Sleep-related Breathing Events Research Articles

Assessing the severity of sleep apnea syndrome based on ballistocardiogram.

BackgroundSleep Apnea Syndrome (SAS) is a common sleep-related breathing disorder, which affects about 4-7% males and 2-4% females all around the world. Different approaches have been adopted to diagnose SAS and measure its severity, including the gold standard Polysomnography (PSG) in sleep study field as well as several alternative techniques such as single-channel ECG, pulse oximeter and so on. However, many shortcomings still limit their generalization in home environment. In this study, we aim to propose an efficient approach to automatically assess the severity of sleep apnea syndrome based on the ballistocardiogram (BCG) signal, which is non-intrusive and suitable for in home environment.MethodsWe develop an unobtrusive sleep monitoring system to capture the BCG signals, based on which we put forward a three-stage sleep apnea syndrome severity assessment framework, i.e., data preprocessing, sleep-related breathing events (SBEs) detection, and sleep apnea syndrome severity evaluation. First, in the data preprocessing stage, to overcome the limits of BCG signals (e.g., low precision and reliability), we utilize wavelet decomposition to obtain the outline information of heartbeats, and apply a RR correction algorithm to handle missing or spurious RR intervals. Afterwards, in the event detection stage, we propose an automatic sleep-related breathing event detection algorithm named Physio_ICSS based on the iterative cumulative sums of squares (i.e., the ICSS algorithm), which is originally used to detect structural breakpoints in a time series. In particular, to efficiently detect sleep-related breathing events in the obtained time series of RR intervals, the proposed algorithm not only explores the practical factors of sleep-related breathing events (e.g., the limit of lasting duration and possible occurrence sleep stages) but also overcomes the event segmentation issue (e.g., equal-length segmentation method might divide one sleep-related breathing event into different fragments and lead to incorrect results) of existing approaches. Finally, by fusing features extracted from multiple domains, we can identify sleep-related breathing events and assess the severity level of sleep apnea syndrome effectively.ConclusionsExperimental results on 136 individuals of different sleep apnea syndrome severities validate the effectiveness of the proposed framework, with the accuracy of 94.12% (128/136).

Pilot Study Assessing the Impact of Intrathecal Baclofen Administration Mode on Sleep-Related Respiratory Parameters

Bensmail D, Marquer A, Roche N, Godard A-L, Lofaso F, Quera-Salva M-A. Pilot study assessing the impact of intrathecal baclofen administration mode on sleep-related respiratory parameters. Objective To assess the impact of intrathecal baclofen (ITB) mode of administration on sleep and sleep-related breathing events in severely disabled patients with severe spasticity. Design Open prospective trial. Setting Physical medicine and rehabilitation department. Participants Patients (N=11) treated with ITB pump for severe spasticity. Intervention Assessment of patients' sleep before and after ITB pump implantation, and comparison of polysomnography results after continuous or bolus mode of administration of ITB. Main Outcome Measures Polysomnography and sleep-related breathing events. Results ITB reduced periodic limb movements and increased the respiratory disturbance index (RDI) and central apneas in our population of patients. This study showed that ITB mode of administration may affect sleep-disordered breathing. Indeed, we observed a significant increase of respiratory events in the bolus condition (RDI and central apneas). In contrast, continuous infusion did not induce a significant modification of sleep-disordered breathing. When a sleep apnea syndrome was preexisting, it was generally severely worsened by the bolus mode of administration. Conclusions These results indicate that sleep function and sleep-related respiratory events should be assessed before ITB pump implantation. It is probably better to use a continuous mode of infusion if patients have preexisting sleep-disordered breathing.

Relationship between Metabolic Syndrome and Sleep-Disordered Breathing in Patients with Cardiovascular Disease -Metabolic Syndrome as a Strong Factor of Nocturnal Desaturation-

Metabolic syndrome (MetS) is one of the coronary risk factors for cardiovascular disease and is closely related with sleep-disordered breathing (SDB). Our aim in this study was to estimate the relationship between sleep-related breathing events and coronary risk factors, including MetS. We determined the prevalence of MetS in 195 patients with cardiovascular disease. Based on Japanese MetS criteria, 56 patients had MetS (Group A), whereas 139 patients did not (Group B). We assessed SDB and sleep-related breathing events, including nocturnal desaturation, in both groups using a type 3 apparatus (Morpheus); Teijin Pharma Limited, Tokyo, Japan). Seventy-seven percent of the patients with MetS (43/56) met the criteria for SDB based on apnea hypopnea index (AHI). The AHI value was significantly greater in Group A than in Group B (30.1 +/- 19.0/hr vs. 17.7 +/- 14.7/hr; p < 0.001). Nocturnal oximetry showed that Group A spent a greater percentage of time at pulse-oximetric oxygen saturation below 90% (CT 90) than did Group B (10.6 +/- 13.2% vs. 5.0 +/- 12.5%; p < 0.01). On multivariate logistic regression analysis for CT 90, MetS showed that the odds ratio was 2.629 (95% confidence interval: 1.259-5.592; p = 0.011). These results suggest that SDB is common in cardiovascular patients with MetS. Patients with MetS frequently experience a sleep-related breathing event. Compared with the incidence of apnea hypopnea, MetS is an equivalently strong factor of nocturnal desaturation in patients with cardiovascular disease.

Effect of atrial overdrive pacing on obstructive sleep apnea in patients with systolic heart failure

Background and purpose: Obstructive sleep apnea (OSA) is associated with cardiovascular disease. Preliminary studies suggested breathing improvement in patients with apnea and heart disease when atrial overdrive pacing was applied during sleep. However, more recent studies do not show significant beneficial effect for atrial overdrive pacing in OSA. To further investigate this relationship, we conducted a randomized clinical trial evaluating the effect of atrial overdrive pacing on sleep-related breathing events in subjects with OSA and systolic heart failure. Patients and methods: We screened 33 subjects with symptoms consistent with OSA. On a screening overnight polysomnography (PSG), 15 subjects with mean age of 74 years (standard deviation (SD) 6.6) and ejection fraction of 38% (SD 14.4%) had OSA defined as having an apnea/hypopnea index (AHI) of ⩾15 per hour of sleep. These subjects underwent additional PSGs including a night with atrial overdrive pacing (O), a night with pacemaker rate set at 40–50 beats per minutes (N), and a positive airway pressure titration night. The O and N nights were consecutive and the order was randomized. For O, the pacemaker rate was set at 15 beats higher than the average nightly heart rate (determined from the screening night). Results: At baseline, mean AHI was 34.8 (15.5) and mean SaO 2 nadir was 85% (3.2%). Average heart rate was significantly higher on O nights compared to N nights ( p < 0.005). The apnea index (AI) was statistically lower on O nights compared to N nights (18 ± 16.6 vs. 24 ± 18.9, p < 0.05). However, AHI and minimum and average O 2 saturations did not differ significantly between O and N nights. Interestingly, AHI improved statistically significantly on O nights in younger subjects. Conclusions: While statistically reliable, the small pacing-related reduction in sleep-disordered breathing (SDB) events is of unknown clinical significance. By contrast, continuous positive airway pressure (CPAP) dramatically improved AHI, AI, respiratory arousal index, and O 2 saturation. Thus our data suggest that overdrive pacing exerts a mild effect on respiratory events in some heart failure patients with OSA; however, atrial overdrive pacing was not therapeutically effective for improving airway patency and sleep-related respiratory function.