Insomnia symptoms combined with nocturnal hypoxia associate with cardiovascular comorbidity in the European sleep apnea cohort (ESADA)

Sex and Sleep Disruption as Contributing Factors in Alzheimer's Disease

Alzheimer's disease (AD) affects more women than men, with women throughout the menopausal transition potentially being the most under researched and at-risk group. Sleep disruptions, which are an established risk factor for AD, increase in prevalence with normal aging and are exacerbated in women during menopause. Sex differences showing more disrupted sleep patterns and increased AD pathology in women and female animal models have been established in literature, with much emphasis placed on loss of circulating gonadal hormones with age. Interestingly, increases in gonadotropins such as follicle stimulating hormone are emerging to be a major contributor to AD pathogenesis and may also play a role in sleep disruption, perhaps in combination with other lesser studied hormones. Several sleep influencing regions of the brain appear to be affected early in AD progression and some may exhibit sexual dimorphisms that may contribute to increased sleep disruptions in women with age. Additionally, some of the most common sleep disorders, as well as multiple health conditions that impair sleep quality, are more prevalent and more severe in women. These conditions are often comorbid with AD and have bi-directional relationships that contribute synergistically to cognitive decline and neuropathology. The association during aging of increased sleep disruption and sleep disorders, dramatic hormonal changes during and after menopause, and increased AD pathology may be interacting and contributing factors that lead to the increased number of women living with AD.

Adaptive responses to chronic intermittent hypoxia: contributions from the European Sleep Apnoea Database (ESADA) Cohort

Obstructive sleep apnoea (OSA) is a common disease in the general population, and is associated with increased cardiovascular risk and several comorbidities. Obesity favours upper airway collapsibility, but other pathophysiological traits have been identified, i.e. upper airway muscle activity, modulation of the respiratory drive, and the arousal threshold. OSA causes chronic intermittent hypoxia, inflammatory activation and autonomic imbalance with diurnal and nocturnal sympathetic hyperactivity. Disentangling so many components to investigate the pathogenesis of OSA's consequences is very hard clinically. However, albeit imperfect, clinical medicine constitutes a major source of inspiration for basic research, and a mutual exchange of information is essential between clinicians and physiologists to improve our understanding of disease states. OSA is no exception, and this narrative review will summarize the results of clinical studies performed over the years by the European Sleep Apnoea Database (ESADA) Study Group, to explore the variables linked to markers of intermittent hypoxia as opposed to the traditional assessment of OSA severity based on the frequency of respiratory events during sleep (the Apnoea Hypopnoea Index). The results of the clinical studies indicate that intermittent hypoxia variables are associated with several comorbidities, although evidence of a cause-effect relationship is still missing in many cases. It is also possible that adaptive rather than maladaptive responses could be evoked by intermittent hypoxia. The intensity, duration and frequency of intermittent hypoxia episodes causing adaptive rather than maladaptive responses, and their clinical implications, deserve further investigation.

Co-morbid insomnia and sleep apnea (COMISA): recent research and future directions

PURPOSE OF REVIEW

Insomnia and obstructive sleep apnea have previously been viewed as completely independent conditions. However, there is now increasing recognition that insomnia and sleep apnea frequently co-occur. Co-morbid insomnia and sleep apnea (COMISA) is a highly prevalent condition that is associated with impairment of sleep, daytime function, mental health and physical health outcomes, and mortality risk. This review aims to provide an update on COMISA prevalence, consequences, treatment approaches, and future research directions.

RECENT FINDINGS

People with COMISA experience worse sleep, mental health, physical health, quality of life and longevity compared to people with neither condition, and often compared to those with insomnia alone and sleep apnea alone. Emerging evidence suggests that cognitive behavioral therapy for insomnia is an effective treatment in the presence of treated and untreated sleep apnea, that may also improve manifestations and subsequent management of sleep apnea. Future research is required to understand the etiology of COMISA, and to develop and implement tailored treatment approaches.

SUMMARY

It is important for sleep and respiratory technicians, researchers and clinicians to be aware of the high co-morbidity rates, consequences, and treatment requirements of patients with co-morbid insomnia and sleep apnea.

A nationwide study on the prevalence and contributing factors of obstructive sleep apnea in Iran

Reliable obstructive sleep apnea (OSA) prevalence information in Iran is lacking due to inconsistent local study results. To estimate OSA prevalence and identify clinical phenotypes, we conducted a nationally representative study using multi-stage random cluster sampling. We recruited 3198 individuals and extrapolated the results to the entire Iranian population using complex sample survey analyses. We identified 3 clinical phenotypes as "sleepy," "insomnia," and "restless legs syndrome (RLS)." The prevalence of OSA was 28.7% (95%CI: 26.8-30.6). The prevalence of "sleepy," "insomnia," and "RLS" phenotypes were 82.3%, 77.8%, and 36.5% in women, and 64.8%, 67.5%, and 17.9% in men, respectively. "Sleepy" and "insomnia" phenotypes overlapped the most. Age (OR: 1.9), male sex (OR: 3.8), BMI (OR: 1.13), neck circumference (OR: 1.3), RLS (OR: 2.0), and insomnia (OR: 2.3) were significant OSA predictors (p-values: 0.001). In men, "sleepy" phenotype was associated with youth and unmarried status but not in women. The "insomnia" phenotype was associated with shorter sleep duration in women; cardiovascular diseases (CVD), urban residency, and shorter sleep duration in men. "RLS" phenotype was associated with shorter sleep duration and CVD in women and older age, lower educational level, CVD, and hypertension in men. The findings point to the need for funding of OSA screening in Iran, for a different assessment of men and women, and for future sleep research to consider overlapping phenotypes.

Prevalence of risk and factors associated with obstructive sleep apnea-hypopnea syndrome in an adult population in Kinshasa, Democratic Republic of Congo

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is an underdiagnosed and lesser known disease in sub-Saharan Africa. We believe that this is the first descriptive and analytical cross-sectional study in Kinshasa (from February 1 to October 31, 2021), which included respondents aged ≥18 years. The study aimed to determine the prevalence of the risk and factors associated with OSAHS. Each participant signed a free and informed consent. Statistical analyses were performed using XLStat 2020 and the Statistical Package for the Social Sciences version 24 for Windows. Odds ratios (ORs) were calculated to determine the degree of association between these variables and a high risk of OSAHS. The significance threshold was p < 0.05 and confidence interval (CI) at 95%. There were 4,162 participants, including 2,287 men (54.9%), with an mean (SD) age of 32 ± 12.6 years. The prevalence of OSAS risk was 17.4% and 7.9% for men and women, respectively. The associated risk factors were male sex (OR 4, 95% CI 3.20-5.54), hypertension (OR 6.7, 95% CI 4.87-9.30), age ≥60 years (OR 8.7, 95% CI 4.07-18.88), obesity/overweight (OR 1.94, 95% CI 1.13-3.78), and excessive daytime sleepiness (OR 2.63, 95% CI 2.05-3.56). The risk of OSAS in Kinshasa is high and it increases with age, male sex, obesity, and hypertension. The Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and male Gender (STOP-BANG) questionnaire is an easy-to-use tool for diagnostic orientation.

A comprehensive evaluation of insomnia, obstructive sleep apnea and comorbid insomnia and obstructive sleep apnea in US military personnel

STUDY OBJECTIVES

The aim of this study was to characterize the sleep disorders of insomnia, obstructive sleep apnea (OSA), and comorbid insomnia and OSA (COMISA) in active duty military personnel.

METHODS

Prospective observational study of 309 military personnel with a mean age of 37.17 years (SD = 7.27). Participants served in four branches of the U.S. military (47.9% Air Force, 38.8% Army, 11.3% Navy, and 1.9% Marines). Sleep diagnoses were rendered after video-polysomnography and a clinical evaluation. Validated self-report measures assessed insomnia severity, excessive daytime sleepiness, sleep quality, disruptive nocturnal behaviors, nightmare disorder, shift work disorder (SWD), sleep impairment, fatigue, posttraumatic stress disorder (PTSD) symptoms, anxiety, depression, and traumatic brain injury (TBI). General linear models and Pearson chi-square tests were used for between-group differences in data analyses.

RESULTS

Insomnia was diagnosed in 32.7%, OSA in 30.4% and COMISA in 36.9%. Compared to military personnel with OSA alone, those with insomnia only and COMISA had significantly greater insomnia severity, disruptive nocturnal behaviors, sleep-related impairment, rates of nightmare disorder, and poorer sleep quality (all Ps < .05). They also reported greater symptoms of fatigue, PTSD, anxiety, and depression (all Ps < .05). There were no significant differences among the three sleep disorder diagnostic groups on sleepiness, SWD, or TBI.

CONCLUSIONS

Military personnel with insomnia only and COMISA overall report worsened symptoms of sleep disorders, sleep-related impairment, fatigue, and psychiatric disorders than those with OSA. Results highlight the importance of a comprehensive assessment for sleep-related impairment, sleep, and comorbid disorders in military personnel with clinically significant sleep disturbances.

Cancer sleep symptom-related phenotypic clustering differs across three cancer specific patient cohorts

Specific sleep disorders have been linked to disease progression in different cancers. We hypothesised sleep symptom clusters would differ between cancer types. The aim of this study was to compare sleep symptom clusters in post-treatment melanoma, breast and endometrial cancer patients. Data were collected from 124 breast cancer patients (1 male, 60 ± 15 years, 28.1 ± 6.6 kg/m² ), 82 endometrial cancer patients (64.0 ± 12.5 years, 33.5 ± 10.4 kg/m² ) and 112 melanoma patients (59 male, 65.0 ± 18.0 years, 29.1 ± 6.6 kg/m² ). All patients completed validated questionnaires to assess sleep symptoms, including the Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Functional Outcomes of Sleep Questionnaire-10 (FOSQ-10). Snoring, tiredness, observed apneas, age, BMI, and gender data were also collected. Binary values (PSQI, ISI, FOSQ), or continuous variables for sleepiness (ESS) and perceived sleep quality (PSQI), were created and sleep symptom clusters were identified and compared across cancer cohorts. Four distinct sleep symptom clusters were identified: minimally symptomatic (n = 152, 47.7%); insomnia-predominant (n = 87, 24.9%); very sleepy with upper airway symptoms (n = 51, 16.3%), and severely symptomatic with severe dysfunction (n = 34, 11.1%). Breast cancer patients were significantly more likely to be in the insomnia predominant or severely symptomatic with severe dysfunction clusters, whereas melanoma patients were more likely to be minimally symptomatic or sleepy with upper airway symptoms (p <0.0001). Endometrial cancer patients were equally distributed across symptom clusters. Sleep symptom clusters vary across cancer patients. A more personalised approach to the management of sleep-related symptoms in these patients may improve the long term quality of life and survival.

Cluster-derived obstructive sleep apnea phenotypes and outcomes at 5-year follow-up

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is a heterogeneous, complex disease. We aimed to identify OSA phenotypes through cluster analysis and to perform a long-term follow-up to validate the phenotypes.

METHODS

We applied a partitioning around medioids technique in a cohort of 1,217 participants recently diagnosed with OSA. We performed a 5-year follow-up analyzing the incidence of comorbidities, chronic medication, hospital admissions, mortality, and the influence of continuous positive airway pressure treatment on mortality risk.

RESULTS

We identified three phenotypes: two predominantly male clusters, one composed of middle-aged participants with overweight, moderate OSA, and cardiovascular risk factors and the other consisting of older, obese participants with severe OSA, cardiovascular risk factors, ischemic heart disease (18.4%), and atrial fibrillation (9.7%). The third cluster was composed of 77% female participants with moderate OSA; cardiovascular risk factors; the highest prevalence of depression (15.7%); and high prescription of antidepressants (55.1%), anxiolytics (40.0%), hypnotics, sedatives (11.1%), nonsteroidal anti-inflammatory drugs (67.9%), and weak opioids (15.1%). The baseline characteristics of each cluster maintained the same trend over time regarding the incidence of new comorbidities, medication intake, hospitalization rates, and reasons for admission. The absence of continuous positive airway pressure treatment was associated with a significantly higher risk of all-cause mortality (hazard ratio 5.84, confidence interval 2.9-11.8), especially in the older men (hazard ratio 7.7, confidence interval 4.06-14.63) and predominantly female clusters (hazard ratio 2.79, confidence interval 1.34-5.79).

CONCLUSIONS

We identified three phenotypes with relevant clinical and prognostic implications in order to improve personalized strategies in OSA management.

CITATION

Silveira MG, Sampol G, Mota-Foix M, Ferrer J, Lloberes P. Cluster-derived obstructive sleep apnea phenotypes and outcomes at 5-year follow-up. J Clin Sleep Med. 2022;18(2):597-607.

Influence of nocturnal insomnia symptoms on obstructive sleep apnea diagnosis in a clinical referral cohort

STUDY OBJECTIVES

To assess whether nocturnal symptoms of insomnia influence the prevalence of obstructive sleep apnea (OSA) in a clinical referral cohort.

METHODS

Insomnia was defined by the presence of one or more of the following complaints: difficulty initiating sleep, difficulty maintaining sleep, and/or early morning awakenings. OSA severity was based on an apnea-hypopnea index: ≥ 5.0/h (any OSA), ≥ 15.0/h (moderate/severe OSA), and ≥ 30/h (severe OSA). Multivariate logistic regression analysis was used to evaluate predictive factors for OSA diagnosis and severity.

RESULTS

Overall, 12,021 outpatients referred for polysomnography (PSG) were grouped into two cohorts: without insomnia (58.2%) and with insomnia (41.8%). Individuals without insomnia had a higher prevalence of OSA than those with insomnia (p < 0.001, for all OSA severity levels). The presence of insomnia was negatively associated with diagnosis of any OSA (adjusted odds ratio [OR]: 0.852; 95% confidence interval [CI]: 0.769-0.944), moderate/severe OSA (adjusted OR: 0.819; 95% CI: 0.751-0.892), and severe OSA (adjusted OR: 0.816; 95% CI: 0.746-0.892). Moreover, the number of nocturnal symptoms of insomnia was associated with a lower likelihood of OSA, even when adjusted for other confounders such as sex, age, body mass index, neck circumference, excessive daytime sleepiness, hypertension, and type 2 diabetes mellitus.

CONCLUSIONS

In this present study that included a large sample of consecutive outpatients, there was an inverse relationship between the number of nocturnal symptoms of insomnia and OSA diagnosis.

Characteristics of Patients with Obstructive Sleep Apnea at High Risk for Cardiovascular Disease

Background and Objectives: To evaluate the influence of obstructive sleep apnea (OSA)-related symptoms on prevalent cardiovascular disease (CVD) in a large clinical population of patients. Materials and Methods: A total of 2127 patients (mean age 55 years, 24% women) underwent diagnostic polysomnography and were evaluated using the Epworth sleepiness scale (ESS), the Athens Insomnia Scale (AIS), and the Beck Depression Inventory (BDI). We investigated the predictive value of OSA-associated symptoms for prevalent cardiovascular disease, after adjustment for relevant confounding factors including age, obesity, and co-morbidities. Results: Patients with OSA and CVD were older and had a higher Body Mass Index (BMI); the percentage of obese patients was also higher (83% vs. 70%, p < 0001). They also had greater neck, waist, and hip circumferences and a higher waist-to-hip ratio. Excessive daytime sleepiness (ESS ≥ 10) [odds ratio (95% CI) 1.112 (0.708–1.748), p = 0.64], insomnia symptoms (AIS ≥ 6) [odds ratio (95% CI) 0.748 (0.473–1.184), p = 0.21], frequent awakenings [odds ratio (95% CI) 1.599 (1.019–2.508), p = 0.06], and nocturia [odds ratio (95% CI) 1.359 (0.919–2.009), p = 0.124] were not associated with CVD after adjustment for the previous confounders. On the other hand, depressive symptoms (BDI ≥ 10) independently predicted prevalent CVD [odds ratio (95% CI) 1.476 (1.154–1.887), p = 0.002]. Further analysis in subgroups stratified by age, BMI, and gender demonstrated that depressive symptoms predicted prevalent CVD but only in the subgroup of younger (age group < 60 years), obese (BMI group ≥ 30), and male (OR = 1.959, 95% CI = 1.209–3.175, p = 0.006) OSA patients. Conclusions: OSA patients with CVD were more likely to complain of less typical OSA symptoms and depressive symptoms compared to patients without CVD in this large clinical patient cohort, supportingthecomplexity and heterogeneityof OSA.

Network pharmacology-based and molecular docking prediction of the active ingredients and mechanism of ZaoRenDiHuang capsules for application in insomnia treatment

BACKGROUND

The ZaoRenDiHuang (ZRDH) capsule is widely used in clinical practice and has significant therapeutic effects on insomnia. However, its active ingredients and mechanisms of action for insomnia remain unknown. In this study, network pharmacology was employed to elucidate the potential anti-insomnia mechanisms of ZRDH.

METHODS

The potential active ingredients of ZRDH were obtained from the Traditional Chinese Medicine Systems Pharmacology Database. Possible targets were predicted using SwissTargetPrediction tools. The insomnia-related targets were identified using the therapeutic target database, Drugbank database, Online Mendelian Inheritance in Man database, and gene-disease associations database. A compound-target-disease network was constructed using Cytoscape for visualization. Additionally, the protein functional annotation and identification of signaling pathways of potential targets were performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses using the Metascape platform.

RESULTS

In this study, 61 anti-insomnia components and 65 anti-insomnia targets of ZRDH were filtered through database mining. The drug-disease network was constructed with five key components. Sixty-five key targets were identified using topological analysis. Docking studies indicated that bioactive compounds could stably bind to the pockets of target proteins. Through data mining and network analysis, the GO terms and KEGG annotation suggested that the neuroactive ligand-receptor interaction, serotonergic synapse CAMP signaling, HIF-1a signaling, and toll-like receptor signaling pathways play vital roles against insomnia.

CONCLUSION

The potential mechanisms of ZRDH treatment for insomnia involve multiple components, targets, and pathways. These findings provide a reference for further investigations into the mechanisms underlying ZRDH treatment of insomnia.

Insomnia disorder: clinical and research challenges for the 21st century

BACKGROUND AND PURPOSE

Insomnia is a common and debilitating disorder that is frequently associated with important consequences for physical health and well-being.

METHODS

An international expert group considered the current state of knowledge based on the most relevant publications in the previous 5 years, discussed the current challenges in the field of insomnia and identified future priorities.

RESULTS

The association of trajectories of insomnia with subsequent quality of life, health and mortality should be investigated in large populations. Prospective health economics studies by separating the costs driven specifically by insomnia and costs attributable to its long-term effects are needed. Ignoring the heterogeneity of insomnia patients leads to inadequate diagnosis and inefficient treatment. Individualized interventions should be promoted. More data are needed on both the impact of sleep on overnight effects, such as emotion regulation, and the potential compensatory effort to counteract diurnal impairments. Another gap is the definition of neurocognitive deficits in insomnia patients compared to normal subjects after chronic sleep loss. There are also a number of key gaps related to insomnia treatment. Expert guidelines indicate cognitive-behavioural therapy for insomnia as first-line treatment. They neglect, however, the reality of major healthcare providers. The role of combined therapy, cognitive-behavioural therapy for insomnia plus pharmacological treatment, should be evaluated more extensively.

CONCLUSION

Whilst insomnia disorder might affect large proportions of the population, there are a number of significant gaps in the epidemiological/clinical/research studies carried out to date. In particular, the identification of different insomnia phenotypes could allow more cost-effective and efficient therapies.

Evaluation of a multicomponent grading system for obstructive sleep apnoea: the Baveno classification

New findings on pathophysiology, epidemiology, and outcome have raised concerns on the relevance of the apnoea-hypopnoea index (AHI) in the classification of obstructive sleep apnoea (OSA) severity. Recently, a multicomponent grading system decision integrating symptomatology and comorbidities (Baveno classification), was proposed to characterise OSA and to guide therapeutic decisions. We evaluated whether this system reflects the OSA population, whether it translates into differences in outcomes, and whether the addition of AHI improves the scheme. A total of 14 499 OSA patients from the European Sleep Apnoea Database cohort were analysed. The groups were homogeneously distributed and were found to clearly stratify the population with respect to baseline parameters. Differences in sleepiness and blood pressure between the groups were analysed in a subgroup of patients after 24-36 months of treatment. Group A (minor symptoms and comorbidities) did not demonstrate any effect of treatment on outcome. However, groups B (severe symptoms, minor comorbidities), C (minor symptoms, severe comorbidities) and D (severe symptoms and comorbidities) were associated with improvement in either or both parameters with treatment. The AHI is an essential prerequisite of the diagnosis; however, adding the AHI did not improve the classification. Rather, it was inferior with respect to guiding the treatment decision. Thus, the Baveno classification allows a better stratification of the OSA population and may provide a better guidance for therapeutic decisions in OSA.

The Importance of Sleep Fragmentation on the Hemodynamic Dipping in Obstructive Sleep Apnea Patients

Introduction

Obstructive sleep apnea (OSA) has been associated with non-dipping blood pressure (BP). The precise mechanism is still under investigation, but repetitive oxygen desaturation and arousal induced sleep fragmentation are considered the main contributors.

Methods

We analyzed beat-to-beat measurements of hemodynamic parameters (HPs) during a 25-min period of wake–sleep transition. Differences in the mean HP values for heart rate (HR), systolic BP (SBP), and stroke volume (SV) during wake and sleep and their standard deviations (SDs) were compared between 34 controls (C) and 22 OSA patients. The Student’s t-test for independent samples and the effect size by Cohen’s d (d) were calculated. HP evolution was investigated by plotting the measured HP values against each consecutive pulse wave. After a simple regression analysis, the calculated coefficient beta (SCB) was used to indicate the HP evolution. We furthermore explored by a hierarchical block regression which variables increased the prediction for the SCB: model 1 BMI and age, model 2 + apnea/hypopnea index (AHI), and model 3 + arousal index (AI).

Results

Between the two groups, the SBP increased in OSA and decreased in C resulting in a significant difference (p = 0.001; d = 0.92). The SV demonstrated a similar development (p = 0.047; d = 0.56). The wake/sleep variation of the HP measured by the SD was higher in the OSA group—HR: p < 0.001; d = 1.2; SBP: p = 0.001; d = 0.94; and SV: p = 0.005; d = 0.82. The hierarchical regression analysis of the SCB demonstrated in SBP that the addition of AI to AHI resulted in ΔR²: +0.163 and ΔF + 13.257 (p = 0.001) and for SV ΔR²: +0.07 and ΔF 4.83 (p = 0.003). The AI but not the AHI remained statistically significant in the regression analysis model 3—SBP: β = 0.717, p = 0.001; SV: β = 0.469, p = 0.033.

Conclusion

In this study, we demonstrated that in OSA, the physiological dipping in SBP and SV decreased, and the variation of all investigated parameters increased. Hierarchical regression analysis indicates that the addition of the AI to BMI, age, and AHI increases the prediction of the HP evolution following sleep onset for both SBP and SV and may be the most important variable.