Effect of phrenic nerve stimulation on patients with central sleep apnea: A meta-analysis.

Patients with central sleep apnea (CSA) have a lower quality of life and higher morbidity and mortality. Phrenic nerve stimulation (PNS) is a novel treatment for CSA that has been shown to be safe. However, the effects of PNS on sleep changes are still under debate. This meta-analysis was performed to evaluate the efficacy of PNS in patients with CSA. PubMed, Scopus, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL) and Web of Science databases were searched for relevant studies published. We performed random-effects meta-analyses of the changes in apnea-hypopnea index (AHI), central apnea index (CAI), Arousal Index, percent of sleep with O2 saturation <90% (T90), Epworth Sleepiness Scale (ESS) and sleep efficiency. Ten studies with a total of 580 subjects were analyzed. Overall meta-analysis showed AHI [SMD: -2.24, 95% confidence interval (CI): was -3.11 to -1.36(p＜0.00001)], CAI [SMD: -2.32, 95% CI: -3.17 to -1.47 (p＜0.00001)] and Arousal Index (p = 0.0002, SMD (95% CI) -1.79 (-2.74 to -0.85)) significantly reduced after PNS. No significant changes were observed in T90, ESS and sleep efficiency (p > 0.05). Meta-analysis of observational studies demonstrated AHI, CAI and Arousal Index had a decreasing trend between before and after PNS (all, p＜0.05). However, ESS and T90 did not change significantly after PNS (p > 0.05). Meta-analysis of RCTs showed that CSA patients had trends of a lower AHI (I2 = 0%), CAI (I2 = 74%), Arousal Index (I2 = 0%), T90 (I2 = 0%) and ESS (I2 = 0%) after PNS (all, p＜0.05). The use of PNS appears to be safe and feasible in patients with CSA. However, larger, independent RCTs are required to investigate the efficacy and long-term effect of PNS and more attention should be paid to T90 and ESS.

Comparative study of the SleepImage ring device and polysomnography for diagnosing obstructive sleep apnea.

Purpose We aim to evaluate the diagnostic performance of the SleepImage Ring device in identifying obstructive sleep apnea (OSA) across different severity in comparison to standard polysomnography (PSG). Methods Thirty-nine patients (mean age, 56.8 ± 15.0 years; 29 [74.3%] males) were measured with the SleepImage Ring and PSG study simultaneously in order to evaluate the diagnostic performance of the SleepImage device for diagnosing OSA. Variables such as sensitivity, specificity, positive and negative likelihood ratio, positive and negative predictive value, and accuracy were calculated with PSG-AHI thresholds of 5, 15, and 30 events/h. Receiver operating characteristic curves were also built according to the above PSG-AHI thresholds. In addition, we analyzed the correlation and agreement between the apnea-hypopnea index (AHI) obtained from the two measurement devices. Results There was a strong correlation (r = 0.89, P < 0.001 and high agreement in AHI between the SleepImage Ring and standard PSG. Also, the SleepImage Ring showed reliable diagnostic capability, with areas under the receiver operating characteristic curve of 1.00 (95% CI, 0.91, 1.00), 0.90 (95% CI, 0.77, 0.97), and 0.98 (95% CI, 0.88, 1.000) for corresponding PSG-AHI of 5, 15 and 30 events/h, respectively. Conclusion The SleepImage Ring could be a clinically reliable and cheaper alternative to the gold standard PSG when aiming to diagnose OSA in adults. Supplementary Information: The online version contains supplementary material available at 10.1007/s13534-023-00304-9.

Neurocognitive functioning in comorbid insomnia and sleep apnea patients is better after positive airway pressure therapy, but worse after cognitive behavioral therapy for insomnia: exploratory analysis of cognitive outcomes from the Multidisciplinary Approach to the Treatment of Insomnia and Comorbid Sleep Apnea study.

STUDY OBJECTIVES: Neurocognitive impairments in comorbid insomnia and sleep apnea (COMISA) are not well documented. We explored neurocognitive functioning and treatment effects in individuals with COMISA as an ancillary study to a randomized clinical trial. METHODS: Participants with COMISA (n = 45; 51.1% female; mean age = 52.07 ± 13.29 years), from a 3-arm randomized clinical trial combining cognitive behavioral therapy for insomnia (CBT-I) and positive airway pressure (PAP) concurrently (CBT-I+PAP) or sequentially, completed neurocognitive testing at baseline, and post-treatment. Using Bayesian linear mixed models, we estimated effects of CBT-I, PAP, or CBT-I+PAP, compared to baseline, and CBT-I+PAP compared to PAP on 12 metrics across five cognitive domains. RESULTS: This COMISA sample had worse neurocognitive performance at baseline than reported for insomnia, sleep apnea, and controls in the literature, though short-term memory and psychomotor speed performance appears intact. When comparing PAP to baseline, performance on all measures was better after treatment. Performance after CBT-I was worse compared to baseline, and only performance in attention/vigilance, executive functioning via Stroop interference and verbal memory was better with moderate-high effect sizes and moderate probability of superiority (61-83). Comparisons of CBT-I+PAP to baseline generated results similar to PAP and comparing CBT-I+PAP to PAP revealed superior performance in only attention/vigilance via psychomotor vigilance task lapses and verbal memory for PAP. CONCLUSIONS: Treatment combinations involving CBT-I were associated with poorer neurocognitive performance. These potentially temporary effects may stem from sleep restriction, a component of CBT-I often accompanied by initially reduced total sleep time. Future studies should examine long-term effects of individual and combined COMISA treatment pathways to inform treatment recommendations. CLINICAL TRIAL: This was an ancillary study from a clinical trial (Multidisciplinary Approach to the Treatment of Insomnia and Comorbid Sleep Apnea (MATRICS), which was preregistered at www.clinicaltrials.gov (NCT01785303)).

Effects of sacubitril-valsartan on central and obstructive apneas in heart failure patients with reduced ejection fraction.

OBJECTIVE: This study aimed to evaluate the effect of sacubitril-valsartan (SV) on central apneas (CA) and obstructive apneas (OA) in patients with heart failure with reduced ejection fraction (HFrEF). METHODS: In patients with HFrEF, SV initiation was titrated to the highest tolerable dosage. Patients were evaluated with portable apnea monitoring, echocardiography, and cardiopulmonary exercise testing at baseline and 3 months later. RESULTS: Of a total of 18 patients, 9 (50%) had OA, 7 (39%) had CA, and 2 (11%) had normal breathing. SV therapy was related to a reduction in NT-pro BNP and an improvement in LV function after 3 months. Portable apnea monitoring revealed a significant decrease of the respiratory event index (REI) after treatment with SV (20 ± 23 events/h to 7 ± 7 events/h, p = 0.003). When subgrouping according to type of apneas, REI, and time spent below 90% saturation (T90) decreased in patients with CA and OA (all p < 0.05). CONCLUSION: In this prospective study, SV treatment for 3 months in patients with CA and OA is associated with a significant decrease in REI.

Daytime sleepiness is associated with increased coronary plaque burden among patients with obstructive sleep apnea.

PURPOSE: To investigate the cross-sectional associations of daytime sleepiness with coronary plaque volume and composition in patients with obstructive sleep apnea (OSA), and whether or not these associations are modified by age, gender, and obesity. METHODS: Patients who were confirmed with OSA through respiratory polygraphy and also underwent coronary CTA at a tertiary hospital were consecutively enrolled. The interval between the sleep monitoring and coronary CTA scan was < 3 months. Every patient completed the Epworth sleepiness scale (ESS) to assess daytime sleepiness, and an ESS score of ≥ 11 was recognized as excessive daytime sleepiness (EDS). Coronary plaque volume and composition were measured using semi-automatic software. RESULTS: Of the 394 patients with OSA (median [IQR] age, 56.0 [49.0-64.0] years; median [IQR] body mass index, 27.9 [25.5-30.2] kg/m2; median [IQR] apnea-hypopnea index, 21.3 [11.7, 36.3] events/h), a total of 200 patients had EDS. In the overall participants, a significant dose-response relationship between ESS scores and low-attenuation plaque volume was found in the fully adjusted model (P = 0.019). Further analysis demonstrated that there was a significant interactive effect of ESS levels and obesity on coronary plaque volume (all P values for interaction analysis < 0.05). Specifically, ESS levels were associated with total plaque volume, volumes of noncalcified, low-attenuation, and calcified plaque (P = 0.008, 0.006, 0.005, and 0.043 respectively) in obese patients with OSA. CONCLUSION: Daytime sleepiness is significantly correlated with increased coronary plaque burden among patients with OSA. Thus, clinicians should recognize that patients with OSA reporting high ESS scores, especially those with obesity, are more prone to experience adverse coronary events.

Comparison of the value of the STOP-BANG questionnaire with oxygen desaturation index in screening obstructive sleep apnea in Germany.

PURPOSE: Despite polysomnography being the gold standard method of diagnosing obstructive sleep apnea (OSA), it is time-consuming and has long waiting lists. Alternative methods including questionnaires and portable sleep devices have been developed to increase the speed of diagnosis. However, most questionnaires such as the STOP-BANG questionnaire (SBQ) are limited due to low specificity. This study evaluated the value of SBQ to screen for OSA and compared it with the oxygen desaturation index (ODI) and their combination. METHODS: This retrospective study included patients who completed the SBQ and underwent a night at the sleep lab or home sleep testing. The ODI was extracted from these sleep study reports. The combination of SBQ with ODI and their individual scores were compared with apnea-hypopnea index (AHI) in terms of their accuracy in diagnosing OSA. Sensitivity, specificity, and area under the curve (AUC) for different severities of OSA were calculated and compared. RESULTS: Among 132 patients, SBQ showed a sensitivity of 0.9 and a specificity of 0.3 to screen for OSA. As the severity of OSA increased, the sensitivity increased whilst specificity decreased for both measurements. ODI achieved an increased specificity of 0.8 and could correctly diagnose OSA 86% of the time which was better than SBQ's 60%. For all severities of OSA, ODI alone displayed a larger AUC than SBQ and similar AUC to their combination. CONCLUSION: ODI produced a higher specificity and AUC than SBQ. Furthermore, ODI combined with SBQ failed to increase diagnostic value. Therefore, ODI may be the preferred way to initially screen patients for OSA as an easy-to-use alternative compared to SBQ.

Persistent Treatment-Emergent Central Sleep Apnea (TECSA) Following Hypoglossal Nerve Stimulation.

Purpose: Since 2001, hypoglossal nerve stimulators (HNS) have been used worldwide to treat patients with obstructive sleep apnea (OSA). Recently, a few studies reported treatment-emergent central sleep apnea (TECSA) with spontaneous resolution following HNS. However, the evidence of persistent development of TECSA during long-term care visits was lacking. As a result, this study first report two patients with persistent TECSA and describe their development phenotype during more than two years of follow-up visits to help explore the influencing factors and underlying mechanisms. Patients and Methods: This retrospective study included twenty-seven patients who underwent HNS implantation from 2016 to 2021. Their demographic data, pre- and postoperative sleep study characteristics, and device use settings were collected. The possible factors associated with post-operative elevated CSA (central apnea index ≥5) were evaluated. Moreover, the development phenotype of the TECSA was observed and followed up with a titration trial study. Results: Among overall 27 patients with OSA, 3 patients with an increased preoperative Epworth Sleepiness Score (ESS) got an elevated CSA (CAI ≥ 5). Two of these 3 patients developed a persistent TECSA with a significant negative correlation between obstructive apnea index (OAI) and central and mixed sleep apnea index (CMAI) (R = -0.745, P = 0.021). These development phenotypes might be associated with different stimulation amplitudes of the HNS device. Furthermore, the following titration trial study also suggested that different amplitudes would influence the development of TECSA following HNS. Conclusion: OSA patients with severe daytime sleepiness are more likely to have elevated CSA following HNS. An inappropriate stimulation amplitude might influence the development course of TECSA in such patients.

The Interplay Between Poor Sleep and Work-Related Health.

Objectives: Sleep disorders can arise from work. Employees who experience work overload are more likely to develop sleep problems. Poor sleep leads to decreased performance, sick leave, and accidents. Therefore, sleep disorders may be linked to workplace hazards as well as decreased occupational health, however, the relationship remains unknown. Methods: This relationship was examined using secondary data analysis of aggregated survey data from 97 companies based in Germany between 2003 and 2020 as part of Workplace Health Management project. Two extreme groups with respect to sleep problems were analyzed (N = 4,865 + 9,795). The survey "Diagnosis of corporate health" contained 137 individual questions which recorded all relevant working conditions, aspects of health, and one question relating to insomnia traits. A one-way analysis of variance was used to examine whether and to what extent the potentials, hazards, and health aspects differed between employees depending on their perceived sleep problems. In addition, multiple linear regressions were used to determine whether and to what extent work characteristics affect various health aspects for both good and poor sleepers. Results: In total, 49.7% of staff reported moderate difficulty falling and/or remaining asleep. These poor sleepers perceived all health potentials worse than good sleepers, especially on scales such as fair assessment, work climate, and learning at work. Furthermore, poor sleepers perceived health hazards (physical environmental stress, job insecurity, and time pressure) more whilst positive health indicators (joy of work and confidence) were perceived less. Conclusion: Overall, the determination of sleep difficulties could be used as a substantial health indicator. Also, these sleep problems are reported more frequently in certain occupations compared to others, which could mean that the perception of sleep health varies between professions. Therefore, it is important to implement specific recommendations for each industry in order to improve working conditions for poor sleepers which in turn, improves their health.

Efficacy on sleep parameters and tolerability of melatonin in individuals with sleep or mental disorders: A systematic review and meta-analysis.

We conducted the first systematic review and series of meta-analyses to assess the efficacy and tolerability of melatonin in children/adolescents or adults with sleep or mental health disorders, using the same set of criteria across disorders and ages. Based on a pre-registered protocol (PROPSPERO: CRD42021289827), we searched a broad range of electronic databases up to 02.02.2021 for randomized control trials (RCTs) of melatonin. We assessed study quality using the Risk of Bias tool, v2. We included a total of 34 RCTs (21 in children/adolescents: N = 984; 13 in adults: N = 1014). We found evidence that melatonin significantly improved sleep onset latency and total sleep time, but not sleep awaking, in children and adolescents with a variety of neurodevelopmental disorders, and sleep onset latency (measured by diary) as well as total sleep time (measured with polysomnography) in adults with delayed sleep phase disorder. No evidence of significant differences between melatonin and placebo was found in terms of tolerability. We discuss clinical and research implications of our findings.