Obstructive sleep apnea severity, circulating biomarkers, and cancer risk

STUDY OBJECTIVES

To determine if obstructive sleep apnea (OSA) severity and/or biomarkers of inflammation/angiogenesis are associated with incident cancer in this clinical cohort.

METHODS

Consenting adult patients at the University of British Columbia Hospital between 2003-2014 completed a questionnaire about their medical history and sleep habits prior to undergoing a polysomnogram (PSG). Blood samples were collected the morning after PSG and processed for biomarkers of inflammation and angiogenesis. The clinical, PSG, and biomarker data were linked to the British Columbia Cancer Registry to ascertain incident cancer diagnoses. Cox proportional hazard regression were used to assess the association between OSA severity and biomarker concentrations with cancer risk.

RESULTS

A total of 1,990 patients were included in the analysis with a mean follow-up time of 12.8 years; 181 of them (9.1%) developed cancer after PSG. OSA severity was significantly associated with cancer risk after controlling for relevant covariates (hazard ratio (HR) = 1.08 per 10 events/h apnea-hypopnea index (AHI) increase, CI = 1.02-1.15, p=0.015). In an exploratory analysis, two biomarkers were significantly associated with an increased cancer risk after controlling for relevant covariates (HR per interquartile range (IQR) pg/mL increase of endostatin = 1.45, CI = 1.12-1.87, p=0.01 and HR for IQR pg/mL increase of VCAM-1 = 1.48, CI = 1.04-2.11, p=0.03, respectively).

CONCLUSIONS

OSA severity was an independent risk factor for cancer. Furthermore, two circulating markers were significantly associated with cancer risk. If these preliminary findings can be reproduced in other cohorts, biomarkers could potentially be used to prognosticate OSA patients with respect to cancer risk.

Correlation between obstructive sleep apnea and hypoperfusion in patients with acute cerebral infarction

Purpose

To explore the relationship between obstructive sleep apnea (OSA) and hypoperfusion during ultra-early acute cerebral infarction.

Patients and methods

Data were retrospectively collected from patients admitted to our hospital with acute cerebral infarction between January 2020 and January 2022, who underwent comprehensive whole-brain computed tomography perfusion imaging and angiography examinations within 6 h of onset. The F-stroke software automatically assessed and obtained relevant data (Tmax). The patients underwent an initial screening for sleep apnea. Based on their Apnea-Hypopnea Index (AHI), patients were categorized into an AHI ≤15 (n = 22) or AHI >15 (n = 25) group. The pairwise difference of the time-to-maximum of the residue function (Tmax) > 6 s volume was compared, and the correlation between AHI, mean pulse oxygen saturation (SpO2), oxygen desaturation index (ODI), percentage of time with oxygen saturation < 90% (T90%), and the Tmax >6 s volume was analyzed.

Results

The Tmax >6 s volume in the AHI > 15 group was significantly larger than that in the AHI ≤ 15 group [109 (62-157) vs. 59 (21-106) mL, p = 0.013]. Spearman's correlation analysis revealed Tmax >6 s volume was significantly correlated with AHI, mean SpO2, ODI, and T90% in the AHI > 15 group, however, no significant correlations were observed in the AHI ≤ 15 group. Controlling for the site of occlusion and Multiphase CT angiography (mCTA) score, AHI (β = 0.919, p < 0.001), mean SpO2 (β = -0.460, p = 0.031), ODI (β = 0.467, p = 0.032), and T90% (β =0.478, p = 0.026) remained associated with early hypoperfusion in the AHI > 15 group.

Conclusion

In patients with acute cerebral infarction and AHI > 15, AHI, mean SpO2, ODI and T90% were associated with early hypoperfusion. However, no such relationship exists among patients with AHI ≤ 15.

The effect of longitudinal sleep monitoring on clinician agreement in obstructive sleep apnea diagnosis: The ELSA study

There is strong evidence for clinically relevant night-to-night variability of respiratory events in patients with suspected obstructive sleep apnea. Sleep experts retrospectively evaluated diagnostic data in 56 patients with suspected obstructive sleep apnea. Experts were blinded to the fact that they were diagnosing the same case twice, once based on a short report of a single in-laboratory respiratory polygraphy and once with the additional information of 14 nights of pulse oximetry at home. All experts (n = 22) were highly qualified, 13 experts (59.1%) treated > 100 patients with suspected obstructive sleep apnea per year. In 12 patients, the apnea-hypopnea index in the respiratory polygraphy was < 5 per hr, but the mean oxygen desaturation index of 14 nights of pulse oximetry was ≥ 5 per hr. The additional information of 14 nights of pulse oximetry helped to diagnose obstructive sleep apnea with a 70% consensus in two of those patients (16.7% [95% confidence interval: 4.7/44.8]). In eight patients, experts could not agree to a 70% consensus regarding continuous positive airway pressure therapy recommendation after respiratory polygraphy. The additional information of multiple-night testing led to a consensus in three of those cases (37.5% [95% confidence interval: 14/69]). Change of obstructive sleep apnea diagnosis and continuous positive airway pressure recommendation was significantly negatively associated with the number of treated obstructive sleep apnea patients > 100 per year compared with 0-29 patients per year (Coef. [95% confidence interval] -0.63 [-1.22/-0.04] and -0.61 [-1.07/-0.15], respectively). Experts found already a high level of consensus regarding obstructive sleep apnea diagnosis, severity and continuous positive airway pressure recommendation after a single respiratory polygraphy. However, longitudinal sleep monitoring could help increase consensus in selected patients with diagnostic uncertainty.

Effect of different anti-cardiovascular disease treatments on the severity of obstructive sleep apnea

Obstructive sleep apnea (OSA) and cardiovascular co-morbidities have a mutually reinforcing effect, but existing studies have focussed only on the improvement of the associated co-morbidities by treatment for OSA. To provide fresh guidelines for the treatment of OSA from a co-morbidity standpoint, we conducted a systematic search of Web of Science, PubMed, EMBASE, and the Cochrane Library for articles published from inception up to 2 May 2023. Fourteen original studies of patients with OSA with cardiovascular co-morbidities and who received related treatment were included in the analysis. We found that diuretic treatment can reduce the apnea-hypopnea index in patients with OSA and hypertension (-19.41/h, p = 1.0 × 10-5 ), aldosterone-angiotensin inhibitors also have a 9.19/h reduction (p = 0.003), while the effect of renal sympathetic denervation is insignificant (-2.32/h, p = 0.19). The short-term treatment (<4 weeks) did not show an improvement (-2.72/h, p = 0.16), while long-term treatment (>4 weeks) produced surprising outcomes (-12.78/h, p = 0.002). Patients with milder disease (baseline AHI < 35/h) had insignificant improvements (-1.05/h, p = 0.46), whereas those with more severe disease (baseline AHI > 35/h) could achieve satisfactory outcomes (-14.74/h, p < 0.00001). In addition, it also showed some improvement in the oxygen desaturation index and blood oxygen. Our results support the additional benefit of antihypertensive treatment for OSA symptoms, and the efficacy can be affected by different therapy, treatment duration, and severity levels. It could be useful in developing clinical therapy, educating patients, and exploring interaction mechanisms. The proposal was registered with PROSPERO (CRD42022351206).

Increased Flow Limitation During Sleep Is Associated With Increased Psychomotor Vigilance Task Lapses in Individuals With Suspected OSA

BACKGROUND

Impaired daytime vigilance is an important consequence of OSA, but several studies have reported no association between objective measurements of vigilance and the apnea-hypopnea index (AHI). Notably, the AHI does not quantify the degree of flow limitation, that is, the extent to which ventilation fails to meet intended ventilation (ventilatory drive).

RESEARCH QUESTION

Is flow limitation during sleep associated with daytime vigilance in OSA?

STUDY DESIGN AND METHODS

Nine hundred ninety-eight participants with suspected OSA completed a 10-min psychomotor vigilance task (PVT) before same-night in-laboratory polysomnography. Flow limitation frequency (percent of flow-limited breaths) during sleep was quantified using airflow shapes (eg, fluttering and scooping) from nasal pressure airflow. Multivariable regression assessed the association between flow limitation frequency and the number of lapses (response times > 500 ms, primary outcome), adjusting for age, sex, BMI, total sleep time, depression, and smoking status.

RESULTS

Increased flow limitation frequency was associated with decreased vigilance: a 1-SD (35.3%) increase was associated with 2.1 additional PVT lapses (95% CI, 0.7-3.7; P = .003). This magnitude was similar to that for age, where a 1-SD increase (13.5 years) was associated with 1.9 additional lapses. Results were similar after adjusting for AHI, hypoxemia severity, and arousal severity. The AHI was not associated with PVT lapses (P = .20). In secondary exploratory analysis, flow limitation frequency was associated with mean response speed (P = .012), median response time (P = .029), fastest 10% response time (P = .041), slowest 10% response time (P = .018), and slowest 10% response speed (P = .005).

INTERPRETATION

Increased flow limitation during sleep was associated with decreased daytime vigilance in individuals with suspected OSA, independent of the AHI. Flow limitation may complement standard clinical metrics in identifying individuals whose vigilance impairment most likely is explained by OSA.

Correlation between polysomnographic parameters and volumetric changes generated by maxillomandibular advancement surgery in patients with obstructive sleep apnea: a fluid dynamics study

STUDY OBJECTIVES

Maxillomandibular advancement surgery (MMA) is a therapeutic option for obstructive sleep apnea (OSA). The main objective of this study was to determine the impact of MMA on the physical and airflow characteristics of the upper airway based on data obtained by computational fluid dynamics (CFD) and to correlate these data with polysomnography parameters. Other objectives included the identification of presurgical variables that could help avoid surgeries likely to have a low success rate.

METHODS

This was a retrospective observational study of 18 patients with moderate-severe OSA who underwent MMA. Polysomnography and computed axial tomography imaging were performed before and after the surgery. Three-dimensional models for CFD study were made based on the images obtained.

RESULTS

MMA achieved an average increase in airway volume of 43.75%, with a mean decrease in the maximum airway velocity of 40.3%. We found significant correlations between improved apnea-hypopnea index values and both the increase in airway volume and decrease in maximum airway speed. Patients with a maximum velocity of less than 7.2 m/s before the intervention had a high rate of surgical failure (43%).

CONCLUSIONS

MMA generates a significant increase in the volume of the upper airway, which was associated with improved flow conditions in the CFD simulation. These findings also correlated with improved polysomnography parameters. Thus, CFD simulation on three-dimensional anatomical models of patients with OSA could contribute to the better selection of candidates for MMA.

CITATION

Furundarena-Padrones L, Cabriada-Nuño V, Brunsó-Casellas J, et al. Correlation between polysomnographic parameters and volumetric changes generated by maxillomandibular advancement surgery in patients with obstructive sleep apnea: a fluid dynamics study. J Clin Sleep Med. 2024;20(3):371-379.

Associations between Vitamin D Status and Polysomnographic Parameters in Adults with Obstructive Sleep Apnea

Vitamin D deficiency (VDD) may be associated with obstructive sleep apnea (OSA) presence and is more pronounced with increasing OSA severity; however, the relationship between these two entities remains unclear. This was a cross-sectional study among 262 adults with in-hospital-attended polysomnography-diagnosed OSA and no additional major comorbidities, aiming to explore possible associations between serum 25-hydroxyvitamin D [25(OH)D] levels and polysomnographic parameters. Data on demographics, medical history, anthropometric indices, and lifestyle habits were collected at enrolment. Serum 25(OH)D was evaluated using chemiluminescence, with VDD defined as 25(OH)D < 20 ng/mL. VDD was observed in 63% of the participants. Serum 25(OH)D correlated negatively with apnea-hypopnea index and other polysomnographic indices (all p < 0.05). In logistic regression analysis, adjusting for age, sex, smoking, body mass index, physical activity, dietary vitamin D intake, and season of blood sampling, serum 25(OH)D was associated with lower odds of severe OSA [odds ratio (95% confidence interval): 0.94 (0.90-0.98)]. In the same multivariate model, VDD was associated with ~threefold higher odds of severe OSA [2.75 (1.38-5.48)]. In stratified analyses, VDD predicted OSA severity in the group of participants ≥50 y [3.54 (1.29-9.68)] and among those with body mass index ≥ 30 kg/m2 [3.38 (1.52-7.52)], but not in the younger and non-obese adults. This study provides further evidence of an inverse association between vitamin D levels and OSA severity and underscores the importance of considering vitamin D status as a potential modifiable factor in the comprehensive management of OSA.

Nocturnal oxygen saturation is associated with all-cause mortality: a community-based study

STUDY OBJECTIVES

Observational studies have demonstrated the association between the single-point measurement of oxygen saturation (SpO2) level and mortality in the general population. This study aimed to evaluate whether nocturnal SpO2 level could predict all-cause mortality in a community-based population.

METHODS

The study samples were obtained from the Sleep Heart Health Study, which included 2,280 men and 2,606 women (mean age, 63.8 ± 11.1 years). A pulse oximeter based on overnight in-home polysomnography was used to monitor SpO2 levels during total sleep time (SpO2-TOTAL). Multivariable Cox proportional hazards analysis was performed to examine the association between nocturnal SpO2 and all-cause mortality.

RESULTS

During the follow-up period of 10.7 ± 3.0 years, 1,110 (22.7%) people died. After adjusting for confounding factors, multivariable Cox regression analysis showed that the average SpO2-TOTAL (hazard ratio [HR] 0.93; 95% confidence interval [CI] 0.90-0.96, P < .001) was associated with all-cause mortality. These findings remained stable in individuals with low and high apnea-hypopnea index levels. Additionally, maximum SpO2-TOTAL (HR, 0.91; 95% CI, 0.87-0.96; P = .001) and minimum SpO2-TOTAL (HR, 0.98; 95% CI, 0.97-0.99; P = .001) could predict all-cause mortality. A significant association between nocturnal hypoxemia and all-cause mortality was also observed.

CONCLUSIONS

Our findings highlight the importance of monitoring nocturnal SpO2 level and improving hypoxemia in the general populations.

CITATION

Yan B, Gao Y, Zhang Z, Shi T, Chen Q. Nocturnal oxygen saturation is associated with all-cause mortality: a community-based study. J Clin Sleep Med. 2024;20(2):229-235.

The relationship between obstructive sleep apnea and visual hallucinations in PD patients: a polysomnography study

Purpose

Parkinson's disease (PD) patients frequently experience visual hallucinations (VHs) and obstructive sleep apnea (OSA). The aim of this study was to describe the prevalence and clinical correlates of VHs and OSA in the Chinese population with PD.

Materials and methods

A sample of 489 PD patients was recruited for the present study. Patients were categorized as having formed VHs (FVHs) or minor VHs (MVHs) or as non-hallucinators (NVHs) according to the Unified Parkinson's Disease Rating Scale (UPDRS) and an initial questionnaire. Polysomnography (PSG) was used for objective assessment of sleep.

Results

VHs were observed in 143 (29.2%) patients. Among them, 75 of the hallucinators experienced MVHs, and 68 experienced FVHs. The disease duration, UPDRS Part III score, Hoehn and Yahr (H-Y) stage, Pittsburgh Sleep Quality Index (PSQI) score and rapid eye movement (REM) sleep behavior disorder (RBD) score of hallucinators were significantly greater than those of non-hallucinators (P < 0.05). We also observed OSA in 38.7, 54.7, and 63.3% of the NVH, MVH, and FVH groups, respectively. PSG showed that the VH groups had a lower total sleep time, lower sleep efficiency, higher arousal index, lower sleep latency, lower N1%, higher apnea-hypopnea index (AHI), higher average duration of apnea, higher respiratory-related arousal (RRA), and lower values of the lowest O2 and mean O2. The forward binary logistic regression model showed that AHI, N1%, RRA and lowest O2 were independently associated with VHs in PD patients.

Conclusions

Our results confirm the high prevalence of VHs and OSA as well as their relationship in patients with PD.

Unstable periodontal disease and its association with sleep-disordered breathing

Periodontal therapy results in successful disease management for some patients, but patients whose periodontal disease cannot be managed with standard-of-care protocols are treated repeatedly without success. For this set of patients, a systemic rather than an oral origin is possible. This clinical study investigated the connection between unresolved periodontal disease and sleep-disordered breathing (SDB) in 71 patients (44 women and 27 men), aged 19 to 75 years (mean, 45 years), who were enrolled in periodontal maintenance therapy for Stage I or II periodontitis. The results of an at-home sleep testing device served as the basis for evaluating 4 SDB screening tools: Papillary Bleeding Index (PBI), Epworth Sleepiness Scale (ESS) questionnaire, STOP-Bang questionnaire, and salivary cortisol testing. At-home sleep testing indicated that 33 participants had an apnea-hypopnea index ≥ 5, signifying probable obstructive sleep apnea. A finding of unstable periodontal disease (PBI ≥ 2) was able to identify 21 of these 33 participants, while the ESS and STOP-Bang questionnaires identified only 2 and 6 participants, respectively. The difference between the PBI and both the ESS and STOP-Bang questionnaires was statistically significant (P < 0.05; 2-sample proportion test). There was no relationship between participants' cortisol levels and the PBI findings. This clinical study found a link between unresolved periodontal disease and SDB. The results of this study suggested that the PBI is a reliable, objective means for general dentists to identify SDB in patients with unresolved periodontal disease. Once identified, these patients can be referred for treatment to address their SDB, which may positively impact management of their periodontal disease.

Performance of the Alice PDx Device With the Somnolyzer Automated Scoring Algorithm for the Diagnosis of Obstructive Sleep Apnea

Objective Automated scoring of respiratory events could allow a swifter obstructive sleep apnea (OSA) identification. We assessed the accuracy of the Alice PDx device with the Somnolyzer automated scoring algorithm, compared to the manually reviewed scoring by a trained sleep technician, for the diagnosis of OSA. Methods A prospective study was conducted between March 2021 and March 2022 in Centro Hospitalar do Baixo Vouga, a level 2 hospital in Aveiro, Portugal. Patients with high pre-test probability for OSA performed a type III home sleep apnea testing with the Alice PDx device. Data were scored automatedly by the Sleepware G3 with the Somnolyzer digital system and manually by a trained sleep technician. Correlation and dependent t-tests were used. Sensitivity, specificity, positive predictive values (PPVs), negative predictive values (NPVs), and area under the receiver operating characteristic curve (AUROC) of automated scoring were calculated. Data were analyzed using the Stata Statistical Software (Release 17, StataCorp., 2023, College Station, TX: StataCorp LLC). Results In 150 participants (mean age 57.8 ± 13.9 years), the mean apnea-hypopnea index (AHI) was 21.9 ± 21.8 events/hour by manual scoring and 25.4 ± 21.6 events/hour by automated scoring. The mean difference was 3.4 ± 4.4 events/hour, and a strong, positive, linear correlation was found between the two scores (r = 0.98). At the altered AHI (AHI ≥ 5 events/hour), mild, moderate, and severe OSA, the automated scoring sensitivity/specificity values were 91.2%/100.0%, 80.0%/68.6%, 91.6%/41.9%, and 98.1%/80.9%, respectively. The PPVs/NPVs for the same categories were 100.0%/69.4%, 89.3%/51.1%, 79.7%/66.7%, and 91.8%/95.0%, respectively. Finally, the AUROC was 0.85, 0.70, 0.73, and 0.93, respectively. Conclusion The automated scoring obtained from the Alice PDx portable device, using Sleepware G3 with the Somnolyzer digital system, seems accurate enough to diagnose OSA and validate the initiation of PAP therapy in the correct clinical setting. Nevertheless, it does not replace manual reviewing by a trained sleep technician in the case of mild and moderate OSA, to obtain a correct severity classification. With this valuable time-saving tool, we expect to hasten OSA diagnosis and treatment and thus tackle the underdiagnosis problem.

Orofacial Myofunctional Therapy for Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis

OBJECTIVE

Orofacial myofunctional therapy (OMT) is an alternative form of treatment of obstructive sleep apnea (OSA), that incorporates various exercises to optimize tongue placement and increase oropharyngeal tone. The objective of this systematic review and meta-analysis is to determine the efficacy of OMT in OSA patients.

DATA SOURCES

PubMed/Medline, EMBASE, Cochrane, Web of Science.

REVIEW METHODS

Using PRISMA guidelines, a directed search strategy was performed for randomized control trials (RCTs) published prior to March 24, 2023, featuring 10+ patients with OSA undergoing mono-therapeutic OMT. The primary outcome of interest was apnea-hypopnea index (AHI). Secondary outcomes included subjective sleepiness, sleep-related quality-of-life, and snoring frequency.

RESULTS

Of the 1244 abstracts that were identified, 7 RCTs involving 310 patients met inclusion criteria. Adult OMT patients had a statistically significant improvement in AHI (MD -10.2; 95% CI, -15.6, -4.8, p < 0.05), subjective sleepiness (Epworth Sleepiness Scale; MD -5.66; 95% CI, -6.82, -4.5, p < 0.05), sleep-related quality-of-life (Pittsburgh Sleep Quality Index; MD -3.00; 95% CI, -4.52, -1.49, p < 0.05), and minimum oxygen saturation (MD 2.71; 95% CI, 0.23, 5.18, p < 0.05) when compared with sham OMT or no therapy. Within the single RCT featuring pediatric OMT patients, patients had poor compliance (<50%) and did not show any improvements in AHI, minimum oxygen saturation, or snoring frequency.

CONCLUSION

OMT may provide a reasonable alternative for OSA patients who cannot tolerate CPAP or other more established treatment options. OMT benefits appear limited in children due to poor compliance. More studies are required to evaluate compliance and the long-term effects of OMT on OSA outcomes.

LEVEL OF EVIDENCE

1 Laryngoscope, 134:480-495, 2024.

Prevalence of Obstructive Sleep Apnea Using Home Sleep Test in Taiwan During the Coronavirus Disease Pandemic

Background

Obstructive sleep apnea syndrome (OSAS) is a common disorder associated with serious sequelae. The current gold standard diagnostic method, polysomnography, is costly and time consuming and requires patients to stay overnight at a facility.

Aim

This study aimed to reveal the prevalence of OSAS in general adult population using a home sleep test (HST) during the coronavirus disease 2019 (COVID-19) pandemic.

Methods

This prospective cohort study was conducted by the Department of Otolaryngology, Taipei City Hospital, Taipei, Taiwan, between January 2020 and December 2021. A total of 1372 patients aged 30-70 years completed an HST using a Type 3 portable sleep monitor (PM). The apnea-hypopnea index (AHI) was analyzed to assess the association of OSAS with age, body mass index (BMI), sex, Epworth Sleepiness Scale (ESS) and the Sleep Apnea Risk Assessment questionnaire (STOP-Bang questionnaire) rating.

Results

The mean age of the patients (782 men, 57%; 590 women, 43%) was 49.24 ± 11.04 years. OSAS was detected in 954 (69.5%) patients with 399 (29.1%) mild OSAS; 246 (17.9%) moderate OSAS; and 309 (22.5%) severe OSAS. Among these, the prevalence of moderate-to-severe OSAS was 143 (10.4%) in women and 412 (30.0%) in men. The mean age was the highest (51.29 ± 11.29) in the mild OSAS group and lowest (47.08 ± 10.87) in the healthy group. OSAS severity was greater with increasing BMI, 23.39 ± 3.44 in the healthy group and 29.29 ± 5.01 in the severe OSAS group. A positive correlation was also noted between the ESS/STOP-Bang questionnaire rating and OSAS severity.

Conclusion

The prevalence of OSAS in Taiwan was 69.5% in our study. It showed strong evidence that OSAS has important public health consequences and PMs are simple, fast, feasible, and cost-effective tools for OSAS screening in the home environment, especially during the COVID-19 pandemic.

Redefining Comorbid Insomnia and Sleep Apnea: The Association of Sleep Breathing Impairment and Insomnia with Incident Diabetes

Rationale: Obstructive sleep apnea (OSA) is a prevalent sleep disorder that is frequently comorbid with insomnia and often accompanied by metabolic diseases such as type 2 diabetes. Although the apnea-hypopnea index (AHI) is currently the diagnostic criterion for gauging the severity of OSA, the AHI has not consistently predicted incident diabetes. Objectives: To test whether a combined insomnia-OSA (COMISA) phenotype based on comorbid insomnia and sleep breathing impairment index (COMISA-SBII) predicts incident diabetes and to compare the association with an AHI definition of COMISA (COMISA-AHI) in the MrOS (Osteoporotic Fractures in Men) study. Methods: The study samples came from participants in the MrOS sleep study without diabetes at their baseline examination. The SBII was derived as the product of the duration of each respiratory event (apnea and hypopnea) and the accompanying desaturation area from baseline unattended polysomnography. A subgroup of individuals classified as having comorbid insomnia (difficulties falling asleep, waking up in the middle of the night and/or early morning awakenings >15 times per month, and daytime impairments) and sleep breathing impairment (greater than 50th percentile of SBII) were identified at baseline. The primary outcome was incident diabetes during the follow-up visits. Cox proportional models were built to assess the adjusted hazard ratios of COMISA-AHI and COMISA-SBII. Prediction model performances of incident diabetes were compared across different models. Results: A total of 2,365 men (mean age, 76 yr) without diabetes at baseline were included. During a median follow-up of 10.0 years, diabetes developed in 181. After adjusting for demographic characteristics, comorbidities, and behavioral risk factors, participants with COMISA-SBII had a higher risk of incident diabetes (hazard ratio, 1.82; 95% confidence interval, 1.15-2.89) than those without sleep disorders (those with an SBII ⩽13.17 and no insomnia). The result remained significant in the risk competing model. Compared with COMISA-AHI, the addition of COMISA-SBII to a crude model with established risk factors significantly improved the predictive value of incident diabetes. Conclusions: COMISA-SBII, but not COMISA-AHI, predicted incident diabetes after accounting for multiple covariates in a cohort of older men. A comorbid insomnia phenotype based on SBII plus insomnia symptoms may be an important clinical subtype.

Long-Term Generator Replacement Experience in Hypoglossal Nerve Stimulator Therapy Recipients With CPAP-Intolerant Obstructive Sleep Apnea

OBJECTIVE

In the last decade, hypoglossal nerve stimulation (HNS) has emerged as a therapeutic alternative for patients with obstructive sleep apnea. The original clinical trial cohorts are entering the phase of expected battery depletion (8-12 years). This study aimed to examine the surgical experience with implantable pulse generator (IPG) replacements and the associated long-term therapy outcomes.

STUDY DESIGN

Retrospective analysis of patients from the original clinical trial databases (STAR, German post-market) who were followed in the ongoing ADHERE registry.

SETTING

International multicenter HNS registry.

METHODS

The ADHERE registry and clinical trial databases were cross-referenced to identify the serial numbers of IPGs that were replaced. Data collection included demographics, apnea-hypopnea index (AHI), therapy use, operative times, and adverse events.

RESULTS

Fourteen patients underwent IPG replacement 8.3 ± 1.1 years after their initial implantation. Body mass index was unchanged between the original implant and IPG replacement (29 ± 4 vs 28 ± 2 kg/m2 , p = .50). The mean IPG replacement operative time was shorter than the original implant (63 ± 50 vs 154 ± 58 minutes, p < .002); however, 2 patients required stimulation lead replacement which significantly increased operative time. For patients with available AHI and adherence data, the mean change in AHI from baseline to latest follow-up (8.7 ± 1.1 years after de novo implant) was -50.06%, and the mean therapy use was 7.2 hours/night.

CONCLUSION

IPG replacement surgery was associated with low complications and shorter operative time. For patients with available outcomes data, adherence and efficacy remained stable after 9 years of follow-up.

Obstructive Sleep Apnea and a Comprehensive Remotely Supervised Rehabilitation Program: Protocol for a Randomized Controlled Trial

BACKGROUND

Obstructive sleep apnea (OSA) is characterized by recurrent, intermittent partial or complete obstruction of the upper respiratory tract during sleep, which negatively affects the patient's daily quality of life (QoL). Middle-aged and older men who smoke and have obesity are most at risk. Even though the use of continuous positive airway pressure (CPAP) during sleep remains the gold standard treatment, various rehabilitation methods, such as exercise, respiratory therapy, myofunctional therapy, and nutritional lifestyle interventions, also appear to be effective. Moreover, it is increasingly recommended to use alternative or additional therapy options in combination with CPAP therapy.

OBJECTIVE

This study aims to evaluate if a comprehensive home-based, remotely supervised rehabilitation program (tele-RHB), in combination with standard therapy, can improve OSA severity by decreasing the apnea-hypopnea index (AHI); improve objective parameters of polysomnographic, spirometric, anthropometric, and body composition examinations; improve lipid profile, maximal mouth pressure, and functional capacity tests; and enhance the subjective perception of QoL, as well as daytime sleepiness in male participants with moderate to severe OSA. Our hypothesis is that a combination of the tele-RHB program and CPAP therapy will be more effective by improving OSA severity and the abovementioned parameters.

METHODS

This randomized controlled trial aims to recruit 50 male participants between the ages of 30 and 60 years with newly diagnosed moderate to severe OSA. Participants will be randomized 1:1, either to a 12-week tele-RHB program along with CPAP therapy or to CPAP therapy alone. After the completion of the intervention, the participants will be invited to complete a 1-year follow-up. The primary outcomes will be the polysomnographic value of AHI, Epworth Sleepiness Scale score, 36-Item Short Form Health Survey (SF-36) score, percentage of body fat, 6-minute walk test distance covered, as well as maximal inspiratory and expiratory mouth pressure values. Secondary outcomes will include polysomnographic values of oxygen desaturation index, supine AHI, total sleep time, average heart rate, mean oxygen saturation, and the percentage of time with oxygen saturation below 90%; anthropometric measurements of neck, waist, and hip circumference; BMI values; forced vital capacity; forced expiratory volume in 1 second; World Health Organization's tool to measure QoL (WHOQOL-BREF) score; and lipid profile values.

RESULTS

Study recruitment began on October 25, 2021, and the estimated study completion date is December 2024. Analyses will be performed to examine whether the combination of the tele-RHB program and CPAP therapy will be more effective in the reduction of OSA severity and improvement of QoL, body composition and circumferences, exercise tolerance, lipid profile, as well as respiratory muscle and lung function, compared to CPAP therapy alone.

CONCLUSIONS

The study will evaluate the effect of a comprehensive tele-RHB program on selected parameters mentioned above in male participants. The results of this intervention could help the further development of novel additional therapeutic home-based options for OSA.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04759456; https://clinicaltrials.gov/ct2/show/NCT04759456.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/47460.

Autonomic arousal detection and cardio-respiratory sleep staging improve the accuracy of home sleep apnea tests

Introduction: The apnea-hypopnea index (AHI), defined as the number of apneas and hypopneas per hour of sleep, is still used as an important index to assess sleep disordered breathing (SDB) severity, where hypopneas are confirmed by the presence of an oxygen desaturation or an arousal. Ambulatory polygraphy without neurological signals, often referred to as home sleep apnea testing (HSAT), can potentially underestimate the severity of sleep disordered breathing (SDB) as sleep and arousals are not assessed. We aim to improve the diagnostic accuracy of HSATs by extracting surrogate sleep and arousal information derived from autonomic nervous system activity with artificial intelligence. Methods: We used polysomnographic (PSG) recordings from 245 subjects (148 with simultaneously recorded HSATs) to develop and validate a new algorithm to detect autonomic arousals using artificial intelligence. A clinically validated auto-scoring algorithm (Somnolyzer) scored respiratory events, cortical arousals, and sleep stages in PSGs, and provided respiratory events and sleep stages from cardio-respiratory signals in HSATs. In a four-fold cross validation of the newly developed algorithm, we evaluated the accuracy of the estimated arousal index and HSAT-derived surrogates for the AHI. Results: The agreement between the autonomic and cortical arousal index was moderate to good with an intraclass correlation coefficient of 0.73. When using thresholds of 5, 15, and 30 to categorize SDB into none, mild, moderate, and severe, the addition of sleep and arousal information significantly improved the classification accuracy from 70.2% (Cohen's κ = 0.58) to 80.4% (κ = 0.72), with a significant reduction of patients where the severity category was underestimated from 18.8% to 7.3%. Discussion: Extracting sleep and arousal information from autonomic nervous system activity can improve the diagnostic accuracy of HSATs by significantly reducing the probability of underestimating SDB severity without compromising specificity.

Upper Airway Stimulation in Female Patients: Safety and Efficacy of a Novel Lateral Approach

OBJECTIVE

To describe a novel lateral approach for hypoglossal nerve stimulator (HNS) implantation in women and provide evidence for its safety and efficacy.

STUDY DESIGN

Retrospective case series.

SETTING

Single academic medical center.

METHODS

We identified patients implanted with HNS by a single surgeon from January 2017 to December 2021. Patient characteristics, postoperative complications, surgical duration, response to therapy, and need for revision surgery were recorded.

RESULTS

One hundred four patients were included, including 93 males and 11 females. The lateral approach for HNS implantation involves placing the chest incision for the implantable pulse generator and respiratory sensor lead vertically in the anterior axillary line instead of horizontally in the infraclavicular area. No changes are made to the stimulator lead placement. All female patients were implanted using a lateral approach and all male patients were implanted via the standard anterior approach. Half of the patients were implanted via a 2-incision technique. The median surgical time duration was equivalent in male and female patients (119 [interquartile range (IQR): 105-138] vs 126 [IQR: 115-141], respectively). Revision was required in 2 (18%) females versus 6 (6%) males (p = .17). There were equivalent rates of therapy response as well as postoperative complications.

CONCLUSION

A more cosmetic lateral approach is feasible for HNS in female patients and has a similar rate of adverse events and therapy responsiveness. Additional considerations in female patients include the ability to tolerate mammography as well as HNS implantation in the setting of existing breast implants.

Good clinical response achieved by changing servo-ventilation devices in a patient with central sleep apnea: a case report

Servo-ventilation (SV) was developed for treating central sleep apnea. To date, primarily SV devices manufactured by Philips Respironics and ResMed are used. However, the difference in reaction to sleep-disordered breathing events between bilevel positive airway pressure AutoSV devices from Philips and adaptive SV devices from ResMed in clinical settings is unknown. Herein, we describe a case of central sleep apnea in which sleep-disordered breathing events were successfully controlled and sleepiness, sleep quality, and tolerance of the device were improved by changing from the bilevel positive airway pressure AutoSV device from Philips to the adaptive SV device from ResMed. Changing the SV devices can be a clinical option to appropriately control sleep-disordered breathing events in patients receiving SV therapy who present with persistent sleep-disordered breathing.

CITATION

Hamada S, Togawa J, Sunadome H, Nagasaki T, Hirai T, Sato S. Good clinical response achieved by changing servo-ventilation devices in a patient with central sleep apnea: a case report. J Clin Sleep Med. 2023;19(8):1557-1561.

Association between obstructive sleep apnea and gastroesophageal reflux disease: A systematic review and meta-analysis

BACKGROUND AND AIM

We aim to conduct a systematic review and determine the association between obstructive sleep apnea (OSA) and gastroesophageal reflux disease (GERD).

METHODS

Literature search for eligible studies was performed across major databases. The main endpoint was to assess the association between GERD and OSA. Subgroup analyses were performed to determine this strength of the association stratified by the diagnostic tools used for OSA (nocturnal polysomnogram or Berlin questionnaire) and GERD (validated reflux questionnaire or esophagogastroduodenoscopy). We also compared sleep efficiency, apnea hypopnea index, oxygen desaturation index, and Epworth Sleepiness Scale in OSA patients with or without GERD. Results were pooled together using Reviewer Manager 5.4.

RESULTS

Six studies involving 2950 patients with either GERD or OSA were included in the pooled analysis. Our findings suggest that there was a statistically significant unidirectional association between GERD and OSA (odds ratio [OR] = 1.53, P = 0.0001). Subgroup analyses redemonstrated an OSA-GERD association irrespective of the tools used for diagnosing either GERD or OSA (P = 0.24 and P = 0.82, respectively). Sensitivity analyses demonstrated the same association after controlling for gender (OR = 1.63), BMI (OR = 1.81), smoking (OR = 1.45), and alcohol consumption (OR = 1.79). In patients with OSA, there were no statistically significant differences between patients with or without GERD in terms of apnea hypopnea index (P = 0.30), sleep efficiency (P = 0.67), oxygen desaturation index (P = 0.39), and Epworth Sleepiness Scale (P = 0.07).

CONCLUSION

There exists an association between OSA and GERD that is independent of the modalities used for screening or diagnosing both disorders. However, the presence of GERD did not affect the severity of OSA.

Obesity, Bariatric Surgery and Obstructive Sleep Apnea-A Narrative Literature Review

The purpose of this review was to analyze the available literature on the subject of obesity and obstructive sleep apnea. We searched for available articles for the time period from 2013 to 2023. Obesity is listed as one of the most important health issues. Complications of obesity, with obstructive sleep apnea (OSA) listed among them, are common problems in clinical practice. Obesity is a well-recognized risk factor for OSA, but OSA itself may contribute to worsening obesity. Bariatric surgery is a treatment of choice for severely obese patients, especially with present complications, and remains the only causative treatment for patients with OSA. Though improvement in OSA control in patients after bariatric surgery is well-established knowledge, the complete resolution of OSA is achieved in less than half of them. The determination of subpopulations of patients in whom bariatric surgery would be especially advantageous is an important issue of OSA management. Increasing the potential of non-invasive strategies in obesity treatment requires studies that assess the efficacy and safety of combined methods.

Description of a novel method for detection of sleep-disordered breathing in brachycephalic dogs

BACKGROUND

Sleep-disordered breathing (SDB), defined as any difficulty in breathing during sleep, occurs in brachycephalic dogs. Diagnostic methods for SDB in dogs require extensive equipment and laboratory assessment.

OBJECTIVES

To evaluate the usability of a portable neckband system for detection of SDB in dogs. We hypothesized that the neckband is a feasible method for evaluation of SDB and that brachycephaly predisposes to SDB.

ANIMALS

Twenty-four prospectively recruited client-owned dogs: 12 brachycephalic dogs and 12 control dogs of mesocephalic or dolicocephalic breeds.

METHODS

Prospective observational cross-sectional study with convenience sampling. Recording was done over 1 night at each dog's home. The primary outcome measure was the obstructive Respiratory Event Index (OREI), which summarized the rate of obstructive SDB events per hour. Additionally, usability, duration of recording, and snore percentage were documented.

RESULTS

Brachycephalic dogs had a significantly higher OREI value (Hodges-Lehmann estimator for median difference = 3.5, 95% confidence interval [CI] 2.2-6.8; P < .001) and snore percentage (Hodges-Lehmann estimator = 34.2, 95% CI 13.6-60.8; P < .001) than controls. A strong positive correlation between OREI and snore percentage was detected in all dogs (rs = .79, P < .001). The neckband system was easy to use.

CONCLUSIONS AND CLINICAL IMPORTANCE

Brachycephaly is associated with SDB. The neckband system is a feasible way of characterizing SDB in dogs.

A panoramic view of a cohort of obstructive sleep apnea patients on positive airway pressure therapy using cloud based telemonitoring devices

Background

Positive airway pressure therapy is mainstay of treatment of obstructive sleep apnea (OSA). But long-term compliance with is poor with such therapy. A proactive and vigilant management may improve the PAP therapy usage. Cloud-based telemonitoring PAP devices offer an opportunity for proactive monitoring and prompt interventions related to PAP troubleshooting. This technology is also used in India for adult OSA patients. But we lack our own data on behavior of Indian patients as a cohort on PAP therapy. The present study is an attempt to look at the behavior a cohort of PAP users in OSA.

Methodology

This study was planned as a retrospective analysis of data of OSA patients who were using a cloud-based PAP devices. First 100 patients were chosen for data retrieval that who was on this therapy. The data was obtained for those patients who were on PAP for at least 7 days and maximum follow-up was available up to 390 days. Descriptive statistical analysis has been carried out in the present study.

Results

The number of male and female patients was 75 and 25, respectively. Overall good compliance was present in 66% of patients. 34% of patients were not compliant with PAP during follow-up. The compliance was statistically same in both the sexes (P = 0.8088). Incomplete data recovery was present in 17 patients and 11 (64.70%) were non-compliant among them. In the initial, 60 days non-compliant patients were more than compliant patients. The difference was lost in 60 to 90 days of use. The air leak was present more in the compliant group than non-compliant group (P = 0.0239). 75.75% of compliant patients had achieved AHI control, whereas 35.29% of non-compliant patients also achieved AHI control. But overall, AHI control was poor in non-compliant patients and 61.76% of non-compliant patients had an AHI uncontrolled.

Conclusions

We conclude that 3/4th of the compliant patients achieve AHI control while 1/4th didn't. This 1/4th population needs further exploration to determine the causes of poor AHI control. Cloud-based PAP devices give an easy opportunity to monitor patients of OSA. It gives an instant panoramic view of behavior of OSA patients on PAP therapy. The compliant patients can be tracked, and non-compliant patients can be segregated quickly.

[Cerebral microangiopathy in men with obstructive sleep apnea syndrome]

OBJECTIVE

To determine factors associated with the development of small vessel disease (SVD) in patients with obstructive sleep apnea syndrome (OSA).

MATERIAL AND METHODS

One hundred and fifty-two patients with risk factors for the development of cerebrovascular diseases were examined. Based on the results of polysomnography, patients were divided into groups with- (n=84) and without (n=68) OSA. The groups were matched by age, prevalence of arterial hypertension and diabetes mellitus. SVD was diagnosed using brain MRI. Laboratory tests included an assessment of parameters of lipid metabolism, glucose metabolism, concentration of C-reactive protein (CRP), levels of homocysteine and creatinine with the calculation of glomerular filtration rate (GFR).

RESULTS

Patients with OSA, compared with those without OSA, were characterized by a statistically significant number of gliosis foci, with their large sizes, more frequent changes on the Fazekas scales and the Hassan scale. The most severe degree of damage according to the Hassan scale in patients with OSA was detected more often (55 (66%) and 27 (39%) OR=2.89, 95% CI 1.47-5.67, p=0.002). More pronounced atrophic changes in the brain, an increase in the size of the III ventricle and the index of the anterior horns, significantly lower GFR and higher levels of CRP were noted in the OSA group. Patients with OSA and duration of nocturnal hypoxia for more than 2 minutes were more likely to have hyperintensity of subcortical regions. In patients with OSAS, pronounced manifestations of SMD were associated with a significantly higher level of morning systolic blood pressure (MAP): 140 [120; 150] vs. 127 [120; 130] p=0.029; increased levels of blood homocysteine: 14 [11; 17.8] vs. 13 [9.7; 12.5] p=0.049; a decrease in GFR: 79 [71; 87.3] vs. 89.8 [80.3; 94] p=0.002, respectively.

CONCLUSION

OSA and intermittent nocturnal hypoxia are independent risk factors for SMD. A more severe micro-focal vascular lesion in OSA is associated with a decrease in renal filtration function, an increase in morning blood pressure and an elevation in homocysteine level.

Adherence to Continuous Positive Airway Pressure Therapy in Pediatric Patients with Obstructive Sleep Apnea: A Meta-Analysis

Introduction

Obstructive sleep apnea (OSA) is a public health problem that affects children. Although continuous positive airway pressure (CPAP) therapy is effective, the CPAP adherence rate in children is varied. This study aimed to evaluate the CPAP adherence rate and factors associated with CPAP adherence in children with OSA using a systematic review.

Methods

The inclusion criteria were observational studies conducted in children with OSA and assessed adherence of CPAP using objective evaluation. The literature search was performed in four databases. Meta-analysis using fixed-effect model was conducted to combine results among included studies.

Results

In all, 34 studies that evaluated adherence rate and predictors of CPAP adherence in children with OSA were included, representing 21,737 patients with an average adherence rate of 46.56%. There were 11 calculations of factors predictive of CPAP adherence: age, sex, ethnicity, body mass index, obesity, income, sleep efficiency, the apnea-hypopnea index (AHI), severity of OSA, residual AHI, and lowest oxygen saturation level. Three different factors were linked to children with adherence and non-adherence to CPAP: age, body mass index, and AHI.

Conclusion

The CPAP adherence rate in children with OSA was 46.56%. Young age, low body mass index, and high AHI were associated with acceptable CPAP adherence in children with OSA.

Quality of life in patients with obstructive sleep apnea: Results from the study of health in Pomerania

Obstructive sleep apnea is known to be an overall public health problem that, among other things, increases morbidity and mortality. Risk factors as well as symptoms of this multidimensional sleep-related breathing disorder negatively affect quality of life. With our study we aimed to expose the association between obstructive sleep apnea and quality of life in the population of Pomerania, Germany. We utilized data from the population-based Study of Health in Pomerania (SHIP). Information on health status and risk factors about 4420 participants (2275 women) were gathered within the cohort SHIP-TREND, of which 1209 (559 women) underwent an overnight polysomnography and completed sleep questionnaires. The quality of life of the participants was measured using the Short-Form 12 questionnaire. For our study, an ordinal regression analysis with age, sex, body mass index and the Short-Form 12 health survey as predictors for apnea-hypopnea index was computed. The potential factors affecting quality of life are different between physical and mental dimensions of quality of life. Significant effects were found regarding age, sex, body mass index and the Short-Form 12 Mental Component Score, but not the Physical Component Score.

In search of a cut-off apnea-hypopnea index in type 3 home portable monitors to diagnose and treat obstructive sleep apnea: a mathematical simulation

The American Academy of Sleep Medicine (AASM) uses similar apnea-hypopnea index (AHI) cut-off values to diagnose and define severity of sleep apnea independent of the technique used: in-hospital polysomnography (PSG) or type 3 portable monitoring (PM). Taking into account that PM theoretically might underestimate the AHI, we explored whether a lower cut-off would be more appropriate. We performed mathematical re-calculations on the diagnostic PSG-AHI (scored using AASM 1999 rules) of 865 consecutive patients with an AHI of ≥20 events/h who started continuous positive airway pressure (CPAP). For a PSG-AHI of ≥15 events/h re-scored using AASM 2012 rules (PSG-AHI^AASM2012 ), a PM-respiratory event index (REI)^AASM2012 cut-off point of ≥15 events/h resulted in a post-test probability of 100% of having the disease, but with negative tests in 57.1%. A PM-REI^AASM2012 cut-off of 8 events/h, still resulted in a positive post-test probability of 100% but with negative tests in only 34.3%. Combination of the cut-off values with clinical estimation of being 'at high risk' based on Epworth Sleepiness Scale (ESS) and Berlin Questionnaire scores only resulted in a small reduction in the percentage of negative tests (respectively 52.7% and 32.7%). After 6 months, CPAP adherence was not lower using the PM-REI^{AASM 2012} cut-off ≥8 events/h in comparison to ≥15 events/h (median 5.7 vs. 5.8 h/night, p = 0.368) and the reduction in ESS was similar too (median -4 and -5 points, p = 0.083). Consequently, using a lower PM-REI^AASM2012 cut-off could result in cost savings because of less negative studies and lesser need for a confirmatory PSG or a performance of a CPAP trial.

The effectiveness of sleep breathing impairment index in assessing obstructive sleep apnea severity

STUDY OBJECTIVES

Using the apnea-hypopnea index (AHI) and the sleep breathing impairment index (SBII) to assess the severity of obstructive sleep apnea (OSA) to study how effective SBII is in assessing the severity and cardiovascular disease (CVD) prognosis.

METHODS

This study comprised a total of 147 patients with diagnosed OSA. The AHI and SBII were calculated from the polysomnography. Patients were enrolled in the cluster analysis using 20 symptoms and the SBII. The prognostic indicator was determined as the moderate-to-high Framingham 10-year CVD risk.

RESULTS

Cluster analysis revealed 3 separate groups: cluster 1 (n = 45, 30.61%) had the lowest symptoms complaints yet the highest PSQI score; cluster 2 (n = 70, 47.62%) had considerably increased symptom complaints but the lowest Epworth Sleepiness Scale score, intermediate PSG indices, a higher low arousal threshold possibility, and a lower SBII quantile; cluster 3 (n = 32, 21.77%) had the largest percentage of smokers, a predominant symptom of restless sleep, severe PSG characteristics, a lower low arousal threshold likelihood, a greater SBII quantile and a higher Framingham CVD risk. There were no differences in severity indicated by AHI between groups. Higher SBII rather than AHI is associated with an increased 10-year CVD risk.

CONCLUSIONS

SBII provides higher sensitivity when evaluating OSA severity and better predictive capabilities for CVD outcomes. SBII may be a more effective substitute for AHI in the future.

CITATION

Dai L, Cao W, Luo J, Huang R, Xiao Y. The effectiveness of sleep breathing impairment index in assessing obstructive sleep apnea severity. J Clin Sleep Med. 2023;19(2):267-274.

Association of alternative polysomnographic features with patient outcomes in obstructive sleep apnea: a systematic review

STUDY OBJECTIVES

Polysomnograms (PSGs) collect a plethora of physiologic signals across the night. However, few of these PSG data are incorporated into standard reports, and hence, ultimately, under-utilized in clinical decision making. Recently, there has been substantial interest regarding novel alternative PSG metrics that may help to predict obstructive sleep apnea (OSA)-related outcomes better than standard PSG metrics such as the apnea-hypopnea index. We systematically review the recent literature for studies that examined the use of alternative PSG metrics in the context of OSA and their association with health outcomes.

METHODS

We systematically searched EMBASE, MEDLINE, and the Cochrane Database of Systematic Reviews for studies published between 2000 and 2022 for those that reported alternative metrics derived from PSG in adults and related them to OSA-related outcomes.

RESULTS

Of the 186 initial studies identified by the original search, data from 31 studies were ultimately included in the final analysis. Numerous metrics were identified that were significantly related to a broad range of outcomes. We categorized the outcomes into 2 main subgroups: (1) cardiovascular/metabolic outcomes and mortality and (2) cognitive function- and vigilance-related outcomes. Four general categories of alternative metrics were identified based on signals analyzed: autonomic/hemodynamic metrics, electroencephalographic metrics, oximetric metrics, and respiratory event-related metrics.

CONCLUSIONS

We have summarized the current landscape of literature for alternative PSG metrics relating to risk prediction in OSA. Although promising, further prospective observational studies are needed to verify findings from other cohorts, and to assess the clinical utility of these metrics.

CITATION

Hajipour M, Baumann B, Azarbarzin A, et al. Association of alternative polysomnographic features with patient outcomes in obstructive sleep apnea: a systematic review. J Clin Sleep Med. 2023;19(2):225-242.

Upper Airway Stimulation Therapy Effect on Blood Pressure

OBJECTIVE

Upper airway stimulation (UAS) therapy has become increasingly utilized to treat obstructive sleep apnea, which is an independent risk factor for the development of hypertension. This study examines the impact of this therapy on blood pressure (BP).

STUDY DESIGN

Retrospective cross-sectional cohort study.

SETTING

Tertiary center, Military Health System.

METHODS

Patients who underwent UAS implantation at Brooke Army Medical Center between July 2015 and July 2020 were included if they used their device for at least 25 h/wk. Pre- and postoperative systolic BP, diastolic blood pressure (DBP), calculated mean arterial pressure (MAP), and the apnea-hypopnea index (AHI) were compared using paired t test or Wilcoxon's signed-rank test.

RESULTS

Thirty patients met the inclusion criteria. The median age was 60, and the median body mass index was 29.9 kg/m² . The mean time between pre- and postoperative BP measurements was 11.6 months. AHI decreased from 35.1 to 16.5 events/h (p < .001). DBP decreased from 78.5 (73.8, 85.0) to 74.5 mm Hg (68.8, 81.3), with a mean difference of -3.7 mm Hg (p = .002). MAP decreased from 94.8 (89.6, 100.6) to 90.2 mm Hg (84.3, 100.0), with a mean difference of -3.7 mm Hg (p = .004).

CONCLUSION

UAS therapy was associated with a significant reduction in DBP, MAP, and AHI. These reductions in BP could potentially lead to favorable decreases in cardiovascular morbidity.

Clinical and functional characteristics of OSA in children with comorbid asthma treated by leukotriene receptor antagonist: A descriptive study

Background

Obstructive sleep apnea (OSA) is the most common form of respiratory disorders during sleep in children, especially those with severe asthma. However, optimal treatment of asthma might significantly improve OSA severity.

Methods

It was a cohort study including children aged >5 years old and diagnosed with asthma according to GINA (Global Initiative for Asthma). The data related to age, gender, height, weight, body mass index (BMI), clinical symptoms and medical history of asthma, spirometry (FEV₁: forced expiratory in 1 s), and exhaled nitric oxide (F_ENO) were recorded for analysis. Respiratory polygraphy (RPG) was done for each study subject to diagnose OSA and its severity.

Results

Among 139 asthmatic children, 99 patients with OSA (71.2%) were included in the present study (9.3 ± 0.2 years): 58.6% with uncontrolled asthma and 32.3% with partial controlled asthma. The mean ACT (asthma control testing) score was 19.0 ± 3.4. The most frequent night-time symptoms were restless sleep (76.8%), snoring (61.6%), sweating (52.5%), and trouble breathing during sleep (48.5%). The common daytime symptoms were irritable status (46.5%) and abnormal behavior (30.3%). The mean AHI (apnea-hypopnea index) was 3.5 ± 4.0 events/h. There was a significant correlation between BMI and snoring index (R = 0.189 and P = 0.027), bronchial and nasal F_ENO with AHI (R = 0.046 and P < 0.001; R = 0.037 and P < 0.001; respectively). There was no significant correlation between asthma level, FEV₁ and AHI. The severity of asthma and respiratory function were improved significantly after 3 months and 6 months of asthma treatment in combination with leukotriene receptor antagonist (LRA) treatment. The symptoms related to OSA were significantly improved after treatment with LRA. The severity of OSA was decreased significantly after 3 months and 6 months of treatment.

Conclusion

The treatment of asthmatic children with comorbid OSA by LRA in combination with standard therapy for asthma could improve the control of asthma and the symptoms and severity of OSA.

[Optimization of laser exposure parameters during surgical correction of soft palate tissues in patients with ronchopathy and obstructive sleep apnea syndrome]

OBJECTIVE

Substantiation of optimization of laser radiation parameters when performing surgery on the soft palate to improve the results of treatment of patients with ronchopathy and obstructive sleep apnea syndrome.

MATERIAL AND METHODS

Based on the experience of performing laser sculptural uvulopalatoplasty in 309 patients with ronchopathy and obstructive sleep apnea syndrome, a rational choice of parameters of laser radiation used during the operation is justified.

RESULTS

Optimization of laser radiation parameters during laser sculptural uvulopalatoplasty allowed to improve the positive results of treatment of patients with ronchopathy and obstructive sleep apnea syndrome in 98.4% of cases (304 out of 309 operated patients).

CONCLUSION

Optimization of laser radiation parameters when performing laser sculptural uvulopalatoplasty increases the effectiveness of treatment of patients with ronchopathy and obstructive sleep apnea syndrome.

Disturbed Sleep is Not Good for the Heart: A Narrative Review

Sleep-related breathing disorders, including obstructive sleep apnea (OSA) and central sleep apnea (CSA), have a major impact on cardiovascular function. It has shown an association with hypertension, coronary artery disease, cardiac arrhythmias, sudden cardiac death, and congestive heart failure (CHF). This review focuses on highlighting the relationship between sleep apnea and CHF. We discuss the underlying pathophysiology, which involves the mechanical, neurohormonal, and inflammatory mechanisms; in addition, the similarities and differentiating clinical features of OSA in patients with CHF and without CHF. We have also discussed several treatment strategies, including weight loss, continuous positive airway pressure (CPAP), supplemental oxygen therapy, theophylline, acetazolamide, mandibular advancement device, and hypoglossal nerve stimulation (HGNS). We conclude that since there are several overlapping clinical features in patients with OSA with Heart Failure (HF) and without HF, early detection and treatment are crucial to decrease the risk of HF, coronary artery disease, and stroke.

An evaluation of cone beam computed tomography in verifying the level of collapse in obstructive sleep apnea patients

OBJECTIVE

To assess the accuracy of cone beam computed tomography (CBCT) in verifying the level of collapse in obstructive sleep apnea (OSA) patients.

METHODS

A prospective analysis of 30 patients with confirmed OSA was selected. Drug-induced sleep endoscopy (DISE) was performed for all cases to determine the level of collapse clinically. Two groups of patients were imaged with CBCT, one at end of expiration and the other at end of inspiration. Virtual endoscopy was performed on CBCT software. The level of collapse was recorded from both groups and compared to DISE findings.

RESULTS

No statistical difference was discovered in the level of collapse observed from DISE or CBCT in most cases. Virtual endoscopy was found to have no role in determining collapse at tongue and lateral wall levels.

CONCLUSION

Using CBCT helped predict the air blockage level in patients with sleep apnea, which helps in surgical treatment planning measures.

The Effects of Changing Continuous Positive Airway Pressure Devices in Japanese Patients with Obstructive Sleep Apnea: A Case Series

Background The effects of continuous positive airway pressure (CPAP) devices on obstructive sleep apnea (OSA) in Japanese patients have not been reported. We assessed the effects of changing CPAP devices (from the Philips Respironics device to the ResMed device) on the control of OSA. Methods We retrospectively examined 13 patients with OSA who voluntarily changed from the Philips Respironics device to the ResMed device due to a Philips Respironics CPAP device recall. Data on the apnea-hypopnea index (AHI) were obtained from the CPAP devices for three months before and after changing the devices. Results The AHI obtained from the CPAP devices significantly decreased from 4.4 (3.1-10.7) events/h to 2.0 (0.8-3.6) events/h when patients changed devices (P=0.022). The AHI decreased to <5 events/h after changing devices in 4 patients, whereas it had been ≥5 events/h before changing devices in 6 patients. Conclusion Changing CPAP devices can decrease the AHI.

Body weight and obstructive sleep apnea: a mathematical relationship between body mass index and apnea-hypopnea index in veterans

STUDY OBJECTIVES

A high body mass index (BMI) is a risk factor for obstructive sleep apnea. However, to our knowledge there is no reported equation that quantifies the relationship between weight, as measured by BMI, and apnea severity, as assessed by the apnea-hypopnea index (AHI). Our objective was to find a mathematical relationship between BMI and AHI.

METHODS

We prospectively recruited 434 veterans from our polysomnography laboratory. Veterans already undergoing a sleep study were approached, and those who consented were enrolled. The veterans who enrolled in our study also participated in their scheduled sleep study. This study was approved by our institutional review board.

RESULTS

We found a simple mathematical relationship between BMI and AHI: for every 1-point drop in BMI (corresponding to 5-8 pounds, depending on a person's height), AHI decreases by 6.2%. And limiting BMI to 25-40 kg/m2 (which includes about 80% of the BMIs), then AHI drops by 7.1%. Simply put as a rule of thumb: For every 7-pounds drop in weight, expect a 7% drop in AHI.

CONCLUSIONS

To our knowledge, this is the first simple mathematical equation that associates the severity of weight with the severity of apnea in veterans. This equation can be a practical rule of thumb that can be implemented in clinics to predict the amount of weight a patient needs to lose to decrease their apnea, which might help motivate patients to lose weight.

CITATION

Fattal D, Hester S, Wendt L. Body weight and obstructive sleep apnea: a mathematical relationship between body mass index and apnea-hypopnea index in veterans. J Clin Sleep Med. 2022;18(12):2723-2729.

Risk factors of left ventricular hypertrophy in obstructive sleep apnea

Obstructive sleep apnea (OSA) and left ventricular hypertrophy (LVH) are both related to major cardiovascular diseases. Previous studies have indicated that, compared with non-OSA, OSA is related to LVH with an odds ratio (OR) of 1.70 (95% CI: 1.44-2.00), particularly in patients with coronary artery disease. Meta-analysis has revealed that the severity of OSA is significantly associated with left ventricular mass compared with non-OSA controls. There is, however, limited data on the risk factors of LVH in patients with OSA. The present study aimed to assess the prevalence and clinical factors that are predictive of LVH in patients with OSA. A retrospective analysis of adult patients diagnosed with OSA who had undergone echocardiography was performed. LVH defined by echocardiography indicated an enlarged LV mass index. Clinical factors predictive of LVH were assessed using multivariate logistic regression analyses. An unadjusted OR and an adjusted OR with 95% confidence intervals (CI) were determined. During the study period, 130 patients met the study criteria, with an LVH prevalence of 27.69% (36 patients). The final predictive model of LVH comprised six factors: Age, sex, unrefreshed sleep, body mass index, systolic blood pressure and apnea-hypopnea index. Only age was independently associated with LVH, with an adjusted OR of 1.048 (95% CI: 1.002-1.096). The prevalence rate of LVH in patients with OSA was 27.69%. Older age was independently related to LVH in patients with OSA.

Does race-ethnicity affect upper airway stimulation adherence and treatment outcome of obstructive sleep apnea?

STUDY OBJECTIVES

Untreated obstructive sleep apnea (OSA) is associated with excessive daytime sleepiness, decreased quality of life, and cardiovascular disease. Positive airway pressure is the first-line therapy for OSA; however, adherence is difficult. Upper airway stimulation is a Food and Drug Administration-approved treatment of OSA. The objective of this study was to evaluate for a difference in treatment efficacy and adherence of upper airway stimulation therapy for OSA between individuals who are White and non-White using data from the ADHERE registry.

METHODS

ADHERE registry is a multicenter prospective study of real-world experience of upper airway stimulation for treatment of OSA in the United States and Europe. Propensity score matching was used to create a balanced dataset between the White and non-White groups. t-Tests at a significance level of 5% were used to compare numeric values between groups.

RESULTS

There were 2,755 participants of the ADHERE registry: 27 were excluded due to not having a race identified, 125 participants identified as non-White, 2,603 identify as White, and 27 did not provide race information. Propensity score matching was used to select 110 participants, with 55 White and 55 non-White for the noninferiority analysis. We did not find a difference in adherence, treatment apnea-hypopnea index, changes in Epworth Sleepiness Scale score, or clinical global impression after intervention score between White and non-White individuals.

CONCLUSIONS

Our study found that there was no statistically significant difference in adherence or efficacy with upper airway stimulation therapy between White and non-White individuals. However, the percent of non-White people implanted is low, which suggests a need to expand access to this therapy for non-White populations with OSA who cannot tolerate positive airway pressure therapy.

CITATION

Khan M, Stone A, Soose RJ, et al. Does race-ethnicity affect upper airway stimulation adherence and treatment outcome of obstructive sleep apnea? J Clin Sleep Med. 2022;18(9):2167-2172.

Alveolar Ventilation-Targeted Versus Spontaneous/Timed Mode for Home Noninvasive Ventilation in Amyotrophic Lateral Sclerosis

BACKGROUND

Home noninvasive ventilation (NIV) is increasingly used in amyotrophic lateral sclerosis (ALS) to improve symptoms and survival. Our primary objective was to compare intelligent volume-assured pressure support (iVAPS) versus spontaneous/timed (S/T) modes regarding time to first change in ventilator parameters and the number of interventions over 6 months in subjects with ALS in a respiratory therapist (RT)-led program.

METHODS

In this study, 30 subjects with ALS meeting criteria for NIV initiation were randomized to iVAPS or S/T. NIV was initiated using standardized protocols targeting optimal tidal volume and comfort in a daytime session. Download data were recorded at 1 week and 1 and 6 months. Any changes in ventilator parameters were recorded.

RESULTS

Of the 30 subjects, 56.7% had bulbar onset ALS, 8 died, and 11 in each group completed the study. Median time to first parameter change was 33.5 (interquartile range [IQR] 7.7-96.0) d versus 41.0 (IQR 12.5-216.5) d for iVAPS versus S/T groups, respectively, (P = .48). The average number of RT interventions was similar between groups (1.1 ± 1.1 vs 0.9 ± 0.9 at 1 month, P = .72; 2.4 ± 2.1 vs 2.4 ± 2.3 at 6 months, P = .95, for iVAPS vs S/T, respectively). Adherence was significantly lower with iVAPS than S/T at 1 week but not at 1 or 6 months. Download parameters were similar between groups at 1 week and 6 months except for higher residual apnea-hypopnea index (AHI) and less spontaneously triggered breaths with iVAPS at 6 months.

CONCLUSIONS

The time to first change of parameters and the number of interventions at 6 months from NIV initiation were similar for the iVAPS and S/T modes in subjects with ALS. With iVAPS, adherence was lower transiently at NIV initiation, and the residual AHI was higher at 6 months. Alveolar ventilation-targeted NIV may require a longer adaptation period and result in greater upper-airway instability predominantly in patients with bulbar ALS.

Correlation of cephalometric variables with obstructive sleep apnea severity among children: a hierarchical regression analysis

OBJECTIVE

To evaluate the correlation between cephalometric parameters and apnea-hypopnea index (AHI) after controlling gender, body mass index (BMI), and adenoid size in children with obstructive sleep apnea (OSA).

METHODS

Sixty-four children with OSA (40 males, 24 females, 8.72 ± 0.899 years) were chosen by simple random sampling for a cross-sectional study from January 2018 to March 2022. They were diagnosed with OSA, assessed by Obstructive Sleep Apnea-18 questionnaire and home polysomnography and underwent lateral cephalograms.

RESULTS

Hierarchical regression analysis indicated that cephalometric parameters (except adenoid size) were associated with OSA severity, explaining 18.1% of the AHI variance. Among cephalometric measurements, AHI was positively associated with H-RGn and N-Go-Me angle (p < 0.05) and negatively associated with NP (p < 0.05).

CONCLUSION

The sagittal diameter of the oropharynx, lower gonial angle, and hyoid position are significant AHI predictors in children with OSA, independent of demographic characteristics and adenoid size.

The Sleep Revolution project: the concept and objectives

Obstructive sleep apnea is linked to severe health consequences such as hypertension, daytime sleepiness, and cardiovascular disease. Nearly a billion people are estimated to have obstructive sleep apnea with a substantial economic burden. However, the current diagnostic parameter of obstructive sleep apnea, the apnea-hypopnea index, correlates poorly with related comorbidities and symptoms. Obstructive sleep apnea severity is measured by counting respiratory events, while other physiologically relevant consequences are ignored. Furthermore, as the clinical methods for analysing polysomnographic signals are outdated, laborious, and expensive, most patients with obstructive sleep apnea remain undiagnosed. Therefore, more personalised diagnostic approaches are urgently needed. The Sleep Revolution, funded by the European Union's Horizon 2020 Research and Innovation Programme, aims to tackle these shortcomings by developing machine learning tools to better estimate obstructive sleep apnea severity and phenotypes. This allows for improved personalised treatment options, including increased patient participation. Also, implementing these tools will alleviate the costs and increase the availability of sleep studies by decreasing manual scoring labour. Finally, the project aims to design a digital platform that functions as a bridge between researchers, patients, and clinicians, with an electronic sleep diary, objective cognitive tests, and questionnaires in a mobile application. These ambitious goals will be achieved through extensive collaboration between 39 centres, including expertise from sleep medicine, computer science, and industry and by utilising tens of thousands of retrospectively and prospectively collected sleep recordings. With the commitment of the European Sleep Research Society and Assembly of National Sleep Societies, the Sleep Revolution has the unique possibility to create new standardised guidelines for sleep medicine.

Red blood cell distribution width in Obstructive Sleep Apnea Syndrome and its association with cardiovascular disease

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular disease (CVD). Red blood cell distribution width (RDW) is reported as a novel marker of cardiovascular disease (CVD) risk. We aimed to investigate the correlation of RDW level with the severity of Obstructive Sleep Apnea Syndrome (OSAS) defined with the apnea-hypopnea index (AHI) and to study the relationship between RDW and CVD in OSAS.

METHODS

From retrospective analyses of patients admitted to our department for polygraphy between January 2018 and January 2020, OSAS patients with complete medical records and hemogram analyses were evaluated.

RESULTS

The study population consisted of 160 patients (101 females/59 males). The mean age was 52.32 ± 10.83 years. RDW correlated positively with the apnea hypopnea index (AHI) (r=0.392; p < 0.0001) and C-reactive protein (CRP) (r = 0.3, p < 0.001). RDW and CRP were significantly higher in patients with CVD than whom without CVD (p < 0.0001). In multivariate analysis, the independent predictors of CVD in OSAS were RDW (p < 0.0001; OR=3.095; CI: 1.69-5.66), CRP (p=0.046; OR=1.136; CI: 1.002-1.287) and age (p=0.013; OR=1.085; CI: 1.017- 1.157). The cut-off level for RDW with optimal sensitivity and specificity was calculated as 14.45 with sensitivity of 81% and specificity of 75%.

CONCLUSIONS

The findings of this study suggest that RDW, a simple, relatively inexpensive and universally available marker could have the ability to predict CVD in OSAS.

[Effects of Obstructive Sleep Apnea and Gender on Glomerular Filtration Rate in Hypertensive Population]

Objective To explore the associations of obstructive sleep apnea(OSA) and gender with estimated glomerular filtration rate(eGFR) in hypertensive populations.Methods From February 2005 to August 2010,2064 hypertensive patients who were treated in the Department of Hypertension Center underwent overnight polysomnographic monitoring.According to the apnea-hypopnea index(AHI),they were assigned into an hypertension combined with OSA group and a hypertension group.The clinical characteristics and sleep monitoring indicators were compared between different genders and between the two groups.Multivariate Logistic regression was employed to analyze the influencing factors of eGFR.Results Among the 2064 hypertensive patients,there were 1537 males(including 1221 patients with OSA) and 527 females(including 350 patients with OSA).The males had higher prevalence of OSA(χ²=36.631,P<0.001) and diastolic blood pressure(Z=-7.776,P<0.001) and lower eGFR(Z=-3.010,P=0.003) than the females.The males had higher AHI(Z=-8.727,P<0.001),apnea index(Z=-9.252,P<0.001),hypopnea index(HI)(Z=-4.868,P<0.001) than the females,and the lowest oxygen saturation(t=-3.325,P=0.001) was significantly lower in males than in females.The hypertension combined with OSA group showed lower eGFR than the hypertension group(Z=-27.434,P<0.001;Z=-18.762,P<0.001).HI was negatively correlated with eGFR in the male population(r=-0.006,P=0.017),and AHI and HI were negatively correlated eGFR in females(r=-0.108,P=0.013;r=-0.094,P=0.032).After adjustment,Logistic regression showed that OSA and oxygen desaturation index 4 were the risk factors for the reduction of eGFR in hypertensive patients in males and females,respectively(OR=1.383,95%CI=1.010-1.905,P=0.045;OR=1.013,95%CI=1.002-1.024,P=0.021).Conclusion OSA lowers the eGFR of hypertensive patients,and OSA and oxygen desaturation index are the risk factors for the decrease in eGFR in male and female hypertensive patients,respectively.

Effects of Vagus Nerve Stimulation on Sleep-Disordered Breathing, Daytime Sleepiness, and Sleep Quality in Patients With Drug-Resistant Epilepsy

Background and Purpose

This study aimed to determine the long-term effects of vagus nerve stimulation (VNS) on sleep-disordered breathing (SDB), daytime sleepiness, and sleep quality in patients with drug-resistant epilepsy (DRE). It also investigated the relationships among these main effects, clinical characteristics, and VNS parameters.

Methods

Twenty-four patients were recruited. Paired t-tests and multiple linear regression analyses were performed to determine how the demographic and clinical characteristics of the patients influenced the variables that changed significantly after VNS treatment.

Results

After VNS, the patients showed significant increases in the apnea-hypopnea index (AHI), respiratory disturbance index (RDI), apnea index, hypopnea index, and oxygen desaturation index (ODI), as well as a significant decrease in the lowest arterial oxygen saturation (SaO₂ nadir) (p<0.05). The multiple linear regression analyses demonstrated that the predictor of larger increases in AHI and RDI was being older at baseline, and that the predictor of a larger increase in apnea index was a longer epilepsy duration. The strongest predictor of a larger increase in ODI was a higher frequency of aura episodes at baseline, followed by a longer epilepsy duration. The strongest predictor of a larger decrease in SaO₂ nadir was a higher frequency of aura episodes at baseline, followed by a longer epilepsy duration.

Conclusions

This study has confirmed that VNS improves seizure control in patients with DRE, whereas it increases obstructive sleep apnea (OSA). Furthermore, the increase in OSA is affected by age and the duration of epilepsy. Therefore, careful observation and monitoring of SDB is recommended in patients who undergo VNS.

Impaired Glymphatic System Actions in Obstructive Sleep Apnea Adults

Study Objectives

Obstructive sleep apnea (OSA) is accompanied by sleep fragmentation and altered sleep architecture, which can potentially hinder the glymphatic system, increasing risks for Alzheimer's disease (AD), but the status is unclear in OSA. Our aim was to investigate the glymphatic system in OSA subjects and examine the relationships between OSA disease severity, sleep symptoms, and glymphatic system indices in OSA using diffusion tensor imaging (DTI).

Methods

We acquired DTI data from 59 OSA and 62 controls using a 3.0-Tesla MRI and examined OSA disease severity and sleep symptoms with the Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). Diffusivity maps in the x-axis (Dxx), y-axis (Dyy), and z-axis (Dzz), as well as in x-y axis (Dxy), y-z axis (Dyz), and x-z axis (Dxz) were calculated, diffusion values for the projection and association fibers extracted, and the DTI analyses along the perivascular space (DTI-ALPS index) were performed. The glymphatic system indices were compared between groups and correlated with disease severity and sleep symptoms in OSA subjects.

Results

Dzz values, derived from projection fiber areas, Dyy and Dzz values from association fiber areas, as well as ALPS and Dyzmean values were significantly reduced in OSA over controls. Significant correlations emerged between disease severity, sleep symptoms, and Dxy, Dxx, and Dzz values in OSA subjects.

Conclusion

OSA patients show abnormal glymphatic system function that may contribute to increased risks for AD. The findings suggest that the APLS method can be used to assess the glymphatic system in OSA patients.

Association of obstructive sleep apnea and nocturnal hypoxemia with all-cancer incidence and mortality: a systematic review and meta-analysis

STUDY OBJECTIVES

Biological models suggest that obstructive sleep apnea (OSA) is potentially carcinogenic. We aimed to clarify the inconsistent epidemiological literature by considering various traditional and novel OSA severity indices.

METHODS

We systematically searched PubMed, Embase, Scopus, and the Cochrane Library for observational or randomized studies of associations of OSA, measured by diagnostic codes or any index, each with all-cancer incidence or mortality in adults, compared with participants with no/mild OSA. Two reviewers independently selected studies, extracted data, and evaluated study bias using the Newcastle-Ottawa scale and quality of evidence using GRADE (Grading of Recommendations Assessment, Development, and Evaluation). We performed inverse variance-weighted, random-effects meta-analyses and sensitivity analyses.

RESULTS

We included 20 observational studies (5,340,965 participants), all with moderate/low bias, from 1,698 records. Based on T90 (sleep duration with oxygen saturation < 90%), patients with OSA who had moderate (T90 > 1.2%, hazard ratio [HR] = 1.28, 95% confidence interval [CI] = 1.07-1.54) and severe nocturnal hypoxemia (T90 > 12%, HR = 1.43, 95% CI = 1.16-1.76) experienced 30%-40% higher pooled all-cancer risk than normoxemic patients, after multiple adjustment for covariates including obesity. Furthermore, severe nocturnal hypoxemia nearly tripled all-cancer mortality (HR = 2.66, 95% CI = 1.21-5.85). Patients with apnea-hypopnea index-defined severe OSA, but not moderate OSA, had higher all-cancer risk (HR = 1.18, 95% CI = 1.03-1.35) but similar all-cancer mortality as patients without OSA. An OSA diagnosis was not associated with all-cancer risk. Evidence quality ranged from low to moderate. Insufficient evidence was available on the oxygen desaturation index, lowest/median saturation, and arousal index.

CONCLUSIONS

In patients with OSA, nocturnal hypoxemia is independently associated with all-cancer risk and mortality. Future studies should explore if risk differs by cancer type, and whether cancer screening and OSA treatment are beneficial.

SYSTEMATIC REVIEW REGISTRATION

Registry: PROSPERO; URL: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=220836; Identifier: CRD42021220836.

CITATION

Tan BKJ, Teo YH, Tan NKW, et al. Association of obstructive sleep apnea and nocturnal hypoxemia with all-cancer incidence and mortality: a systematic review and meta-analysis. J Clin Sleep Med. 2022;18(5):1427-1440.

Dose-response relationship between weight loss and improvements in obstructive sleep apnea severity after a diet/lifestyle interventions: secondary analyses of the "MIMOSA" randomized clinical trial

STUDY OBJECTIVES

Lifestyle-induced weight loss is a complementary therapeutic approach for obstructive sleep apnea (OSA). We aimed at identifying the dose-response relationship between weight loss and OSA severity improvement.

METHODS

This is a secondary analysis of a 6-month clinical trial in 180 adult, overweight/obese moderate-to-severe OSA patients. Participants were randomized to a standard care, a Mediterranean diet, or a Mediterranean lifestyle arm. All patients were prescribed with continuous positive airway pressure (CPAP), while intervention arms additionally participated in a weight-loss dietary/lifestyle intervention. Based on percent change in weight at 6 months, participants were categorized into a weight-stable/gain (WS/GG) group or 3 weight-loss groups (WLG): < 5%WLG, 5%-10%WLG, and ≥ 10%WLG. Polysomnographic data and OSA symptoms were evaluated preintervention and postintervention.

RESULTS

Respiratory events and oximetry indices improved only in patients who lost weight and improvements were proportional to the degree of weight loss. Median percent change in apnea-hypopnea index (AHI) was -11.7%, - 37.9%, and - 49.3% in the < 5%WLG, 5%-10%WLG, and ≥ 10%WLG, respectively (P < .001). Compared to the WS/GG, the age-, sex-, baseline-, and CPAP use-adjusted relative risk (95% confidence interval) of severe OSA (AHI ≥ 30 events/h) was 0.45 (0.23-0.87) in the 5%-10%WLG and 0.32 (0.17-0.64) in the ≥ 10%WLG; the risk was also lower in the ≥ 10%WLG vs the < 5%WLG (0.42 [0.22-0.82]). Insomnia and daytime sleepiness also improved more in participants exhibiting ≥ 5% weight loss.

CONCLUSIONS

Even a < 5% weight loss can reduce respiratory events, but a ≥ 5% and ideally ≥ 10% weight loss is necessary for reducing the prevalence of severe OSA.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Mediterranean Diet/Lifestyle Intervention in Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/NCT02515357; Identifier: NCT02515357.

CITATION

Georgoulis M, Yiannakouris N, Kechribari I, et al. Dose-response relationship between weight loss and improvements in obstructive sleep apnea severity after a diet/lifestyle intervention: secondary analyses of the "MIMOSA" randomized clinical trial. J Clin Sleep Med. 2022;18(5):1251-1261.

Obstructive sleep apnea in children with non-syndromic cleft palate: a systematic review

STUDY OBJECTIVES

To characterize obstructive sleep apnea (OSA) in children with non-syndromic cleft palate based on polysomnographic parameters relative to primary palatoplasty.

METHODS

A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The following databases were searched: PubMed, Scopus, CINAHL, and Cochrane. Studies were only considered for inclusion if they examined exclusively non-syndromic cleft palate patients and reported polysomnogram data.

RESULTS

Seven studies met inclusion criteria, providing information on a total of 151 patients with a weighted mean age of 5.2 ± 5.0 years old (range 0.1- 12 years). Five studies presented data from either the pre- or post-operative period. Two studies investigated both pre- and post-palatoplasty polysomnogram data, and neither observed a significant change in apnea hypopnea index (AHI) values following surgery (mean pre-operative AHI of 2.7, mean improvement of 0.6 events/hour). The entire cohort had a pre-palatoplasty weighted mean AHI of 11.4 (range 1.5 -16.1) and post-palatoplasty AHI of 1.5 (range 0.2 - 5.2). Interpretation of polysomnographic data was limited by heterogeneity; however, the AHI values of children with non-syndromic cleft palate largely demonstrated mild to moderate OSA following palatoplasty.

CONCLUSIONS

The full effect of cleft palate repair on OSA in children with non-syndromic cleft palate remains understudied. While published data are heterogenous, few studies support the worsening of obstructive AHI after palatoplasty in children with non-syndromic cleft palate. Further studies with standardized polysomnographic parameters are needed to provide guidance for management of this population.

Effects of Sacubitril-Valsartan on Clinical, Echocardiographic, and Polygraphic Parameters in Patients Affected by Heart Failure With Reduced Ejection Fraction and Sleep Apnea

Background

Heart failure with reduced ejection fraction (HFrEF) is a clinical condition frequently diagnosed in clinical practice. In patients affected by HFrEF, sleep apnea (SA) can be detected among the most frequent comorbidities. Sacubitril–valsartan (sac/val) association has been proven to be effective in reducing disease progression and all-cause mortality in HFrEF patients. Sac/val treatment can potentially attenuate SA development via several pathophysiologic mechanisms, including improvement of global hemodynamics, reduction of extracellular fluid overload, and decrease of sympathetic neural activity.

Methods

We recruited 132 patients affected by HFrEF and SA, already under treatment with continuous positive airway pressure (CPAP), which was discontinued 24 h before the scheduled study timepoints. Physical examination, echocardiography, nocturnal cardio-respiratory monitoring, and laboratory tests were performed in each patient at baseline and after a 6-month treatment with sac/val.

Results

After 6 months, sac/val induced statistically significant changes in clinical, hemodynamic, biohumoral (NT-proBNP, serum electrolytes, creatinine, and uric acid), and echocardiographic parameters. In particular, cardiac index (CI), both atrial and ventricular volumes and global longitudinal strain (GLS) improved. Moreover, polysomnography, carried out during a temporary CPAP interruption, revealed a significant reduction in global apnea-hypopnea index (AHI) value (p < 0.0001), central AHI (p < 0.0001), obstructive AHI (p < 0.0001), oxygen desaturation index (ODI) (p < 0.0001), and percentage time of saturation below 90% (TC90) (p < 0.0001). The changes of CI, estimated glomerular filtration rate (eGFR), NT-proBNP, and tricuspid annular plane excursion (TAPSE) contributed to 23.6, 7.6, 7.3, and 4.8% of AHI variability, respectively, and the whole model accounted for a 43.3% of AHI variation.

Conclusions

Our results suggest that treatment with sac/val is able to significantly improve the cardiorespiratory performance of patients with HFrEF and SA, integrating the positive impact of CPAP. Thus, both CPAP and sac/val therapy may synergistically contribute to lower the risks of both cardiac and pulmonary complications in HFrEF patients with SA.