Sleep and Breathing

Chapleau, Richard R.; Regn, Dara D.

doi: 10.1007/s11325-021-02427-8pmid: 34231084

PurposeObstructive sleep apnea (OSA) is the most common pathologic sleep disorder with an estimated prevalence in the USA of up to 25% of adult males. With military aviation being heavily comprised of adult men, the impact of OSA on flying operations is concerning as OSA is disqualifying for all flying classes in the US Air Force. In order to minimize the impact of OSA on operations, early identification of at-risk patients is critical in disease management. Individuals could be identified for whom regular polysomnography testing may reveal OSA while mild or sub-clinical, at which point treatment may be initiated in order to promote continued medical qualification for duty and career retention.MethodsWe performed a keyword search of PubMed, EMBASE, and Google Scholar along with searches in the NHGRI/EBI GWAS Catalogue and the Atlas of GWAS Summary Statistics. We included primary research from candidate gene, GWAS, and meta-analyses. We also included other review articles in our search to confirm interpretations and implications of any genetic associations with OSA. Only studies related to OSA susceptibility or risk were included.ResultsWe identified 134 publications reporting or reviewing genetic associations with OSA risk. These papers reported 301 variants, of which 195 were unique and 33 were replicated in at least two papers. With respect to the strength of association, 43 variants exhibited odds ratios greater than 2. Finally, there were 84 null results reported, 51 of which were in conflict with reported associations.ConclusionThere is ample evidence in the literature to confirm that genetics provide an important contribution to OSA development. The high number of strongly associated variants suggests that a polygenic risk model could be created with high predictive value for prognostic screening.

Antonaglia, Caterina; Passuti, Giovanna

doi: 10.1007/s11325-021-02412-1pmid: 34324126

Obstructive sleep apnea syndrome (OSAS) is characterized by symptoms and signs of more than 5 apneas per hour (AHI) at polysomnography or 15 or more apneas per hour without symptoms. In this review, the focus will be a subgroup of patients: adult non-obese subjects with OSA and their specific features. In non-obese OSA patients (patients with BMI < 30 kg/m2), there are specific polysomnographic features which reflect specific pathophysiological traits. Previous authors identified an anatomical factor (cranial anatomical factors, retrognatia, etc.) in OSA non-obese. We have hypothesized that in this subgroup of patients, there could be a non-anatomical pathological prevalent trait. Little evidence exists regarding the role of low arousal threshold. This factor could explain the difficulty in treating OSA in non-obese patients and emphasizes the importance of a specific therapeutic approach for each patient.

Chen, Huimin; Zheng, Zhenzhen; Chen, Riken; Zeng, Yu; Li, Nanhong; Zhu, Jinru; Zhong, Yue; Liu, Haimin; Lu, Jianmin; Zhang, Nuofu; Hong, Cheng

doi: 10.1007/s11325-021-02410-3pmid: 34106436

Sunkonkit, Kanokkarn; Selvadurai, Sarah; Voutsas, Giorge; Benzon, David; Baker, Adele; Trinh, Melissa; Narang, Indra

doi: 10.1007/s11325-021-02409-wpmid: 34105105

PurposeTo evaluate the impact of the COVID-19 pandemic on non-invasive positive airway pressure (PAP) usage among children with sleep-disordered breathing (SDB).MethodsPAP usage data in children with SDB aged 1 to 18 years old at The Hospital for Sick Children, Canada, were analyzed. The PAP usage data were recorded for 3 months prior to and 3 months following the COVID-19 lockdown in Ontario, Canada. The primary outcomes of interest were (i) percentage of days that PAP was used for ≥ 4 h and (ii) average daily usage of PAP based on days when PAP was used.ResultsA total of 151 children were included. The mean (± SD) age and BMI were 12.6 ± 4.1 years and 28.7 ± 12.4 kg/m2, respectively. The median (IQR) percentage of days of PAP usage for ≥ 4 h and average nightly PAP usage was significantly higher during compared with prior to the pandemic (76.7 [19.0–94.0] vs 62.0 [15.5–89.0]%, p = 0.02, and 406.0 [244.0–525.0] vs 367.0 [218.0–496.0] min, p = 0.006, respectively). Within this cohort, 95/151 (63%) children with SDB showed increased PAP usage and 56/151 (37%) either decreased the amount of time they used PAP or stopped PAP use altogether.ConclusionsCOVID-19 pandemic has provided opportunities for increased PAP usage in a significant number of children with SDB. A subset of children with prior evidence for suboptimal PAP usage showed further decreases in PAP usage during the pandemic. This information is critical for clinicians to provide anticipatory guidance to encourage PAP usage both during the pandemic and beyond.

Adami, Alessandro; Tonon, Davide; Corica, Antonio; Trevisan, Deborah; Cipriano, Giovanni; De Santis, Nicoletta; Guerriero, Massimo; Rossato, Gianluca

doi: 10.1007/s11325-021-02414-zpmid: 34136978

PurposeScreening commercial drivers (CDs) for obstructive sleep apnea (OSA) reduces the risk of motor vehicle accidents. We evaluated the accuracy of standard OSA questionnaires in a cohort of CDs.Study design and methodsWe enrolled consecutive male CDs at 10 discrete transportation companies during their yearly scheduled occupational health visit. The CDs had their anthropometric measures taken; completed the Berlin, STOP, STOP-BANG, OSAS-TTI, SACS, EUROSAS, and ARES questionnaires; and underwent a home sleep apnea test (HSAT) for the determination of their respiratory events index (REI). We assessed the questionnaires’ ability to predict OSA (REI ≥ 5 events/h) and moderate-to-severe OSA (REI ≥ 15 events/h).ResultsAmong 315 CDs recruited, 243 (77%) completed the study protocol, while 72 subjects were excluded for inadequate HSAT quality. The demographics and clinical data were comparable in both the included and excluded subjects. The included CDs had a median age of 50 years (interquartile range (IQR) 25–70) and a mean body mass index of 27 ± 4 kg/m2. One hundred and seventy-one subjects (71%) had OSA, and 68 (28%) had moderate-to-severe OSA. A receiver operating characteristic curve of the questionnaires were 0.51–0.71 for predicting OSA and 0.51–0.66 for moderate-to-severe OSA. The STOP-BANG questionnaire had an unsatisfactory positive predictive value, while all of the other questionnaires had an inadequate negative predictive value.ConclusionsStandard OSA questionnaires are not suited for screening among CDs. The use of the HSAT could provide an objective evaluation of for OSA in this special population.

Yu, Chung-Chieh; Huang, Chih-Yu; Hua, Chung-Ching; Wu, Huang-Pin

doi: 10.1007/s11325-021-02413-0pmid: 34145538

PurposeContinuous positive airway pressure (CPAP) is a standard treatment for obstructive sleep apnea (OSA). However, CPAP has limitations. High-flow nasal cannula (HFNC) is already in use for various types of respiratory diseases. As HFNC generates positive airway pressure, it may be a potential candidate for OSA treatment. This prospective study compared the therapeutic effects of HFNC to CPAP in patients with OSA.MethodsPatients whose apnea–hypopnea index (AHI) was > 5 events/h were enrolled in this study. All participants were randomly divided into two groups. The first group underwent CPAP the first night and HFNC the second night. Conversely, the second group received HFNC the first night and CPAP the second night. Their respiratory events and sleep quality were compared using baseline polysomnography, CPAP, and HFNC.ResultsIn total, 28 participants completed this study. Median [interquartile range] AHI (35.0 [20.0–48.6] vs. 10.8 [5.5–20.6] events/h; p < 0.001) was significantly improved by the HFNC. However, sleep quality was not improved. When CPAP was compared directly with HFNC, CPAP demonstrated a more favorable effect for respiratory events (AHI 5.0 [2.0–7.0] vs. 10.8 [5.5–20.6] events/h; p < 0.001) and sleep efficiency (88.1 [79.9–92.5] vs. 77.9 [69.2–86.6] %; p = 0.001).ConclusionThe efficacy of CPAP was superior to HFNC for both respiratory events and sleep quality.Trial registrationClinicalTrials.gov Identifier: NCT03843372; URL: www.clinicaltrials.gov; Date of registration: November 2, 2019

Chen, Meng-Xue; Chen, Li-Da; Zeng, Ai-Ming; Lin, Xue-Jun; Huang, Jian-Chai; Huang, Jie-Feng; Lai, Guo-Xiang; Lin, Qi-Chang

doi: 10.1007/s11325-021-02416-xpmid: 34148174

PurposePrior reports have examined the relationship between obstructive sleep apnea (OSA) and the mortality rate of lung cancer. However, the findings remain controversial. The present meta-analysis was performed to assess the relationship between OSA and increased risk of mortality in patients with lung cancer.MethodsPubMed, Web of Science, and Embase were systematically searched for the correlative studies. Data were analyzed and pooled to evaluate odds ratios (ORs) of lung cancer mortality related to OSA.ResultsFrom 249 identified studies, 3 met inclusion criteria and were analyzed, including 67 patients with lung cancer and comorbid OSA and 45 patients with lung cancer and no OSA. The meta-analysis indicated that OSA was not significantly correlated with mortality rate in lung cancer (OR = 2.005, 95% CI = 0.703 to 5.715, z = 1.30, p = 0.193). There was no significant publication bias according to Begg’s tests (p = 0.296) and Egger’s tests (p = 0.097).ConclusionThis meta-analysis suggests that OSA is not significantly correlated with the mortality rate in lung cancer.

Çakmakcı, Selin; Özgen Alpaydın, Aylin; Özalevli, Sevgi; Öztura, İbrahim; İtil, Bahriye Oya

doi: 10.1007/s11325-021-02423-ypmid: 34169482

PurposeObstructive sleep apnea (OSA) is an important public health problem. Beyond common treatment options, solution-oriented options are needed. Oropharyngeal exercise training may be a research area in this respect. This study aimed to evaluate the effects of oropharyngeal exercise (OPE) in addition to continuous positive airway pressure (CPAP) therapy in patients diagnosed with OSA.MethodsPatients with moderate and severe OSA were screened from the electronic database of our hospital and 41 patients (20: exercise group; 21: control group) were included in the study. Each patient was assessed with CPAP usage time, maximal voluntary ventilation (MVV), maximum inspiratory and expiratory pressure (MIP-MEP), neck circumference, body mass index (BMI), waist-hip ratio, Epworth sleepiness score, Pittsburgh sleep quality index (PSQI), and short-form health survey (SF-36) in the first visit. The OPE was prescribed in addition to CPAP for the exercise group and performed by the patients for 3 months. At the end of the third month, groups were re-assessed with the same parameters.ResultsMost of the patients were men, and the mean age of the study population was 51.9 ± 7.4; the mean apnea–hypopnea index (AHI) in the last polysomnography report was 53.3 ± 27.4. In the exercise group, MVV (p = 0.003), MIP (p = 0.002), MEP (p = 0.024), and SF-36 energy/fatigue (p = 0.020) were observed to increase while the total PSQI score (p = 0.036) decreased. The neck circumference (p = 0.006) and BMI (p = 0.013) were found to be significantly decreased in the exercise group.ConclusionsWe found that OPE training may have improved respiratory muscle strength as well as sleep quality and health-related quality of life in the exercise group. OPE along with CPAP therapy may be recommended in moderate and severe OSA patients who are willing to participate.

Olafsson, Thorarinn Arnar; Steinsvik, Eivind Andreas; Bachmann-Harildstad, Gregor; Hrubos-Strøm, Harald

doi: 10.1007/s11325-021-02374-4pmid: 34181175

Study objectivesThe aim of this study was to validate the automatically scored results of an esophageal probe–based polygraph system (ApneaGraph® Spiro) against manually scored polysomnography (Nox A1, PSG) results. We compared the apnea–hypopnea index, oxygen saturation index, and respiratory disturbance index of the devices.MethodsConsenting patients, referred for obstructive sleep apnea workup, were tested simultaneously with the ApneaGraph® Spiro and Nox A1® polysomnograph. Each participant made one set of simultaneous registrations for one night. PSG results were scored independently. Apnea–hypopnea index, oxygen desaturation index, and respiratory disturbance index were compared using Pearson’s correlation and scatter plots. Sensitivity, specificity, and positive likelihood ratio of all indices at 5, 15, and 30 were calculated.ResultsA total of 83 participants had successful registrations. The apnea–hypopnea index showed sensitivity of 0.83, specificity of 0.95, and a positive likelihood ratio of 5.11 at an index cutoff of 15. At a cutoff of 30, the positive likelihood ratio rose to 31.43. The respiratory disturbance index showed high sensitivity (> 0.9) at all cutoffs, but specificity was below 0.5 at all cutoffs. Scatterplots revealed overestimation in mild OSA and underestimation in severe OSA for all three indices.ConclusionsThe ApneaGraph® Spiro performed acceptably when OSA was defined by an AHI of 15. The equipment overestimated mild OSA and underestimated severe OSA, compared to the PSG.

Kim, Jung-Eun; Hwang, Kyoung-Jin; Kim, Sung-Wan; Liu, Stanley Yung-Chuan; Kim, Su-Jung

doi: 10.1007/s11325-021-02426-9pmid: 34181174

PurposeThe aim of this study was to investigate the correlation between the changes in respiratory function and dimensions of the nasomaxillary complex (NMC) and upper airway (UA) compartments after nasomaxillary skeletal expansion (NMSE) treatment for pediatric patients with obstructive sleep apnea (OSA).MethodsNonobese OSA patients (mean age, 13.6 ± 2.9 years; mean body mass index, 18.1 ± 3.0 kg/m2); mean apnea–hypopnea index (AHI, 7.0 ± 5.4 events/h) presenting with transverse nasomaxillary constriction were evaluated before and after NMSE using cone-beam computed tomography (CBCT), home sleep test, and modified pediatric sleep questionnaire (m-PSQ). Paired t tests were performed to examine the treatment-related changes in all the parameters, and a multiple regression analysis adjusted for age and sagittal and vertical skeletal patterns was conducted to determine the dimensional parameters to affect the functional improvement.ResultsAmong 26 patients, NMSE treatment significantly increased NMC dimensions at all tested levels and all UA compartments in CBCT, except glossopharyngeal airway. Concurrently, AHI, oxygen desaturation index, the lowest oxygen saturation (LSaO2), flow limitation (FL), snoring, and m-PSQ were significantly improved. AHI reduction was correlated with UA enlargement with no correlation with NMC expansion, whereas FL reduction was affected by NMC expansion. The minimal cross-sectional area was the most predictive of functional improvement, presenting correlations with AHI, LSaO2, and m-PSQ.ConclusionNMSE can be a good treatment for pediatric OSA patients when applied to enhance the nasal and pharyngeal airway patencies beyond the NMC, ultimately to improve pharyngeal collapsibility as well as nasal airflow.