regression analysis was performed to examine the associations among snoring, OSA and performance of each of the five cognitive domains.

RESULTS

A total of 267,889 participants (47% male, mean age: 57 years old) were included in our study. In the multivariable regression analysis, female participants in the OSA group had a higher risk of having poor prospective memory (OR: 1.24, 95% CI: 1.02～1.50, p = 0.03). Meanwhile, among female participants, OSA were inversely associated with the performances of fluid intelligence (β: 0.29, 95% CI: 0.46～-0.13, p &lt; 0.001) and short-numeric memory (β: 0.14, 95% CI: 0.35～0.08, p = 0.02). Besides, age-related subgroup analyses showed that these associations were largely reserved in younger (＜65 years old) female participants rather than older (≥65 years old) female participants. In contrast, among male participants, no significant association was observed between OSA and impairment of the five cognitive domains.

CONCLUSIONS

OSA was significantly associated with cognitive impairment at certain dimensions in female participants rather than in male participants, indicating that more special attention and timely interventions should be given to younger female OSA patients to prevent further cognitive impairment.

Sleep and Cognition: A Narrative Review Focused on Older Adults

Little is known regarding sleep's association with the traditional developmental course of late-life cognitive functioning. As the number of older adults increases worldwide, an enhanced understanding of age-related changes in sleep and cognition is necessary to slow decline and promote optimal aging. This review synthesizes the extant literature on sleep and cognitive function in healthy older adults, older adults with insomnia, and older adults with sleep apnea, incorporating information on the potential promising effects of treating poor sleep on cognitive outcomes in older adults. Unifying theories of the sleep-cognition association, possible mechanisms of action, and important unanswered questions are identified.

Abdominal Obesity: An Independent Influencing Factor of Visuospatial and Executive/Language Ability and the Serum Levels of Aβ40/Aβ42/Tau Protein

Background

Although obesity affects human health and cognitive function, the influence of abdominal obesity on cognitive function is still unclear.

Methods

The MoCA scale was used to evaluate the overall cognitive function and the function of each subitem of 196 subjects, as well as the SDMT and TMT-A scales for evaluating the attention and information processing speed. In addition, radioimmunoassay was used to detect the serum levels of Aβ40, Aβ42, and tau protein in 45 subjects. Subjects were divided into abdominal and nonabdominal obesity groups. Before and after correcting confounding factors, the differences in cognitive scale evaluation indexes and three protein levels between the two groups were compared. We also explore further the correlation between various cognitive abilities and the waist circumference/levels of the three proteins. Linear regression was used to identify the independent influencing factors of various cognitive functions and three protein levels.

Results

After correcting for multiple factors, we observed the lower scores of visuospatial function, execution, and language in the MoCA scale, as well as higher levels of Aβ40 and tau protein in the abdominal obesity group, supported by the results of correlation analysis. Abdominal obesity was identified as an independent negative influencing factor of MoCA visual space, executive power, and language scores and an independent positive influencing factor of Aβ40, Aβ42, and tau protein levels.

Conclusion

Abdominal obesity may play a negative role in visuospatial, executive ability, and language function and a positive role in the Aβ40, Aβ42, and tau protein serum levels.

Chronic Intermittent Hypoxia-Induced Aberrant Neural Activities in the Hippocampus of Male Rats Revealed by Long-Term in vivo Recording

Chronic intermittent hypoxia (CIH) occurs in obstructive sleep apnea (OSA), a common sleep-disordered breathing associated with malfunctions in multiple organs including the brain. How OSA-associated CIH impacts on brain activities and functions leading to neurocognitive impairment is virtually unknown. Here, by means of in vivo electrophysiological recordings via chronically implanted multi-electrode arrays in male rat model of OSA, we found that both putative pyramidal neurons and putative interneurons in the hippocampal CA1 subfield were hyper-excitable during the first week of CIH treatment and followed by progressive suppression of neural firing in the longer term. Partial recovery of the neuronal activities was found after normoxia treatment but only in putative pyramidal neurons. These findings correlated well to abnormalities in dendritic spine morphogenesis of these neurons. The results reveal that hippocampal neurons respond to CIH in a complex biphasic and bidirectional manner eventually leading to suppression of firing activities. Importantly, these changes are attributed to a larger extent to impaired functions of putative interneurons than putative pyramidal neurons. Our findings therefore revealed functional and structural damages in central neurons in OSA subjects.

Objective Measures of Cognitive Performance in Sleep Disorder Research

Neurocognitive tests offer objective and reliable assessment of patients' status and progress. However, there is no consensus on how to use neurocognitive assessment in sleep disorder research. An effective use of neurocognitive assessment must be based on standardized practices and have a firm theoretic basis. The aim of this review is to offer an overview of how different tests have been used in the field, mapping each test onto a corresponding cognitive domain and propose how to move forward with a suggested cognitive battery of tests covering all major cognitive domains.

Sleep apnoea in the elderly: a great challenge for the future

Due in part to overall improvements in health, the population of elderly individuals is increasing rapidly. Similarly, obstructive sleep apnoea (OSA) is both gaining increased recognition and also increasing due to the worldwide obesity epidemic. The overlap of OSA and aging is large, but there is strong plausibility for causation in both directions: OSA is associated with pathological processes that may accelerate aging and aging related processes; aging may cause physical and neurological changes that predispose to obstructive (and central) apnoea. In addition, the common symptoms (e.g. excessive daytime somnolence, defects in memory and cognition), possible physiological consequences of OSA (e.g. accelerated cardiovascular and cerebrovascular atherosclerosis), and changes in metabolic and inflammatory markers overlap with the symptoms and associated conditions seen in aging. There is also the possibility of synergy in the effects of these symptoms and conditions on quality of life, as well as a need to separate treatable consequences of OSA from age-related complaints. Taken together, the above make it essential to review the interaction of OSA and aging, both proven and suspected. The present review examines some aspects of what is known and points to the need for further investigation of the relationships, given the large number of potentially affected subjects.

The impact of aging on driving performance in patients with untreated obstructive sleep apnea

OBJECTIVE

To determine the influence of age on sleepiness-related driving performance in individuals with obstructive sleep apnea (OSA).

DESIGN

Extended wakefulness protocol comparing simulated driving performance in younger and older individuals with OSA.

PARTICIPANTS

Fifty-two individuals with OSA (15 female) were median split into younger (≤55 years, n = 26) and older (>55 years, n = 26) groups.

MEASUREMENTS

Participants underwent polysomnography to derive sleep parameters and confirm OSA diagnosis. One-to-2 weeks following polysomnography, participants completed a 60-minute driving simulation 4 hours prior to their habitual bedtime. Participants remained awake to 3 hours post habitual bedtime before repeating the task.

RESULTS

Median age was 44.5 years (25th, 75th centiles = 37.0, 48.0) for the younger group and 64.5 years (60.0, 70.0) for the older group. When comparing the performance change between baseline and extended wakefulness, the younger patients had greater deterioration on all driving simulator parameters (crashes, standard deviation of lateral position, speed deviation and braking reaction time, all p < .05), compared to the older group. Linear regression found a 10-year age increase was associated with an a ∼30%-41% reduction in crash occurrence when accounting for covariates (p = .023). Age also predicted standard deviation of lateral position deviation, but not when sleep efficiency and self-reported sleepiness were included as covariates.

CONCLUSION

Older participants with OSA were less vulnerable than younger participants to sleepiness-related driving simulator impairment when assessed at night-time following extended wakefulness. Future work should assess naturalistic on-road driving to determine if this extends to a variety of challenging driving scenarios.

Expression of sirtuin type 3 in locus ceruleus is associated with long-term intermittent hypoxia-induced neurocognitive impairment in mice

Recent studies revealed that increased oxidative stress is one of the major mechanisms underlying the cognitive dysfunction induced by long-term intermittent hypoxia (LTIH). Locus ceruleus (LC) neurons, which fire at high rate across wakefulness, are essential for optimal cognitive function. The aim of this study was to investigate whether sirtuin type 3 (SirT3), a redox responses coordinator, plays a role in LTIH-induced neurocognitive impairment. Mice were subjected to LTIH or room air [normal control (NC)] for 10 weeks (10 h/day). Morris water maze test was used to detect spatial learning and memory ability. The oxidative stress was evaluated through the level of superoxide dismutase 2 (SOD2) and dihydroethidium and ethidium (DHE). Then the correlation between the number of platform crossing and SirT3 content measured by western blot was analyzed. Results showed that performance on the Morris water maze test was significantly worse for LTIH mice than for NC mice. LTIH exposure downregulated SirT3 and SOD2 in LC neurons, increasing DHE immunodensity. In addition, the SirT3 protein levels in LC neurons were positively related to the number of platform crossing. These observations suggest that SirT3-SOD2-intracellular superoxide is a key component associated with the cognitive dysfunction induced by LTIH. Moreover, they lend support to a rational basis for targeting upregulation of SirT3 in LC as a disease modifying strategy.Video abstract: http://links.lww.com/WNR/A577.

Comparison of clinical and polysomnographic characteristics in young and old patients with obstructive sleep apnea syndrome

AIM

This study aimed to determine the differences in the clinical, demographic and polysomnographic characteristics of OSAS between patients older than and younger than 65 years of age.

METHODS

Two groups of OSAS patients under 65 years of age and older who underwent PAP treatment in our sleep center were included in the study. Demographic, clinical, and polysomnographic variables of patients were compared as well as the PAP device usage compliance.

RESULTS

The study was conducted with 183 patients (81 females and 102 males) having the diagnosis of OSAS. The ages of the patients ranged from 37 to 85 years (mean: 58.77 ± 12.59). The incidence of apnea, chest pain, arrhythmia, headache, non-concentration, forgetfulness, psychiatric disorders, motor activity, enuresis, libido and impotence complaints as well as the sedative usage rates and incidence of additional diseases were higher in elderly patients. Apnea hypopnea index, inspiratory positive airway pressure, and expiratory positive airway pressure measurements were significantly higher in the elderly group. The rates of NREM2 (%) and NREM3 (%) were lower in elderly patients.

CONCLUSION

Many comorbid medical conditions, concomitant drug use, and age-related physiological changes in sleep architecture and circadian rhythm and their effects on sleep should be considered in the elderly sleep.

Obstructive Sleep Apnea and Its Treatment in Aging: Effects on Alzheimer's disease Biomarkers, Cognition, Brain Structure and Neurophysiology

Here we review the impact of obstructive sleep apnea (OSA) on biomarkers of Alzheimer's disease (AD) pathogenesis, neuroanatomy, cognition and neurophysiology, and present the research investigating the effects of continuous positive airway pressure (CPAP) therapy. OSA is associated with an increase in AD markers amyloid-β and tau measured in cerebrospinal fluid (CSF), by Positron Emission Tomography (PET) and in blood serum. There is some evidence suggesting CPAP therapy normalizes AD biomarkers in CSF but since mechanisms for amyloid-β and tau production/clearance in humans are not completely understood, these findings remain preliminary. Deficits in the cognitive domains of attention, vigilance, memory and executive functioning are observed in OSA patients with the magnitude of impairment appearing stronger in younger people from clinical settings than in older community samples. Cognition improves with varying degrees after CPAP use, with the greatest effect seen for attention in middle age adults with more severe OSA and sleepiness. Paradigms in which encoding and retrieval of information are separated by periods of sleep with or without OSA have been done only rarely, but perhaps offer a better chance to understand cognitive effects of OSA than isolated daytime testing. In cognitively normal individuals, changes in EEG microstructure during sleep, particularly slow oscillations and spindles, are associated with biomarkers of AD, and measures of cognition and memory. Similar changes in EEG activity are reported in AD and OSA, such as "EEG slowing" during wake and REM sleep, and a degradation of NREM EEG microstructure. There is evidence that CPAP therapy partially reverses these changes but large longitudinal studies demonstrating this are lacking. A diagnostic definition of OSA relying solely on the Apnea Hypopnea Index (AHI) does not assist in understanding the high degree of inter-individual variation in daytime impairments related to OSA or response to CPAP therapy. We conclude by discussing conceptual challenges to a clinical trial of OSA treatment for AD prevention, including inclusion criteria for age, OSA severity, and associated symptoms, the need for a potentially long trial, defining relevant primary outcomes, and which treatments to target to optimize treatment adherence.

Associations between hypoxia parameters in obstructive sleep apnea and cognition, cortical thickness, and white matter integrity in middle-aged and older adults

OBJECTIVE

This study aimed to investigate the association between each parameter of intermittent hypoxia in obstructive sleep apnea (OSA) and the cognitive profile, cortical thickness, and white matter integrity in middle-aged and older adults.

METHODOLOGY

Participants were newly diagnosed with moderate or severe OSA from the King Chulalongkorn Memorial Hospital, Bangkok, Thailand. Respiratory parameters from polysomnography were extracted. Each participant was tested on a battery of neuropsychological tests and underwent an MRI scan of the brain. Cortical thickness analysis and diffusion tensor imaging analysis were performed. Participants were classified as having either severe or mild hypoxia based on parameters of hypoxia, i.e., oxygen desaturation index, lowest oxygen saturation, and the percentage of total sleep time spent below 90% oxygen saturation.

RESULTS

Of 17 patients with OSA, there were 8 men (47%). Median age was 57 years and median AHI was 60.6. Comparison of cortical thickness between the severe and the mild group of each hypoxic parameter revealed two clusters of cortical thinning at the right inferior frontal gyrus (p-value = 0.008) and right inferior parietal gyrus (p-value = 0.006) in the severe desaturation group and a cluster of cortical thinning at the superior parietal gyrus (p-value = 0.008) in the high oxygen desaturation index group. There was no difference in cognitive function or white matter integrity between groups.

CONCLUSIONS

The magnitude of the degree and frequency of desaturations in OSA are associated with a decrease in cortical thickness at the frontal and parietal regions.

Correlates of Endothelial Function in Older Adults With Untreated Obstructive Sleep Apnea and Cardiovascular Disease

BACKGROUND

Obstructive sleep apnea (OSA) is a highly prevalent and consequential sleep disorder in older adults. Untreated moderate to severe OSA substantially increases the risk for hypertension and cardiovascular disease (CVD), which can be attributed to the accelerated progression of atherosclerosis and endothelial dysfunction.

OBJECTIVE

The aim of this study was to identify factors that can function as correlates of endothelial function in older adults with untreated, moderate to severe OSA and CVD or CVD risk factors.

METHODS

A subsample (N = 126) of adults aged 65 years and older from the HeartBEAT study were included in the analyses. Univariate analyses and multiple linear regression models were conducted to establish which demographic and CVD risk factors were the best correlates of endothelial function.

RESULTS

In the univariate analyses, sex, employment status, body mass index, waist circumference, hip-to-waist ratio, neck circumference, diastolic blood pressure, total cholesterol, high-density lipoprotein cholesterol, total cholesterol to high-density lipoprotein cholesterol ratio, plasminogen activator inhibitor-1, calcium channel blocker use, and β-blocker use were associated with endothelial function at a level of P < .10. In the most parsimonious model, male sex (b = -0.305, P < .001), calcium channel blocker use (b = -0.148, P < .019), and body mass index (b = -.014, P < .037) were negatively associated with endothelial function after adjusting for the other covariates.

CONCLUSIONS

The authors identified correlates of endothelial function in older adults with untreated OSA and CVD or CVD risk factors, which are different than the correlates in middle-aged adults with the same conditions.

Obstructive sleep apnea, cognition and Alzheimer's disease: A systematic review integrating three decades of multidisciplinary research

Increasing evidence links cognitive-decline and Alzheimer's disease (AD) to various sleep disorders, including obstructive sleep apnea (OSA). With increasing age, there are substantial differences in OSA's prevalence, associated comorbidities and phenotypic presentation. An important question for sleep and AD researchers is whether OSA's heterogeneity results in varying cognitive-outcomes in older-adults compared to middle-aged adults. In this review, we systematically integrated research examining OSA and cognition, mild cognitive-impairment (MCI) and AD/AD biomarkers; including the effects of continuous positive airway pressure (CPAP) treatment, particularly focusing on characterizing the heterogeneity of OSA and its cognitive-outcomes. Broadly, in middle-aged adults, OSA is often associated with mild impairment in attention, memory and executive function. In older-adults, OSA is not associated with any particular pattern of cognitive-impairment at cross-section; however, OSA is associated with the development of MCI or AD with symptomatic patients who have a higher likelihood of associated disturbed sleep/cognitive-impairment driving these findings. CPAP treatment may be effective in improving cognition in OSA patients with AD. Recent trends demonstrate links between OSA and AD-biomarkers of neurodegeneration across all age-groups. These distinct patterns provide the foundation for envisioning better characterization of OSA and the need for more sensitive/novel sleep-dependent cognitive assessments to assess OSA-related cognitive-impairment.

Lifestyle Choices and Brain Health

This article is largely based on the recommendations of the AARP's Global Council on Brain Health (GCBH) and aims to provide an overview of evidence from current literature and expert opinion on key elements known to be relevant in preserving brain health as people age. Although we realize that there may be other lifestyle choices of importance to brain health, the GCBH has decided to initially focus on the issues below based on the preferences and concerns of its members. The areas to be discussed are: mental well-being, exercise, cognitively stimulating activities, sleep, nutrition, and social connectedness. Our review concluded that each of these areas offer opportunities for aging individuals to make lifestyle adjustments to positively impact brain health.

Electrophysiological assessment of the concentration and attention in patient with nasal polyposis

Background

Nasal polyposis is a chronic disease presenting with nasal obstruction as the most frequent complaint. It has been documented that nasal polyposis results in deterioration of quality of life and disturbances of sleep. However, remarkable consequences of nasal polyposis such as psychological and cognitive outcomes are relatively poorly studied.

Objective

The aim of the present study was to evaluate whether there is an impairment of concentration and attention in nasal polyposis patients due to hypoxia caused by nasal obstruction.

Methods

This cross-sectional, case-control study was carried out on 30 male patients with nasal polyps and 30 healthy subjects serving as controls. Participant ages were 41.6 ± 10.2 years in the nasal polyps group and 41.3 ± 6.2 in the control group. All participants underwent systemic, neurological, and otorhinolaryngological examinations together with routine hematological and biochemical tests. Patients with nasal polyposis had bilateral complete obstruction of nasal cavity. P300 component of electroencephalography-derived event related potentials were used to monitor concentration and attention. Nasal polyposis and control groups were compared in terms of amplitude and latency of P300.

Results

There were significant differences between control and nasal polyposis groups in terms of latency of P300 (p < 0.001). Nasal polyposis patient latencies in P300 were longer than controls (345.8 ± 16.6 msec, 309.3 ± 16.6 msec, respectively). However, there were no significant differences between control and nasal polyposis groups in terms of amplitude of P300 (p > 0.05).

Conclusion

Results of the current study indicate that hypoxia due to complete nasal obstruction may result in impairment of attention and concentration in nasal polyposis patients. Assessment of patients with P300 latency subcomponent can be a useful diagnostic tool to detect cognitive and psychological consequences.

Neurobehavioral Impairment and CPAP Treatment Response in Mild-Moderate Obstructive Sleep Apneas

STUDY OBJECTIVES

The degree of neurobehavioral impairment and treatment response in mild-moderate obstructive sleep apnea (OSA) compared to that of an appropriate control group are unclear. This study compared neurobehavioral function and response to continuous positive airway pressure (CPAP) treatment in patients with mild to moderate OSA with those of a non-sleep apneic community sample of similar demography.

METHODS

One hundred ten patients with OSA and 31 asymptomatic community dwellers underwent overnight polysomnography and neurobehavioral testing. Participants with OSA (n = 88) were treated with CPAP for 3 months, and repeat evaluations were performed at the end of the treatment period.

RESULTS

Compared to the community sample, participants with OSA were significantly sleepier, had impaired mood and quality of life, and showed decrements in neuropsychological function, specifically psychomotor function, working memory and vigilance. Some neuropsychological and mood outcomes were normalized with CPAP, but significant decrements persisted in most outcomes even in those participants with adequate device usage.

CONCLUSIONS

Patients with mild to moderate OSA have significant neurobehavioral morbidity. During "gold standard" treatment, normal function was not achieved, even with adequate device usage. CPAP efficacy for improving sleepiness and neuropsychological function in this milder end of the OSA spectrum may be poor, which may affect CPAP adherence. These findings suggest that there may be neurological changes related to OSA that do not respond to CPAP treatment, the etiology of which requires further investigation.

Sleep and Cognition in Older Adults

Increased age is associated with normative declines in both sleep and cognitive functioning. Although there are some inconsistencies in the literature, negative sleep changes are associated with worse cognitive functioning. This negative relationship holds true across normal-sleeping older adults, older adults with insomnia, older adults with sleep disordered breathing, cognitively healthy older adults, and older adults with dementia. There are mixed results regarding potential benefits of sleep treatments on cognitive functions; however, this line of research deserves added attention because the potential mechanisms of action are likely distinct from other interventions to improve cognition.

Sleep disordered breathing in older adults with heart failure with preserved ejection fraction

Heart failure in older adults is frequently accompanied by sleep disordered breathing (SDB). Treatment of SDB in persons with heart failure with preserved ejection fraction (HFpEF) is unclear because most data is on heart failure with reduced ejection fraction (HFrEF). The purpose of this paper was to evaluate studies that report on the effects of positive airway pressure on patient outcomes in older adults with HFpEF and comorbid SDB. A search of the literature found six data-based studies (N = 36 to 126). Treatment with positive airway pressure reduced nighttime SDB symptoms and improved daytime functional status in persons with HFPEF and SDB (New York Heart Association Functional Class: effect sizes = -0.67 to -1.60). Limitations (i.e. only two studies were randomized controlled trials, small sample sizes, and women were under-represented) suggest that additional evidence is needed to guide treatment of SDB in older adults with HFpEF.

Is Obstructive Sleep Apnoea Related to Neuropsychological Function in Healthy Older Adults? A Systematic Review and Meta-Analysis

Previous systematic reviews and meta-analyses have identified cognitive deficits in adults with obstructive sleep apnoea (OSA). However, quantitative analysis of the association between OSA and neuropsychological performance has not been conducted specifically in older adults, for whom there is a greater risk of cognitive decline. We searched Medline, Embase and PsycINFO through August 2016 for studies describing associations between OSA and neuropsychological outcomes in people aged>50 years. Meta-analyses were performed on these studies for overall cognition and within cognitive domains. Subgroup analyses were performed taking into account risk of bias and moderating differences in study design. 13 studies met eligibility criteria for analysis. A small negative association was found between OSA and all neuropsychological outcomes combined, g=0.18(95% CI 0.04-0.32), and in memory and processing speed domains. Small case-control studies from sleep clinic populations observed the greatest associations, while larger cohort studies from community samples illustrated no association. Analysis accounting for publication bias resulted in a null overall association, g=0.02 (95%CI -0.12 to 0.16). Associations between OSA and cognition in later life are highly variable and the findings differ based on the type and setting of study. It appears some older adults may be at risk of cognitive impairments attributable to OSA; however, the risk of bias renders the evidence inconclusive. High quality research is warranted in clinically diagnosed OSA patients as well as those already experiencing neuropsychological impairment and who may be regarded at higher risk of further cognitive decline.

Memory and Executive Screening for the Detection of Cognitive Impairment in Obstructive Sleep Apnea

BACKGROUND

Obstructive sleep apnea (OSA) is commonly associated with cognitive dysfunction, which is more apparent in severe OSA and impairs quality of life. However, the clinical screening methods for these impairments in OSA are still limited. In this study, we evaluated the feasibility of using the Memory and Executive Screening (MES) for assessing cognitive performance in OSA.

MATERIALS AND METHODS

Twenty-four patients with nonsevere OSA and 36 patients with severe OSA participated in this study. All participants underwent comprehensive, laboratory-based polysomnography and completed assessments of cognitive function, which included both the MES and the Beijing version of the Montreal Cognitive Assessment (MoCA-BJ).

RESULTS

Both the total MES scores and 5 recall scores of the MES (MES-5R) were significantly lower in the severe OSA group than those in the nonsevere OSA group. The patients with severe OSA performed worse on the memory subtests of the MES-5R, especially on immediate recall. The sensitivity and specificity of the MES for identifying cognitive impairment in patients with OSA were 63.89% and 66.67%, respectively, for a cutoff value of <92 out of 100 points. An optimal cutoff between nonsevere and severe OSA was also set at 45 points (MES-5R) and at 0.94 points (MES ratio). Compared with the MES, the MoCA-BJ had similar sensitivity (61.11%) and specificity (66.67%).

CONCLUSIONS

The MES is an acceptable tool for detecting cognitive dysfunction in patients with OSA. The sensitivity and specificity of the MES were similar to those of the MoCA-BJ. The MES-5R and total MES scores can assess the presence and severity of cognitive impairment in patients with severe OSA.

Adherence to Continuous Positive Airway Pressure in Existing Users: Self-Efficacy Enhances the Association between Continuous Positive Airway Pressure and Adherence

STUDY OBJECTIVES

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common sleep disorder associated with a myriad of sequelae. OSAHS is effectively treated with continuous positive airway pressure (CPAP) therapy. However, fewer than 50% of patients are compliant with their CPAP therapy prescriptions. The current study sought to explore an integrated, biopsychological approach to CPAP adherence among experienced CPAP users.

METHODS

We performed a retrospective, cross-sectional analysis of a cohort of veterans with a diagnosis of OSAHS (n = 191) who were prescribed CPAP therapy and returned for adherence download at the Miami VA Sleep Clinic. The relationships between biomedical characteristics (e.g., CPAP pressure, self-reported sleepiness, and change in sleep efficiency) and psychological factors (e.g., self-efficacy beliefs and psychological diagnoses) and objectively measured CPAP use were examined to determine whether psychological factors moderated the relationships between biomedical characteristics and CPAP adherence.

RESULTS

Hierarchical regression analyses predicting CPAP adherence (adjusting for time since CPAP prescription, age, education, prescribed CPAP pressure, daytime sleepiness, changes in sleep efficiency with CPAP, and psychiatric conditions) revealed the following: (1) CPAP self-efficacy and CPAP pressure were positively related to adherence, and (2) CPAP self-efficacy moderates the relationship between CPAP pressure and CPAP adherence.

CONCLUSIONS

There was no relationship between CPAP pressure and adherence in individuals with low self-efficacy beliefs. However, for individuals with high self-efficacy beliefs, there was a significant positive relationship between CPAP pressure and adherence. Self-efficacy beliefs appear to be a prime target for focused interventions aimed at improving CPAP adherence among those individuals with higher pressure prescriptions.

Emerging co-morbidities of obstructive sleep apnea: cognition, kidney disease, and cancer

Obstructive sleep apnea (OSA) causes daytime fatigue and sleepiness, and has an established relationship with cardiovascular and metabolic disease. Recent years have seen the emergence of an evidence base linking OSA with an increased risk of degenerative neurological disease and associated cognitive impairment, an accelerated rate of decline in kidney function with an increased risk of clinically significant chronic kidney disease (CKD), and with a significantly higher rate of cancer incidence and death. This review evaluates the evidence base linking OSA with these seemingly unrelated co-morbidities, and explores potential mechanistic links underpinning their development in patients with OSA, including intermittent hypoxia (IH), sleep fragmentation, sympathetic excitation, and immune dysregulation.

A multicentre randomised controlled trial and economic evaluation of continuous positive airway pressure for the treatment of obstructive sleep apnoea syndrome in older people: PREDICT

BACKGROUND

The therapeutic and economic benefits of continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnoea syndrome (OSAS) have been established in middle-aged people. In older people there is a lack of evidence.

OBJECTIVE

To determine the clinical efficacy of CPAP in older people with OSAS and to establish its cost-effectiveness.

DESIGN

A randomised, parallel, investigator-blinded multicentre trial with within-trial and model-based cost-effectiveness analysis.

METHODS

Two hundred and seventy-eight patients, aged ≥ 65 years with newly diagnosed OSAS [defined as oxygen desaturation index at ≥ 4% desaturation threshold level for > 7.5 events/hour and Epworth Sleepiness Scale (ESS) score of ≥ 9] recruited from 14 hospital-based sleep services across the UK.

INTERVENTIONS

CPAP with best supportive care (BSC) or BSC alone. Autotitrating CPAP was initiated using standard clinical practice. BSC was structured advice on minimising sleepiness.

COPRIMARY OUTCOMES

Subjective sleepiness at 3 months, as measured by the ESS (ESS mean score: months 3 and 4) and cost-effectiveness over 12 months, as measured in quality-adjusted life-years (QALYs) calculated using the European Quality of Life-5 Dimensions (EQ-5D) and health-care resource use, information on which was collected monthly from patient diaries.

SECONDARY OUTCOMES

Subjective sleepiness at 12 months (ESS mean score: months 10, 11 and 12) and objective sleepiness, disease-specific and generic quality of life, mood, functionality, nocturia, mobility, accidents, cognitive function, cardiovascular risk factors and events at 3 and 12 months.

RESULTS

Two hundred and seventy-eight patients were randomised to CPAP (n = 140) or BSC (n = 138) over 27 months and 231 (83%) patients completed the trial. Baseline ESS score was similar in both groups [mean (standard deviation; SD) CPAP 11.5 (3.3), BSC 11.4 (4.2)]; groups were well balanced for other characteristics. The mean (SD) in ESS score at 3 months was -3.8 (0.4) in the CPAP group and -1.6 (0.3) in the BSC group. The adjusted treatment effect of CPAP compared with BSC was -2.1 points [95% confidence interval (CI) -3.0 to -1.3 points; p < 0.001]. At 12 months the effect was -2.0 points (95% CI -2.8 to -1.2 points; p < 0.001). The effect was greater in patients with increased CPAP use or higher baseline ESS score. The number of QALYs calculated using the EQ-5D was marginally (0.005) higher with CPAP than with BSC (95% CI -0.034 to 0.044). The average cost per patient was £1363 (95% CI £1121 to £1606) for those allocated to CPAP and £1389 (95% CI £1116 to £1662) for those allocated to BSC. On average, costs were lower in the CPAP group (mean -£35; 95% CI -£390 to £321). The probability that CPAP was cost-effective at thresholds conventionally used by the NHS (£20,000 per QALY gained) was 0.61. QALYs calculated using the Short Form questionnaire-6 Dimensions were 0.018 higher in the CPAP group (95% CI 0.003 to 0.034 QALYs) and the probability that CPAP was cost-effective was 0.96. CPAP decreased objective sleepiness (p = 0.02), increased mobility (p = 0.03) and reduced total and low-density lipoprotein cholesterol (p = 0.05, p = 0.04, respectively) at 3 months but not at 12 months. In the BSC group, there was a fall in systolic blood pressure of 3.7 mmHg at 12 months, which was not seen in the CPAP group (p = 0.04). Mood, functionality, nocturia, accidents, cognitive function and cardiovascular events were unchanged. There were no medically significant harms attributable to CPAP.

CONCLUSION

In older people with OSAS, CPAP reduces sleepiness and is marginally more cost-effective than BSC over 12 months. Further work is required in the identification of potential biomarkers of sleepiness and those patients at increased risk of cognitive impairment. Early detection of which could be used to inform the clinician when in the disease cycle treatment is needed to avert central nervous system sequelae and to assist patients decision-making regarding treatment and compliance. Treatment adherence is also a challenge in clinical trials generally, and adherence to CPAP therapy in particular is a recognised concern in both research studies and clinical practice. Suggested research priorities would include a focus on optimisation of CPAP delivery or support and embracing the technological advances currently available. Finally, the improvements in quality of life in trials do not appear to reflect the dramatic changes noted in clinical practice. There should be a greater focus on patient centred outcomes which would better capture the symptomatic improvement with CPAP treatment and translate these improvements into outcomes which could be used in health economic analysis.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN90464927.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 40. See the NIHR Journals Library website for further project information.

A review of neurocognitive function and obstructive sleep apnea with or without daytime sleepiness

Excessive daytime sleepiness (EDS) and neurocognitive dysfunction are commonly observed in patients with obstructive sleep apnea (OSA), and these daytime functional deficits can be reversed partly or completely with treatment such as continuous positive airway pressure (CPAP). Although daytime sleepiness is a possible etiology for neurocognitive dysfunction in OSA patients, EDS is not universally present in all patients with OSA. The objective of this review is to summarize the relationship between neurocognitive function and EDS in OSA, as well as the difference in cognitive domains, improvement, and application of CPAP therapy between patients with and without EDS. Two authors independently searched PubMED/Medline, The Cochrane Library and Scopus through May 27, 2015. Sixty-five articles were included in this review. The literature demonstrated a wide range of neurocognitive deficits in OSA patients with EDS, but no more extensive and complex cognitive domains (eg, executive function) in patients without EDS. However, the current literature had very few studies with large sample sizes and extended follow-up that evaluated the effect of CPAP for OSA in patients with and without sleepiness. CPAP failed to improve cognitive dysfunction in OSA patients without EDS after short-term therapy. The evidence suggests that daytime sleepiness possibly relates to the domain and extent of cognitive impairments in OSA, and CPAP therapy has little effect on the improvement of cognitive deficits in OSA patients without EDS. We recommend that additional prospective studies be performed to further quantify the relationship between neurocognitive function in OSA patients with and without EDS.

Sleep disordered breathing at the extremes of age: the elderly

KEY POINTS

Sleep disordered breathing (SDB) is common and its prevalence increases with age. Despite this high prevalence, SDB is frequently unrecognised and undiagnosed in older people.There is accumulating evidence that SDB in older people is associated with worsening cardio- cerebrovascular, cognitive and functional outcomes.There is now good evidence to support the use of continuous positive airway pressure therapy in older patients with symptomatic SDB.

EDUCATIONAL AIMS

To highlight the prevalence and presentation of sleep disordered breathing (SDB) in older people.To inform readers about the risk factors for SDB in older people.To explore the impact of SDB in older people.To introduce current evidence based treatment options for SDB in older people. Sleep disordered breathing (SBD) increases in prevalence as we age, most likely due to physiological and physical changes that occur with ageing. Additionally, SDB is associated with comorbidity and its subsequent polypharmacy, which may increase with increasing age. Finally, the increased prevalence of SDB is intrinsically linked to the obesity epidemic. SDB is associated with serious outcomes in younger people and, likewise, older people. Thus, identification, diagnosis and treatment of SDB is important irrelevant of age. This article reviews the age-related changes contributing to SDB, the epidemiology and the risk factors for SDB in older people, the association of SDB with adverse outcomes, and diagnostic and treatment options for this population.

Protocatechuic acid ameliorates neurocognitive functions impairment induced by chronic intermittent hypoxia

Chronic intermittent hypoxia (CIH) is a serious consequence of obstructive sleep apnoea (OSA) and has deleterious effects on central neurons and neurocognitive functions. This study examined if protocatechuic acid (PCA) could improve learning and memory functions of rats exposed to CIH conditions and explore potential mechanisms. Neurocognitive functions were evaluated in male SD rats by step-through passive avoidance test and Morris water maze assay following exposure to CIH or room air conditions. Ultrastructure changes were investigated with transmission electron microscopy, and neuron apoptosis was confirmed by TUNEL assays. Ultrastructure changes were investigated with transmission electron microscope and neuron apoptosis was confirmed by TUNEL assays. The effects of PCA on oxidative stress, apoptosis, and brain IL-1β levels were investigated. Expression of Bcl-2, Bax, Cleaved Caspase-3, c-fos, SYN, BDNF and pro-BDNF were also studied along with JNK, P38 and ERK phosphorylation to elucidate the molecular mechanisms of PCA action. PCA was seen to enhance learning and memory ability, and alleviate oxidative stress, apoptosis and glial proliferation following CIH exposure in rats. In addition, PCA administration also decreased the level of IL-1β in brain and increased the expression of BDNF and SYN. We conclude that PCA administration will ameliorate CIH-induced cognitive dysfunctions.

Critical Role of Endoplasmic Reticulum Stress in Chronic Intermittent Hypoxia-Induced Deficits in Synaptic Plasticity and Long-Term Memory

AIMS

This study examined the role of endoplasmic reticulum (ER) stress in mediating chronic intermittent hypoxia (IH)-induced neurocognitive deficits. We designed experiments to demonstrate that ER stress is initiated in the hippocampus under chronic IH and determined its role in apoptotic cell death, impaired synaptic structure and plasticity, and memory deficits.

RESULTS

Two weeks of IH disrupted ER fine structure and upregulated ER stress markers, glucose-regulated protein 78, caspase-12, and C/EBP homologous protein, in the hippocampus, which could be suppressed by ER stress inhibitors, tauroursodeoxycholic acid (TUDCA) and 4-phenylbutyric acid. Meanwhile, ER stress induced apoptosis via decreased Bcl-2, promoted reactive oxygen species production, and increased malondialdehyde formation and protein carbonyl, as well as suppressed mitochondrial function. These effects were largely prevented by ER stress inhibitors. On the other hand, suppression of oxidative stress could reduce ER stress. In addition, the length of the synaptic active zone and number of mature spines were reduced by IH. Long-term recognition memory and spatial memory were also impaired, which was accompanied by reduced long-term potentiation in the Schaffer collateral pathway. These effects were prevented by coadministration of the TUDCA.

INNOVATION AND CONCLUSION

These results show that ER stress plays a critical role in underlying memory deficits in obstructive sleep apnea (OSA)-associated IH. Attenuators of ER stress may serve as novel adjunct therapeutic agents for ameliorating OSA-induced neurocognitive impairment.

Reliability and Validity of the Beijing Version of the Montreal Cognitive Assessment in the Evaluation of Cognitive Function of Adult Patients with OSAHS

Background

The patients with obstructive sleep apnea hypopnea syndrome (OSAHS) tend to develop cognitive deficits, which usually go unrecognized, and can affect their daily life. The Beijing version of the Montreal cognitive assessment (MoCA-BJ), a Chinese version of MoCA, has been used for the assessment of cognitive functions of OSAHS patients in clinical practice. So far, its reliability and validity have not been tested. This study examined the reliability and validity of MoCA-BJ in a cohort of adult OSAHS patients.

Methods

152 OSAHS patients, ranging from mild, moderate to severe, 49 primary snoring subjects and 40 normal controls were evaluated for cognitive functions by employing both MoCA-BJ and the Mini Mental State Examination (MMSE). Forty of them were re-tested by MoCA-BJ 14 days after the first test. Internal consistency, test-retest reliability, discriminate and concurrent validity of MoCA-BJ were analyzed.

Results

Internal consistency reliability by Cronbach’s alpha was adequate (0.73). Intra-class correlation coefficient (ICC), an measure of test-retest reliability, was 0.87 (P<0.001). The total MoCA-BJ scores were significant higher in normal controls than in OSAHS groups (p<0.05). The performances of visuospatial ability in severe OSAHS group were significantly weaker than in normal controls and primary snoring group. The performances of executive ability in severe OSAHS patients were weaker than in normal controls. An optimal cut-off between normal controls and non-normal subjects was at 26 points (total MoCA score). Moreover, cut-off between non-severe and severe OSAHS was at 2 points on visuospatial subscale. Analysis of the correlation between MoCA total scores and MMSE total scores revealed a statistically significant, though relatively weak, correlation (r=0.41, P<0.05).

Conclusion

In conclusion, our study showed that the Beijing version of the MoCA was reliable and stable. The MoCA-BJ was capable of detecting cognitive dysfunction by visuospatial and total MoCA-BJ score.

Combined effect of obstructive sleep apnea and chronic smoking on cognitive impairment

OBJECTIVES

Little is known about combined effect of obstructive sleep apnea (OSA) and chronic smoking on cognitive impairment. We aimed to determine whether smoking synergizes with OSA in deteriorating cognitive function and whether smoking cessation contributes to cognitive benefits.

METHODS

One hundred and eighteen male patients were enrolled in the study and asked to complete neurocognitive function tests including Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), clock drawing test (CDT), and verbal fluency test (VFT). Variables of those neurocognitive function tests were analyzed with two factors: OSA and smoking.

RESULTS

After adjustment of potential confounding factors, an OSA-by-smoking interaction was found in CDT-C scores and a main smoking effect were showed in MoCA scores. Smoking patients with OSA had the worst performance in the four tests compared with the other three groups (smoking patients without OSA, non-smoking patients with and without OSA). Ex-smokers with OSA tended to perform better than current smokers, but still worse than never-smokers with OSA in those tests.

CONCLUSION

The results suggested that the coexistence of OSA and chronic smoking resulted in more pronounced cognitive deficits than either factor along. Smoking cessation may benefit cognitive function to some extents in patients with OSA.

Sleep breathing disorders and cognitive function in the elderly: an 8-year follow-up study. the proof-synapse cohort

STUDY OBJECTIVES

Sleep breathing disorder (SBD) may be an important factor in age-related cognitive decline. In a cohort of healthy elderly subjects, we performed an 8-y longitudinal study to assess whether changes in cognitive function occur in untreated elderly patients with SBD and without dementia and the factors implicated in these changes.

DESIGN

A population-based longitudinal study.

SETTING

Clinical research settings.

PARTICIPANTS

A total of 559 participants of the PROOF study aged 67 y at the study entry and free from neurological disorders were examined.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Abnormal breathing events were defined by an apnea-hypopnea index (AHI) > 15. The raw cognitive data and averaged Z-scores for the attentional, executive, and memory functions were collected at the baseline and follow-up. At baseline, AHI > 15 was found in 54% of subjects with 18% having an AHI > 30. At follow-up, the presence of abnormal breathing events was associated with a slight but significant decline in the attentional domain (P = 0.01), which was more evident in the subjects with an AHI > 30 (P = 0.004). No significant changes over time were observed in the executive and memory functions. Several indices of chronic hypoxemia, defined either as a cumulative peripheral oxygen saturation (SpO2) < 90% or a minimal SpO2, accounted for portions of the variance in the decline in attention. All observed effects were small, accounting for 4-7% of variance in multivariate models.

CONCLUSION

In healthy elderly subjects, various components of sleep breathing disorder at baseline were associated with small changes in selected cognitive functions specific to the attention domain after controlling for multiple comorbidities, such as sleepiness, hypertension, diabetes, anxiety, and depression.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifiers NCT 00759304 and NCT 00766584.

Supporting a happy, healthy adolescence for young people with Down syndrome and other intellectual disabilities: recommendations for clinicians

PURPOSE OF REVIEW

To review clinical updates and current healthcare issues for adolescents with Down syndrome and intellectual disabilities, including behavioral, social, and emotional issues, health supervision recommendations, and recommendations for supporting the transition process.

RECENT FINDINGS

Several recent findings merit particular attention: low activity levels and implications for overweight and poor bone density; high prevalence of obstructive sleep apnea and its implications; prevalence of mental health and behavioral concerns; and need for appropriate transition services.

SUMMARY

In guiding adolescents with Down syndrome towards healthy productive adult lives, clinicians can make use of healthcare guidelines and should also take a broader, more interdisciplinary approach to ensure that social, educational, and vocational plans are in place to support physical and mental health and development during transition into adulthood. Many of these issues have broader applicability to any adolescent with an intellectual disability.

Cognitive impairment in obstructive sleep apnea

Obstructive sleep apnea (OSA) is characterised by repetitive cessation or reduction of airflow due to upper airway obstructions. These respiratory events lead to chronic sleep fragmentation and intermittent hypoxemia. Several studies have shown that OSA is associated with daytime sleepiness and cognitive dysfunctions, characterized by impairments of attention, episodic memory, working memory, and executive functions. This paper reviews the cognitive profile of adults with OSA and discusses the relative role of altered sleep and hypoxemia in the aetiology of these cognitive deficits. Markers of cognitive dysfunctions such as those measured with waking electroencephalography and neuroimaging are also presented. The effects of continuous positive airway pressure (CPAP) on cognitive functioning and the possibility of permanent brain damage associated with OSA are also discussed. Finally, this paper reviews the evidence suggesting that OSA is a risk factor for developing mild cognitive impairment and dementia in the aging population and stresses the importance of its early diagnosis and treatment.

The Relationships Between Poor Sleep Efficiency and Mild Cognitive Impairment in Parkinson Disease

BACKGROUND

Mild cognitive impairment (MCI) and sleep disturbances are common features in Parkinson disease (PD). This study sought to investigate whether patients with MCI in PD (PD-MCI) have more pronounced sleep disturbance compared to those without PD-MCI and whether phenotypic presentations differ according to the PD-MCI subtypes.

METHODS

A total of 95 patients with idiopathic PD (53 meeting criteria for PD-MCI and 42 who were not cognitively impaired) and 22 controls underwent neurological and neuropsychological examination. They wore actigraphy watches for 2 weeks, from which measures of nocturnal sleep efficiency were calculated.

RESULTS

Patients with PD-MCI has significantly poorer sleep efficiency compared to those without PD-MCI. This effect was particularly apparent in those with multiple-domain PD-MCI, compared to those with single-domain PD-MCI. Furthermore, patients in the PD-MCI group had significantly more nontremor features.

CONCLUSIONS

These data suggest that PD-MCI is associated with greater sleep disturbance and nontremor features of PD. This is further evidence for the potential role that sleep disturbance plays in the heterogeneity of PD.