Changes In Obstructive Sleep Apnea Research Articles

Recent progresses in gut microbiome mediates obstructive sleep apnea-induced cardiovascular diseases.

Obstructive sleep apnea (OSA) is a multifactorial sleep disorder with a high prevalence in the general population. OSA is associated with an increased risk of developing cardiovascular diseases (CVDs), particularly hypertension, and is linked to worse outcomes. Although the correlation between OSA and CVDs is firmly established, the mechanisms are poorly understood. Continuous positive airway pressure is primary treatment for OSA reducing cardiovascular risk effectively, while is limited by inadequate compliance. Moreover, alternative treatments for cardiovascular complications in OSA are currently not available. Recently, there has been considerable attention on the significant correlation between gut microbiome and pathophysiological changes in OSA. Furthermore, gut microbiome has a significant impact on the cardiovascular complications that arise from OSA. Nevertheless, a detailed understanding of this association is lacking. This review examines recent advancements to clarify the link between the gut microbiome, OSA, and OSA-related CVDs, with a specific focus on hypertension, and also explores potential health advantages of adjuvant therapy that targets the gut microbiome in OSA.

Systematic review of miRNA expression changes in Obstructive Sleep Apnea: insights into associated pathways and contribution to disease

Systematic review of miRNA expression changes in Obstructive Sleep Apnea: insights into associated pathways and contribution to disease

Acute Effect of Positive Airway Pressure on Heart Rate Variability in Obstructive Sleep Apnea.

Autonomic dysregulation is associated with cardiovascular consequences in obstructive sleep apnea (OSA). This study aimed to investigate the effect of acute continuous positive airway pressure (CPAP) treatment on autonomic activity and to identify factors contributing to heart rate variability (HRV) changes in OSA. Frequency domain HRV parameters were calculated and compared between the baseline polysomnography and during the CPAP titration in 402 patients with moderate to severe OSA. There were significant reductions in total power, very low-frequency band power, low-frequency band power, and high-frequency band power during the CPAP titration as compared to the baseline polysomnography. This tendency was pronounced in male patients with severe OSA. Multivariate analysis found that changes in the apnea-hypopnea index and oxygen saturation were significantly associated with changes in sympathetic and parasympathetic activity, respectively. This study demonstrated that HRV parameters significantly changed during the CPAP titration, indicating a beneficial effect of CPAP in the restoration of sympathetic and parasympathetic hyperactivity in OSA. Prospective longitudinal studies should determine whether long-term CPAP treatment aids in maintaining the long-lasting improvement of the autonomic functions, thereby contributing to the prevention of cardiovascular and cerebrovascular diseases in patients with OSA.

Retrospective Analysis of the Polysomnographic and Airway Changes in Obstructive Sleep Apnea (OSA) Subjects Who Underwent Maxillomandibular Advancement (MMA) Surgery

Retrospective Analysis of the Polysomnographic and Airway Changes in Obstructive Sleep Apnea (OSA) Subjects Who Underwent Maxillomandibular Advancement (MMA) Surgery

Developmental changes in obstructive sleep apnea and sleep architecture in Down syndrome.

Down syndrome (DS, also known as Trisomy 21) is a condition associated with abnormal neurodevelopment and a higher risk for sleep apnea. Our study sought to better understand and characterize the age-related developmental differences in sleep architecture and obstructive sleep apnea (OSA) severity in children with DS compared to euploid individuals. Retrospective review of polysomnograms in over 4151 infants, children, and adolescents in the pediatric sleep center at Children's National Hospital in Washington D.C. (0-18 years) including 218 individuals with DS. The primary findings of our study are that: (1) severe OSA (obstructive apnea-hypopnea index ≥ 10/h) was more prevalent in the DS group (euploid 18% vs. DS 34%, p < 0.001) with the highest OSA severity being present in young children (<3 years old) and adolescents (>10 years old), (2) abnormalities in sleep architecture in children with DS were characterized by a prolonged rapid-eye movement (REM) sleep onset latency (SOL) (euploid 119 min vs. DS 144 min, p < 0.001) and greater arousal indexes (euploid 10.7/h vs. DS 12.2/h, p < 0.001), (3) developmental changes in the amount of REM sleep or slow wave sleep were not different in DS individuals relative to euploid children, (4) multivariate analyses showed that OSA and REM sleep latency differences between DS and euploid individuals were still present after adjusting by age, biological sex, and body mass index. Severe OSA is highly prevalent in children with DS and follows an age-dependent "U" distribution with peaks in newborns/infants and children >10 years of age. Children with DS also have disturbances in sleep architecture characterized by a longer REM SOL and elevated arousal indexes. As sleep cycle generation and continuity play crucial roles in neuroplasticity and cognitive development, these findings offer clinically relevant insights to guide anticipatory guidance for infants, children, and adolescents with DS.

The complex interplay of hypoxia and sleep disturbance in gray matter structure alterations in obstructive sleep apnea patients.

Obstructive Sleep Apnea (OSA) characteristically leads to nocturnal hypoxia and sleep disturbance. Despite clear evidence of OSA-induced cognitive impairments, the literature offers no consensus on the relationship between these pathophysiological processes and brain structure alterations in patients. This study leverages the robust technique of structural equation modeling to investigate how hypoxia and sleep disturbance exert differential effects on gray matter structures. Seventy-four Male participants were recruited to undergo overnight polysomnography and T1-weighted Magnetic Resonance Imaging. Four structural outcome parameters were extracted, namely, gray matter volume, cortical thickness, sulcal depth, and fractal dimension. Structural equation models were constructed with two latent variables (hypoxia, and sleep disturbance) and three covariates (age, body mass index, and education) to examine the association between gray matter structural changes in OSA and the two latent variables, hypoxia and sleep disturbance. The structural equation models revealed hypoxia-associated changes in diverse regions, most significantly in increased gray matter volume, cortical thickness and sulcal depth. In contrast, sleep disturbance. Was shown to be largely associated with reduce gray matter volume and sulcal depth. This study provides new evidence showing significant effects of OSA-induced hypoxia and sleep disturbance on gray matter volume and morphology in male patients with obstructive sleep apnea. It also demonstrates the utility of robust structural equation models in examining obstructive sleep apnea pathophysiology.

The Impact of Mouth-Taping in Mouth-Breathers with Mild Obstructive Sleep Apnea: A Preliminary Study.

Background: Many patients with obstructive sleep apnea (OSA) are mouth-breathers. Mouth-breathing not only narrows the upper airway, consequently worsening the severity of OSA, but also it affects compliance with nasal continuous positive airway pressure (CPAP) treatment. This study aimed to investigate changes in OSA by the use of mouth tape in mouth-breathers with mild OSA. Method: Mouth-breathers with mild OSA who met inclusion criteria and tolerated the sealing of the mouth were enrolled in the study. We used 3M silicone hypoallergenic tape was used to seal the mouths of the participants during sleep. The home sleep test (HST) used in this study was ApneaLink®. Subjects received both a baseline HST and an outcome HST to be used 1 week later while their mouths were taped. The changes between the baseline and the outcome HSTs were compared, and the factors that influenced the differences in the sleep-test parameters after the shift of the breathing route were analyzed. A “responder” was defined as a patient who experienced a reduction from the baseline snoring index of at least 50% under mouth-taping in the HST; otherwise, patients were considered as having a poor response. Results: A total of 20 patients with mild OSA were included. Following the taping of the mouth, a good response was found in 13 patients (65%). The median apnea/hypopnea index (AHI) decreased significantly, from 8.3 to 4.7 event/h (by 47%, p = 0.0002), especially in supine AHI (9.4 vs. 5.5 event/h, p = 0.0001). The median snoring index (SI) was also improved (by 47%, 303.8 vs. 121.1 event/h, p = 0.0002). Despite no significant difference in the mean saturation, improvements in the oxygen desaturation index (8.7 vs. 5.8, p = 0.0003) and the lowest saturation (82.5% vs. 87%, p = 0.049) were noted. The change in AHI was associated with baseline AHI (r = −0.52, p = 0.02), oxygen desaturation index (ODI) (r = −0.54, p = 0.01), and SI (r = −0.47, p = 0.04). The change in SI was strongly associated with baseline SI (r = −0.77, p = 0.001). Conclusions: Mouth-taping during sleep improved snoring and the severity of sleep apnea in mouth-breathers with mild OSA, with AHI and SI being reduced by about half. The higher the level of baseline AHI and SI, the greater the improvement was shown after mouth-taping. Mouth-taping could be an alternative treatment in patients with mild OSA before turning to CPAP therapy or surgical intervention.

The Role of Inflammation, Hypoxia, and Opioid Receptor Expression in Pain Modulation in Patients Suffering from Obstructive Sleep Apnea.

Obstructive sleep apnea (OSA) is a relatively common disease in the general population. Besides its interaction with many comorbidities, it can also interact with potentially painful conditions and modulate its course. The association between OSA and pain modulation has recently been a topic of concern for many scientists. The mechanism underlying OSA-related pain connection has been linked with different pathophysiological changes in OSA and various pain mechanisms. Furthermore, it may cause both chronic and acute pain aggravation as well as potentially influencing the antinociceptive mechanism. Characteristic changes in OSA such as nocturnal hypoxemia, sleep fragmentation, and systemic inflammation are considered to have a curtailing impact on pain perception. Hypoxemia in OSA has been proven to have a significant impact on increased expression of proinflammatory cytokines influencing the hyperalgesic priming of nociceptors. Moreover, hypoxia markers by themselves are hypothesized to modulate intracellular signal transduction in neurons and have an impact on nociceptive sensitization. Pain management in patients with OSA may create problems arousing from alterations in neuropeptide systems and overexpression of opioid receptors in hypoxia conditions, leading to intensification of side effects, e.g., respiratory depression and increased opioid sensitivity for analgesic effects. In this paper, we summarize the current knowledge regarding pain and pain treatment in OSA with a focus on molecular mechanisms leading to nociceptive modulation.

Relationships between brain tissue damage, oxygen desaturation, and disease severity in obstructive sleep apnea evaluated by diffusion tensor imaging.

Patients with obstructive sleep apnea (OSA) show brain injury in sites responsible for autonomic, cognitive, and respiratory functions. Brain changes in OSA may vary with disease severity as assessed by the apnea-hypopnea index (AHI), which does not provide information about the apnea depth and length in contrast to oxygen desaturation. Although significant associations with brain injury and AHI are known in OSA, it is unclear whether AHI or the extent of oxygen desaturations better correlate with brain damage. We evaluated associations between brain changes, AHI, and oxygen desaturation using diffusion tensor imaging-based measures. We acquired diffusion tensor imaging data from 19 patients with OSA using a 3.0-Tesla MRI scanner and calculated, normalized, and smoothed mean, axial, and radial diffusivity maps that were used for correlations between brain changes, oxygen desaturation, and AHI values. Positive correlations with extent of injury (mean, axial, and radial diffusivity values) and AHI appeared in the frontal areas, cingulate and insula, amygdala, hippocampus, and basal pons, and negative associations emerged in the putamen, internal-capsule, globus-pallidus, and cerebellar cortices. Regional diffusivity values and oxygen desaturation showed positive correlations in the cingulate, frontal, putamen, and cerebellar sites, and negative relationships in several areas, including the occipital cortex. Patients with OSA show negative and positive correlations, indicated by increased and decreased diffusivity values, resulting from chronic and acute changes in those areas. The extent of injury in OSA partially depends on the extent of AHI and oxygen desaturation, with the effects representing continued development from acute to chronic processes. Sahib A, Roy B, Kang D, Aysola RS, Wen E, Kumar R. Relationships between brain tissue damage, oxygen desaturation, and disease severity in obstructive sleep apnea evaluated by diffusion tensor imaging. J Clin Sleep Med. 2022;18(12):2713-2721.

The association between obstructive sleep apnea and sleep spindles in middle-aged and older men: a community-based cohort study.

Sleep spindles show morphological changes in obstructive sleep apnea (OSA). However, previous small studies have limited generalizability, leaving associations between OSA severity measures and spindle metrics uncertain. This study examined cross-sectional associations between OSA severity measures and spindle metrics among a large population-based sample of men. Community-dwelling men with no previous OSA diagnosis underwent home-based polysomnography. All-night EEG (F4-M1) recordings were processed for artifacts and spindle events identified using previously validated algorithms. Spindle metrics of interest included frequency (Hz), amplitude (µV2), overall density (11-16 Hz), slow density (11-13 Hz), and fast density (13-16 Hz) (number/minute). Multivariable linear regression models controlling for demographic, biomedical, and behavioral confounders were used to examine cross-sectional associations between OSA severity measures and spindle metrics. In adjusted analyses, higher apnea-hypopnea index (AHI/h, as a continuous variable) and percentage total sleep time with oxygen saturation <90% (TST90) were associated with decreased slow spindle density (AHI, B = -0.003, p = 0.032; TST90, B = -0.004, p = 0.047) but increased frequency (AHI, B = 0.002, p = 0.009; TST90, B = 0.002, p = 0.043). Higher TST90 was also associated with greater spindle amplitude (N2 sleep, B = 0.04, p = 0.011; N3 sleep, B = 0.11, p < 0.001). Furthermore, higher arousal index was associated with greater spindle amplitude during N2 sleep (B = 0.31, p < 0.001) but decreased overall density (B = -1.27, p = 0.030) and fast density (B = -4.36, p = 0.028) during N3 sleep. Among this large population-based sample of men, OSA severity measures were independently associated with spindle abnormalities. Further population studies are needed to determine associations between spindle metrics and functional outcomes.

The positional characteristics of patients with obstructive sleep apnea: a single institute retrospective study in Japan.

Obstructive sleep apnea (OSA) causes sleep-disordered breathing (SDB) due to upper airway obstruction. The severity of OSA changes with position during sleep. Patients with marked significant improvement in apnea-hypopnea index (AHI) level by sleep position change are defined as ''positional patients'' (PP), while those without improvement are defined as ''non-positional patients'' (NPP). We aimed to verify their clinical characteristics. Between May 2008 and May 2020, 237 patients with OSA were registered retrospectively and classified into two groups: PP (n = 158) and NPP (n = 79). The differences in clinical background and full-night polysomnography (PSG) between the two groups were observed. A logistic regression analysis was conducted to identify the risk factors for severe AHI (≥ 30 events/h) in the PP group. Moreover, confounding factor-adjusted sub-analysis by a propensity score matching method was performed, and the PSG results were compared between the two groups. The PP group was older than the NPP group. Furthermore, the PP group had lower body mass index (BMI) and AHI levels compared with the NPP group. The independent risk factors for severe AHI in the PP group were BMI and being in the supine position during sleep. The PP group had a significantly milder nocturnal hypoxemia despite having no significant difference in AHI levels between the two groups. The characteristics of PP were old age, low BMI, and low AHI associated with milder nocturnal hypoxemia. Moreover, they were less likely to worsen with nocturnal hypoxemia compared with NPP having similar severity.

Impact of bariatric surgery on obstructive sleep apnea severity and continuous positive airway pressure therapy compliance\u2014prospective observational study

To evaluate association between bariatric surgery and changes in obstructive sleep apnea (OSA) severity and sleep architecture was as well as to asses continuous positive airway pressure (CPAP) effectiveness and compliance. We enrolled patients undergoing bariatric surgery. Polysomnography was performed in each patient preoperatively and 12 months after the procedure in a subgroup of patients diagnosed with OSA. STOP-BANG, Epworth Sleepiness Scale (ESS) and Berlin questionnaire scores were obtained pre- and postoperatively. CPAP compliance data was recorded during follow-up hospitalization. Among 44 patients with median age of 49.5 years, predominantly women (68.2%) pre- and postoperative polysomnography was performed. We observed significant improvement in STOP-BANG (6.0 vs. 3.0, p < 0.001) and ESS (12.0 vs. 5.0, p < 0.001) scores, apnea–hypopnea index (44.9 vs. 29.2, p < 0.001), oxygen desaturation index (43.6 vs. 18.3, p < 0.001) and sleep architecture parameters. CPAP compliance was poor with a median percentage of days with CPAP use accounting to 49.3%. Bariatric surgery is associated with a significant decrease in the number of sleep-related respiratory disturbances, as well as improvement of sleep efficiency. Postoperative CPAP therapy compliance was poor despite low rate of OSA resolution. This study suggests that patients with OSA undergoing bariatric surgery require postoperative reassessment.

The impact of continuous positive airway pressure treatment on retinal vascular changes in obstructive sleep apnea

Obstructive sleep apnea (OSA) was recently shown to be associated with quantifiable retinal vascular changes, which correlate with disease severity. This follow-up study examines the response of retinal vascular changes in patients with OSA receiving continuous positive airway pressure (CPAP) treatment. This prospective cohort study recruited adult patients undergoing diagnostic polysomnography at a tertiary sleep clinic in Sydney, Australia, stratified into 4 groups by the apnea-hypopnea index; control patients and patients with mild, moderate, and severe OSA. At baseline and follow-up approximately 24 months later, static retinal vascular calibers were derived from fundus photographs, and dynamic vascular pulsation amplitudes were measured on video fundoscopy. A proportion of patients started CPAP therapy after baseline assessment. Seventy-nine patients participated in this follow-up study: 9 control patients and 18 patients with mild OSA, 21 patients with moderate OSA, and 31 patients with severe OSA. Twenty-five patients started CPAP after baseline. In the severe group, patients not on treatment showed progressive narrowing of retinal arteries from baseline, whereas those on CPAP showed a slight improvement (mean, 171.3-165.1 and 171.2-174.0 μm, respectively; P = .012). Arterio-venous ratio was also significantly reduced in the nontreatment group compared to the treatment group in those with severe OSA (0.836-0.821 and 0.837-0.855, respectively; P = .031). CPAP did not seem to have a significant impact on venous caliber or vascular pulsatility. This study shows that patients with severe untreated OSA demonstrate progressive retinal arterial narrowing, whereas CPAP treatment may be protective.

Does craniofacial morphology relate to sleep apnea severity reduction following weight loss intervention? A patient-level meta-analysis.

Obesity is a common and reversible risk factor for obstructive sleep apnea (OSA). However, there is substantial unexplained variability in the amount of OSA improvement for any given amount of weight loss. Facial photography is a simple, inexpensive, and radiation-free method for craniofacial assessment. Our aims were (1) to determine whether facial measurements can explain OSA changes, beyond weight loss magnitude and (2) whether facial morphology relates to how effective weight loss will be for OSA improvement. We combined data from three weight loss intervention trials in which participants had standardized pre-intervention facial photography (N = 91; 70.3% male, mean ± SD weight loss 10.4 ± 9.6% with 20.5 ± 51.2% apnea-hypopnea index [AHI] reduction). Three skeletal-type craniofacial measurements (mandibular length, lower face height, and maxilla-mandible relationship angle) were assessed for relationship to AHI change following weight loss intervention. Weight and AHI changes were moderately correlated (rho = 0.3, p = 0.002). In linear regression, an increased maxilla-mandible relationship angle related to AHI improvement (β [95% CI] -1.7 [-2.9, -0.5], p = 0.004). Maxilla-mandible relationship angle explained 10% in the variance in AHI over the amount predicted by weight loss amount (20%). The relationship between weight change and AHI was unaffected by the maxilla-mandible relationship angle (interaction term p > 0.05). Regardless of facial morphology, weight loss is similarly moderately predictive of OSA improvement. Increased maxilla-mandible relationship angle, suggestive of retrognathia, was weakly predictive of OSA response to weight loss. Although this is unlikely to be clinically useful, exploration in other ethnic groups may be warranted.

Obstructive sleep apnea and fatigue in patients with inflammatory arthritis taking TNF-inhibitors

p>Background: Fatigue is common in inflammatory arthritis (IA). Obstructive sleep apnea (OSA) causes fatigue and is common in IA. OSA and IA are associated with systemic inflammation, including elevated levels of tumor necrosis factor alpha (TNFα). Tumor necrosis factor inhibitors (TNFi) reduce musculoskeletal symptoms and fatigue in IA. The effects of TNFi on OSA are unknown. Our goal was to explore the relationships between TNFi, fatigue, and OSA in IA. Methods: Consecutive patients starting TNFi for IA and high risk for OSA were enrolled. OSA was assessed with the Apnea Hypopnea Index (AHI) and percent time below 90% oxygen saturation (%time < 90%). Fatigue was assessed with the Functional Severity Scale (FSS). Sleep was assessed with the Functional Outcome of Sleep Questionnaire (FOSQ). IA was assessed with the patient global assessment of arthritis (PGA). Parameters were compared before and after TNFi. Changes in OSA, sleep, and fatigue outcomes were adjusted for changes in the PGA. Findings: Eighteen participants completed the study between September 2011 and February of 2014. The mean age was 54 years. 72% were male. Before and after TNFi: mean AHIs were 12.5 and 13.1, respectively (p=0.97); mean %times < 90% were 29.5 and 35.4, respectively (p=0.18); and mean FSS scores were 43.1 and 41.3, respectively (p=0.08); mean FOSQ scores were 11.4 and 11.8, respectively (p=0.09). Conclusions: OSA parameters did not improve with TNFi, but there were statistically non-significant trends toward improvement in fatigue and sleepiness with TNFi.

Forkhead Box P3 Methylation and Expression in Men with Obstructive Sleep Apnea.

Background: Epigenetic changes in obstructive sleep apnea (OSA) have been proposed as a mechanism for end-organ vulnerability. In children with OSA, Forkhead Box P3 (FOXP3) DNA methylation were associated with inflammatory biomarkers; however, the methylation pattern and its effect in the expression of this gene have not been tested in adults with OSA. Methods: Plasma samples from subjects without comorbid conditions other than OSA were analyzed (the Epigenetics Status and Subclinical Atherosclerosis in Obstructive Sleep Apnea (EPIOSA) Study: NCT02131610). In 16 patients with severe OSA (Apnea-Hypopnea Index—AHI- > 30 events/h) and seven matched controls (AHI < 5), methylation of FOXP3 gen was evaluated by PCR of the promoter and by pyrosequencing of the intron 1 Treg-specific demethylated region (TSDR). In another 74 patients with OSA (AHI > 10) and 31 controls, we quantified FOXP3 protein expression by ELISA and gene expression by quantitative real-time PCR. C-reactive protein (CRP) and plasma Treg cells were also evaluated. Results: Neither the levels of the promoter nor the TSDR demethylated region were different between controls and patients with OSA, whether they were grouped by normal or high CRP. FOXP3 protein and mRNA expression did not differ between groups. Conclusions: FOXP3 methylation or its expression is not altered in adults with OSA, whatever their inflammatory status.

Effects on obstructive sleep apnea severity following a tailored behavioral sleep medicine intervention aimed at increased physical activity and sound eating: an 18-month follow-up of a randomized controlled trial.

Positive effects have been reported following a behavioral sleep medicine (BSM) intervention targeting physical activity and eating behavior in addition to continuous positive airway pressure (CPAP) treatment in patients with obstructive sleep apnea (OSA). Long-term follow-up remains to be explored. The aim was to examine the long-term effects of a tailored BSM intervention addressing physical activity and eating behavior in addition to CPAP treatment in patients with moderate to severe OSA combined with overweight and physical inactivity. Further, the aim was to identify variables at baseline, associated with treatment success regarding OSA severity. Sixty participants (body mass index: 34.5 ± 5.0 kg/m²; apnea-hypopnea index [AHI]: 43.7 ± 21.2 events/h) completed the randomized controlled trial with a follow-up at 18 months. The participants were randomized to either a control group treated with CPAP or an experimental group treated with CPAP and a BSM intervention targeting physical activity and eating behavior changes. OSA was categorized as mild (AHI: 5 to <14.9 events/h), moderate (AHI: 15 to <29.9 events/h), or severe (AHI ≥30 events/h). Being in the experimental group was associated with a larger improvement (B = -9.353, P = .029) in AHI at the 18-month follow-up compared with being in the control group when adjusting for baseline AHI and body mass index. Improvement in OSA category occurred more frequently in the experimental group participants (n = 11; 36.7%) compared with the control group (n = 2; 6.7%). Deterioration in OSA category was found in 1 (3.3%) participant in the experimental group and 3 (10%) in the control group. The importance of a BSM intervention as an adjunct treatment in patients with OSA is emphasized due to its long-term benefits. Registry: ClinicalTrials.gov; Name: Lifestyle changes in obstructive sleep apnea; Identifier: NCT01102920.

Aging effect on sleepiness and apneas severity in patients with obstructive sleep apnea syndrome: a meta-analysis study.

Different authors have reported that aging could be associated with changes in obstructive sleep apnea (OSA) related parameters (apnea/hypopnea index, SpO2, reduction of daytime sleepiness, etc.), type of sleep and pattern of collapse. Regarding OSA severity in elderly patients, it is commonly believed that the AHI score tends to increase with aging. In this paper, we reviewed the literature regarding the studies which compared older (>65years old) and young (<65years old) OSA patients regarding the effect of aging on daytime sleepiness (ESS evaluation) and OSA severity (AHI evaluation). A meta-analysis to evaluate the effect of age on daytime sleepiness and OSAS severity was also performed to corroborate previously reported experience. Meta-analysis showed no statistical (p = 0.8) differences regarding AHI differences emerged from the comparison of the two groups of patients. Elderly patients (>65years old) showed less daytime sleepiness, showing a statistical difference in the meta-analysis of data (p = 0.004) CONCLUSION: Although a direct correlation between aging and AHI values would seem to be present, no significant differences in baseline AHI between young (<65-years-old) and elderly (>65-years-old) patients emerged in this meta-analysis study. The effects of OSAS on daytime sleepiness seem to be much more prominent in young or middle-aged patients than in elderly patients.

Impact of Personal Health Records and Wearables on Health Outcomes and Patient Response: Three-Arm Randomized Controlled Trial.

BackgroundAlthough using the technologies for a variety of chronic health conditions such as personal health record (PHR) is reported to be acceptable and useful, there is a lack of evidence on the associations between the use of the technologies and the change of health outcome and patients’ response to a digital health app.ObjectiveThis study aimed to examine the impact of the use of PHR and wearables on health outcome improvement and sustained use of the health app that can be associated with patient engagement.MethodsWe developed an Android-based mobile phone app and used a wristband-type activity tracker (Samsung Charm) to collect data on health-related daily activities from individual patients. Dietary record, daily step counts, sleep log, subjective stress amount, blood pressure, and weight values were recorded. We conducted a prospective randomized clinical trial across 4 weeks on those diagnosed with obstructive sleep apnea (OSA) who had visited the outpatient clinic of Seoul National University Bundang Hospital. The trial randomly assigned 60 patients to 3 subgroups including 2 intervention groups: (1) mobile app and wearable device users (n=20), (2) mobile app–only users (n=20), and (3) controls (n=20). The primary outcome measure was weight change. Body weights before and after the trial were recorded and analyzed during clinic visits. Changes in OSA–related respiratory parameters such as respiratory disturbance, apnea-hypopnea, and oxygenation desaturation indexes and snoring comprised the secondary outcome and were analyzed for each participant.ResultsWe collected the individual data for each group during the trial, specifically anthropometric measurement and laboratory test results for health outcomes, and the app usage logs for patient response were collected and analyzed. The body weight showed a significant reduction in the 2 intervention groups after intervention, and the mobile app–only group showed more weight loss compared with the controls (P=.01). There were no significant changes in sleep-related health outcomes. From a patient response point of view, the average daily step counts (8165 steps) from the app plus wearable group were significantly higher than those (6034 steps) from the app-only group because they collected step count data from different devices (P=.02). The average rate of data collection was not different in physical activity (P=.99), food intake (P=.98), sleep (P=.95), stress (P=.70), and weight (P=.90) in the app plus wearable and app-only groups, respectively.ConclusionsWe tried to integrate PHR data that allow clinicians and patients to share lifelog data with the clinical workflow to support lifestyle interventions. Our results suggest that a PHR–based intervention may be successful in losing body weight and improvement in lifestyle behavior.Trial RegistrationClinicalTrials.gov NCT03200223; https://clinicaltrials.gov/ct2/show/NCT03200223 (Archived by WebCite at http://www.webcitation.org/74baZmnCX).

Feature relevance in physiological networks for classification of obstructive sleep apnea

Objective: Physiological networks (PN) model couplings between organs in a high-dimensional parameter space. Machine learning methods, in particular artifical neural networks (ANNs), are powerful on high-dimensional classification tasks. However, lack of interpretability of the resulting models has been a drawback in research. We assess relevant PN topology changes in obstructive sleep apnea (OSA) by novel ANN interpretation techniques. Approach: ANNs are trained to classify OSA based on the PNs of 48 patients and 48 age and gender matched healthy controls. The PNs consisting of 2812 links are derived from overnight biosignal recordings. The interpretation technique DeepLift is applied to the resulting ANN models, enabling the determination of the relevant features for classification decisions on individual subjects. The mean relevance scores of the features are compared to other machine learning methods (decision tree and random forests) and statistical tests on group differences. Main results: The ANN interpretation results show good agreement with the compared methods and 87% of the samples could be correctly classified. OSA patients show a significantly higher coupling (p 0.001) in light sleep (N2) between breathing rate and EEG power in all electrode locations and to chin and leg muscular tone. In deep sleep (N3), OSA leads to significantly lower coupling (p 0.01) in lateral connections of EEG and power in central and frontal positions. Misclassified OSA patients had all mild/moderate AHIs and did not show PN topology changes. Both nights of these patients have been consistently misclassified as healthy. This may indicate, that the impact of respiratory events differs in subjects, thus forming different phenotypes. Significance: The proposed PN analysis provides a powerful and robust method to quantify a broad range of physiological interactions. Interpretability of the ANN make them a promising tool to identify new diagnostic markers in data-driven approaches.