Sleep remains disturbed in patients with obstructive sleep apnea treated with positive airway pressure: a three-month cohort study using continuous actigraphy

Obstructive sleep apnea may induce sleep-wake cycle dysregulation: An actigraphic study

Obstructive sleep apnea (OSA) causes sleep fragmentation and excessive daytime sleepiness (EDS). OSA has been hypothesised to impair the circadian sleep-wake rhythm, and this dysregulation may in turn exacerbate OSA-related diurnal symptoms. Hence, this study aimed to assess the sleep-wake rhythm through actigraphy, and its relationship with EDS in patients with untreated OSA. Patients with moderate-severe OSA (apnea-hypopnea index ≥15/h) and healthy controls (HC) underwent a 7-day actigraphic recording to evaluate the sleep-wake rhythm. Participants underwent a sleep medicine visit and completed the self-report questionnaires assessing EDS (Epworth sleepiness scale, ESS), sleep quality (Pittsburgh sleep quality index, PSQI), and chronotype (morningness-eveningness questionnaire, MEQ). This study included 48 OSA patients (72.9% males; mean age 56.48 ± 9.53 years), and 22 HC (45.5% males; mean age 53.73 ± 18.20 years). After controlling for MEQ scores, actigraphic recording showed that the OSA patients present a lower sleep time (p = 0.011) and sleep efficiency (p = 0.013), as well as a higher sleep latency (p = 0.047), and sleep fragmentation (p = 0.029) than the HC. Regarding the sleep-wake rhythm actigraphic parameters, the OSA patients showed a lower average activity during the most active 10-hour period (p = 0.036) and a lower day/night activity ratio (p = 0.007) than the HC. Patients with OSA also reported higher ESS (p = 0.005) and PSQI scores (p < 0.001), and a chronotype less of morning type (p = 0.027) than the HC. In conclusion, this study documented a reduced diurnal motor activity and lower day/night activity ratio in OSA patients than in controls. These findings suggest a dysregulation of the circadian sleep-wake rhythm in OSA, possibly related to both EDS and reduced daytime motor activity.

Same sleep disorder but different sleep patterns: individual differences in sleep health and depressive symptomatology in veterans with obstructive sleep apnea

PURPOSE

Poor sleep health, a composite measure of key sleep characteristics, may relate to increased depressive symptoms among individuals treated for obstructive sleep apnea. The current investigation examined the association between sleep health and depressive symptomatology.

METHODS

In a pilot sample of 13 symptomatic OSA military Veterans with adequate CPAP adherence (mean age = 54.8, 76.9% male, 100% White), empirically validated cutoffs were applied to actigraphy-derived sleep variables: duration, efficiency, timing, and regularity.

RESULTS

Participants with zero optimal sleep scores had significantly higher depressive scores (M = 19.0, SD = 3.0) than participants with 1 or 2 (M = 9.8. SD = 4.3, p = .016) and 3 or more optimal sleep scores (M = 11.3, SD = 4.9, p = .038).

CONCLUSIONS

These preliminary findings suggest that better sleep health was associated with lower depressive symptomatology. Future work should replicate these preliminary findings in a larger sample.

Multi-night home assessment of sleep structure in OSA with and without insomnia

OBJECTIVE

To explore sleep structure in participants with obstructive sleep apnea (OSA) and comorbid insomnia (COMISA) and participants with OSA without insomnia (OSA-only) using both single-night polysomnography and multi-night wrist-worn photoplethysmography/accelerometry.

METHODS

Multi-night 4-class sleep-staging was performed with a validated algorithm based on actigraphy and heart rate variability, in 67 COMISA (23 women, median age: 51 years) and 50 OSA-only (15 women, median age: 51) participants. Sleep statistics were compared using linear regression models and mixed-effects models. Multi-night variability was explored using a clustering approach and between- and within-participant analysis.

RESULTS

Polysomnographic parameters showed no significant group differences. Multi-night measurements, during 13.4 ± 5.2 nights per subject, demonstrated a longer sleep onset latency and lower sleep efficiency for the COMISA group. Detailed analysis of wake parameters revealed longer mean durations of awakenings in COMISA, as well as higher numbers of awakenings lasting 5 min and longer (WKN≥5min) and longer wake after sleep onset containing only awakenings of 5 min or longer. Within-participant variance was significantly larger in COMISA for sleep onset latency, sleep efficiency, mean duration of awakenings and WKN≥5min. Unsupervised clustering uncovered three clusters; participants with consistently high values for at least one of the wake parameters, participants with consistently low values, and participants displaying higher variability.

CONCLUSION

Patients with COMISA more often showed extended, and more variable periods of wakefulness. These observations were not discernible using single night polysomnography, highlighting the relevance of multi-night measurements to assess characteristics indicative for insomnia.

Guidelines for the assessment and management of residual sleepiness in obstructive apnea-hypopnea syndrome: Endorsed by the French Sleep Research and Medicine Society (SFRMS) and the French Speaking Society of Respiratory Diseases (SPLF)

Excessive daytime sleepiness (EDS) is frequent among patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and can persist despite the optimal correction of respiratory events (apnea, hypopnea and respiratory efforts), using continuous positive airway pressure (CPAP) or mandibular advancement device. Symptoms like apathy and fatigue may be mistaken for EDS. In addition, EDS has multi-factorial origin, which makes its evaluation complex. The marketing authorization [Autorisation de Mise sur le Marché (AMM)] for two wake-promoting agents (solriamfetol and pitolisant) raises several practical issues for clinicians. This consensus paper presents recommendations of good clinical practice to identify and evaluate EDS in this context, and to manage and follow-up the patients. It was conducted under the mandate of the French Societies for sleep medicine and for pneumology [Société Française de Recherche et de Médecine du Sommeil (SFRMS) and Société de Pneumologie de Langue Française (SPLF)]. A management algorithm is suggested, as well as a list of conditions during which the patient should be referred to a sleep center or a sleep specialist. The benefit/risk balance of a wake-promoting drug in residual EDS in OSAHS patients must be regularly reevaluated, especially in elderly patients with increased cardiovascular and psychiatric disorders risks. This consensus is based on the scientific knowledge at the time of the publication and may be revised according to their evolution.

Is obstructive sleep apnea a circadian rhythm disorder?

Obstructive sleep apnea is the most common sleep-related breathing disorder worldwide and remains underdiagnosed. Its multiple associated comorbidities contribute to a decreased quality of life and work performance as well as an increased risk of death. Standard treatment seems to have limited effects on cardiovascular and metabolic aspects of the disease, emphasising the need for early diagnosis and additional therapeutic approaches. Recent evidence suggests that the dysregulation of circadian rhythms, processes with endogenous rhythmicity that are adjusted to the environment through various cues, is involved in the pathogenesis of comorbidities. In patients with obstructive sleep apnea, altered circadian gene expression patterns have been demonstrated. Obstructive respiratory events may promote circadian dysregulation through the effects of sleep disturbance and intermittent hypoxia, with subsequent inflammation and disruption of neural and hormonal homeostasis. In this review, current knowledge on obstructive sleep apnea, circadian rhythm regulation, and circadian rhythm sleep disorders is summarised. Studies that connect obstructive sleep apnea to circadian rhythm abnormalities are critically evaluated. Furthermore, pathogenetic mechanisms that may underlie this association, most notably hypoxia signalling, are presented. A bidirectional relationship between obstructive sleep apnea and circadian rhythm dysregulation is proposed. Approaching obstructive sleep apnea as a circadian rhythm disorder may prove beneficial for the development of new, personalised diagnostic, therapeutic and prognostic tools. However, further studies are needed before the clinical approach to obstructive sleep apnea includes targeting the circadian system.

Investigation and management of residual sleepiness in CPAP-treated patients with obstructive sleep apnoea: the European view

Excessive daytime sleepiness (EDS) is a major symptom of obstructive sleep apnoea (OSA), defined as the inability to stay awake during the day. Its clinical descriptors remain elusive, and the pathogenesis is complex, with disorders such as insufficient sleep and depression commonly associated. Subjective EDS can be evaluated using the Epworth Sleepiness Scale, in which the patient reports the probability of dozing in certain situations; however, its reliability has been challenged. Objective tests such as the multiple sleep latency test or the maintenance of wakefulness test are not commonly used in patients with OSA, since they require nocturnal polysomnography, daytime testing and are expensive. Drugs for EDS are available in the United States but were discontinued in Europe some time ago. For European respiratory physicians, treatment of EDS with medication is new and they may lack experience in pharmacological treatment of EDS, while novel wake-promoting drugs have been recently developed and approved for clinical use in OSA patients in the USA and Europe. This review will discuss 1) the potential prognostic significance of EDS in OSA patients at diagnosis, 2) the prevalence and predictors of residual EDS in treated OSA patients, and 3) the evolution of therapy for EDS specifically for Europe.

The role of circadian rhythms in Obstructive Sleep Apnea symptoms and novel targets for treatment

Obstructive Sleep Apnea (OSA) is a common disorder that is associated with disability, premature mortality and lost quality of life. Excessive daytime sleepiness and depressive symptoms confer a great portion of the disability and lost quality of life associated with the disorder. While showing robust rates of response and symptoms resolutions, current treatments aimed at correcting the respiratory disturbances are not universally successful and a non-negligible proportion of patients who are correctly using available therapies do not experience symptomatic relief, suggesting that mechanisms beyond the respiratory disturbances may be involved in the pathogenesis of symptoms. A growing body of literature concerning animal and human models suggests that the sleep and respiratory disturbances commonly seen in OSA, namely sleep fragmentation, partial sleep deprivation, intermittent hypoxia, can promote shifts in circadian rhythms ultimately leading to misalignment between sleep-wake rhythms and the internal clock, as well as desynchrony amongst peripheral clocks and peripheral and central clock. This manuscript reviews the current evidence in support of a circadian disturbance underlying OSA symptomatology and proposes new applications for existing chronotherapeutic interventions with the potential for improving symptoms and quality of life for those patients that do not find symptomatic relief with currently available treatments.

Accuracy of Actigraphy Compared to Concomitant Ambulatory Polysomnography in Narcolepsy and Other Sleep Disorders

Actigraphy provides longitudinal sleep data over multiple nights. It is a less expensive and less cumbersome method for measuring sleep than polysomnography. Studies assessing accuracy of actigraphy compared to ambulatory polysomnography in different sleep-disordered patients are rare. We aimed to compare the concordance between these methods in clinical setting. We included 290 clinical measurements of 281 sleep laboratory patients (mean age 37.9 years, 182 female). Concomitant ambulatory polysomnography and actigraphy were analyzed to determine the agreement in patients with obstructive sleep apnea, narcolepsy, periodic leg movement disorder, hypersomnia, other rarer sleep disorders, or no organic sleep disorder. Bland-Altman plots showed excellent accuracy, but poor precision in single night results between the two methods in the measurement of sleep time, sleep efficiency, and sleep latency. On average, actigraphy tended to overestimate sleep time by a negligible amount, −0.13 min, 95% confidence interval [−5.9, 5.6] min in the whole sample. Overestimation was largest, −12.8 [−25.1, −0.9] min, in patients with obstructive sleep apnea. By contrast, in patients with narcolepsy, actigraphy tended to underestimate sleep time by 24.3 [12.4, 36.1] min. As for sleep efficiency, actigraphy underestimated it by 0.18 [−0.99, 1.35] % and sleep latency by 11.0 [8.5, 13.6] min compared to polysomnography. We conclude that, in measuring sleep time, actigraphy is reasonably reliable and helpful to be used for a week or two to exclude insufficient sleep in patients with the suspicion of narcolepsy. However, the effectiveness of actigraphy in determining sleep seems to decrease in subjects with low sleep efficiencies.

Psychological distress in patients with obstructive sleep apnoea: The role of hostility and coping self-efficacy

We aimed to assess whether hostility and coping self-efficacy are associated with psychological distress in obstructive sleep apnoea patients. Furthermore, we examined whether coping self-efficacy mediates the association between hostility and psychological distress. We included 150 obstructive sleep apnoea patients (Apnoea-Hypopnoea Index ⩾5; 68% male; mean age: 48.9 ± 9.5 years). Regression models showed that hostility and poor coping self-efficacy were strongly associated with psychological distress in obstructive sleep apnoea patients. All assessed coping self-efficacy dimensions mediated the association between hostility and psychological distress. Coping self-efficacy for stopping unpleasant emotions and thoughts showed the strongest association with a lower level of psychological distress.

Social support, mastery, sleep-related problems and their association with functional status in untreated obstructive sleep apnoea patients

BACKGROUND

Social support and mastery are important aspects in the treatment of chronic diseases, however their role in connection with Obstructive Sleep Apnoea (OSA) remains unclear.

OBJECTIVES

The study examined the associations between social support, mastery, sleep-related problems and functional status in untreated OSA patients.

METHODS

All patients in this cross-sectional study completed the Multidimensional Scale of Perceived Social Support, the Pearlin Mastery Scale, the Pittsburgh Sleep Quality Index, the Epworth Sleepiness Scale and the Functional Outcomes of Sleep Questionnaire. Multiple linear regression and mediation analyses were used to analyse the data.

RESULTS

Participants were 150 newly diagnosed OSA patients (Apnoea-Hypopnoea Index-AHI≥5; 68% male; mean age 48.9 ± 9.5years). Compared with social support, mastery was more strongly associated with functional status. The indirect effects of sleep-related problems on functional status via mastery varied between 17.7% and 23.3%.

CONCLUSIONS

Supporting OSA patients' sense of mastery may significantly contribute to better disease management.

Executive and Visuospatial Dysfunction in Patients With Primary Restless Legs Syndrome/Willis-Ekbom Disease: Study of a Chinese Population

STUDY OBJECTIVES

The aim of the study was to investigate the cognitive function of patients with primary restless legs syndrome/Willis-Ekbom disease (RLS/ WED) in a Chinese population.

METHODS

A total of 40 patients with RLS/WED who were drug naïve and 40 controls, matched by age, sex, and educational level, were evaluated by cognitive function assessments, including the Chinese version of the Mini-Mental State Examination (MMSE-C), clock drawing test (CDT), Auditory Verbal Learning Test (AVLT), Rey-Osterrieth Complex Figure Test (CFT), and Stroop Color Word Test (SCWT).

RESULTS

Patients with RLS/WED showed worse performance on the SCWT (Stroop Card C time: 102.36 ± 17.12 versus 87.08 ± 7.73 seconds, P = .033; Interference Index: 3.39 ± 0.38 versus 2.90 ± 0.15, P < .0001), CFT (24.05 ± 9.28 versus 33.74 ± 1.59, P = .008), and CDT than controls (16-score method: 10.13 ± 3.94 versus 13.98 ± 1.79, P = .0002) after adjusting for Hamilton Anxiety Scale score, Hamilton Depression Scale score, Epworth Sleepiness Scale score, and Pittsburgh Sleep Quality Index total score to eliminate the confounders of concomitant sleep disturbances, anxiety, and depression.

CONCLUSIONS

Our study suggested that cognitive functions involving executive and visuospatial domains might be disturbed in Chinese patients with primary RLS/WED.

Effects of Actigraphically Acquired Sleep Quality on Driving Outcomes in Obstructive Sleep Apnea Patients and Control Drivers: A Naturalistic Study

We examined the effects of sleep quality on next day driving outcomes in a 3.5-month naturalistic driving study of 67 OSA and 47 matched control drivers. Sleep quality measures included total sleep time and sleep fragmentation from actigraphy. The driving outcomes included average speed, lateral control, longitudinal control, distraction, attention to driving- and non-driving related tasks. Sleep quality affected next day's driving performance differently for OSA and control drivers. Better sleep quality was associated with better lateral and longitudinal control during highway driving for control drivers. The reverse was true for OSA drivers. Similar effects were also seen in terms of distractions and attention to the driving task. These effects suggest improved sleep leads to greater risky driving and 'activation' among OSA drivers. Collectively, the findings suggest investment in long-term monitoring of sleep quality in commercial vehicle drivers both with and without sleep disorders may help manage safety risks.

Sleep-Disordered Breathing and Excessive Daytime Sleepiness

Sleep-related breathing disorders include obstructive sleep apnea (OSA), central sleep apnea, sleep-related hypoventilation, and sleep-related hypoxemia. Excessive daytime sleepiness (EDS) is frequently reported by patients with OSA but is not invariably present. The efficacy of positive airway pressure therapy in improving EDS is well established for OSA, but effectiveness is limited by suboptimal adherence. Non-OSA causes of sleepiness should be identified and treated before initiating pharmacotherapy for persistent sleepiness despite adequately treated OSA. Further research on the identification of factors that promote EDS in the setting of OSA is needed to aid in the development of better treatment options.