Months Of Continuous Positive Airway Pressure Research Articles

Continuous positive airway pressure compliance in patients with mild cognitive impairment.

Sleep apnoea (SA) is associated with accelerated cognitive decline in patients with mild cognitive impairment (MCI). Treatment of SA by continuous positive airway pressure (CPAP) may slow this decline if patients comply with the treatment. The aim of this study was to assess the rate of CPAP compliance in this population. In this single-centre retrospective study conducted in a tertiary care institution, patients with a diagnosis of MCI and SA initiating CPAP between January 2015 and August 2021 were included. Data from the initial sleep recording, the 3-month follow-up and compliance with at least 12months of CPAP were analysed. Compliance was defined as an average CPAP use of at least 4h per night. 55 patients were included (49% women, age 70.7 ± 8.9years, body mass index 28.9 ± 6.5kg/m2). Aetiology of MCI was vascular (45.5%), psychiatric (12.7%) and related to Alzheimer's disease (7.3%), with 47.3% of amnesic disorders and 45.5% of dysexecutive disorders. The MiniMentalState score was 26.7 ± 3.1. SA was mostly obstructive (81.8%) with a mean apnoea-hypopnoea index of 41.1 ± 16.4/h. At 3months, 38 patients were compliant (69%) with a CPAP median use of 5.9h per night and 83% of nights. Self-reported tolerance was better in compliant patients (75.7% vs 38.5% p = 0.017). Thirty-four patients remained compliant at 12months (62%). Our results suggest a high rate of CPAP compliance in patients suffering from MCI. Compliance was related to the device tolerance, emphasizing the need to closely monitor and improve this factor.

Abstract 18481: Paroxysmal Atrial Fibrillation and Sleep Apnea: Diurnal Patterning of Autonomic Function and Influence of CPAP Therapy

Introduction: Autonomic nervous system (ANS) dysfunction is implicated in sleep-disordered breathing (SDB) and atrial fibrillation (AF). Hypothesis: We hypothesize that ANS measures of heart rate variability (HRV) exhibit diurnal differences in paroxysmal AF(PAF) relative to SDB severity and is impacted by continuous positive airway pressure (CPAP). Methods: Data from the Sleep Apnea and Atrial Fibrillation Biomarkers and Electrophysiologic Atrial Triggers (SAFEBEAT) study including PAF (7-24 day ECG monitoring), concomitant actigraphy and SDB from polysomnography at baseline and 3-months post-CPAP were analyzed. Linear mixed-effects models were used to assess SDB (apnea hypopnea index (AHI), hypoxia (%sleep time with SaO2<90% and nadir SaO2) and diurnal average HRV (frequency domain (sympathovagal)): low-frequency range (LF), high-frequency range (HF), LF/HF; time domain: mean of normal RR interval (MNN), standard deviation of NN intervals (SDNN), SD1(Poincare plot standard deviation) and effect of 3-month CPAP. Results: In 44869 five-minute epochs from 109 participants with SDB and PAF, during wakefulness, associations of AHI and LFP, nadir SaO2 with sympathovagal measures (LFP, LHR) and time domain measures (SDNN, SD2) were observed. A sleep-wake significant interaction was observed with all HRV measures and stronger associations in wake than sleep. Baseline to follow-up CPAP time domain measures were increased during wakefulness (MNN, SDNN, RMSSD, CV, SD1, and SD2) and increased during sleep (MNN, SD2, LHR). Conclusions: Diurnal variation of autonomic measures in moderate to severe SDB was observed and association with SDB severity was more pronounced during wakefulness; CPAP influenced autonomic function. These findings in earlier onset AF may contribute to electrophysiological remodeling with implications for ANS-specific chronobiology in SDB.

Region-specific changes in brain activity and memory after continuous positive airway pressure therapy in obstructive sleep apnea: a pilot high-density electroencephalography study.

Limited channel electroencephalography (EEG) investigations in obstructive sleep apnea (OSA) have revealed deficits in slow wave activity (SWA) and spindles during sleep and increased EEG slowing during resting wakefulness. High-density EEG (Hd-EEG) has also detected local parietal deficits in SWA (delta power) during NREM. It is unclear whether effective continuous positive airway pressure (CPAP) treatment reverses regional SWA deficits, and other regional sleep and wake EEG abnormalities, and whether any recovery relates to improved overnight memory consolidation. A clinical sample of men with moderate-severe OSA underwent sleep and resting wake recordings with 256-channel Hd-EEG before and after 3 months of CPAP. Declarative and procedural memory tasks were administered pre- and post-sleep. Topographical spectral power maps and differences between baseline and treatment were compared using t-tests and statistical nonparametric mapping (SnPM). In 11 compliant CPAP users (5.2 ± 1.1 hours/night), total sleep time did not differ after CPAP but N1 and N2 sleep were lower and N3 was higher. Centro-parietal gamma power during N3 increased and fronto-central slow spindle activity during N2 decreased (SnPM < 0.05). No other significant differences in EEG power were observed. When averaged specifically within the parietal region, N3 delta power increased after CPAP (p = 0.0029) and was correlated with the change in overnight procedural memory consolidation (rho = 0.79, p = 0.03). During resting wakefulness, there were trends for reduced delta and theta power. Effective CPAP treatment of OSA may correct regional EEG abnormalities, and regional recovery of SWA may relate to procedural memory improvements in the short term.

Long-term outcomes of CPAP-treated sleep apnea patients: Impact of blood-pressure responses after CPAP initiation and of treatment adherence

Background and objectiveIn randomized controlled trials, continuous positive airway pressure (CPAP) is reported as lowering blood pressure (BP) with a mean systolic blood pressure effect size of 2.5 mmHg. These trials have a median follow-up of less than 6 months. Whether this initial BP response during the first months of CPAP treatment translates into a reduction in long-term cardiovascular events and mortality is unknown. MethodsThis observational study addressed long-term hard cardiovascular outcomes and all-cause mortality in a well-defined population of 241 patients previously included in the AgirSASadom parallel randomized controlled trial (assessing whether fixed-pressure CPAP was superior to auto-adjusted CPAP in reducing BP (baseline evaluations 2010–2012)). Long-term outcomes were analyzed using a Cox survival model, and a logistic regression analysis was performed for long-term CPAP adherence. ResultsSixty-nine cardiovascular events occurred in 61 patients during a median follow-up of 113 months (interquartile range [102 ; 124]) giving an incidence of 26 for 1000 person-years. Twenty-one (8.7%) patients died. BP values at baseline (i.e., office and 24-h BP) was a strong predictor of incident cardiometabolic events and mortality (p < 0.01) whereas initial BP response after the first four months of CPAP was not related to outcomes. Long-term CPAP adherence above 4 h/night was associated with a reduction in all-cause mortality (Log-rank P = 0.02) but not in the occurrence of long-term cardiovascular events. ConclusionIndependently of initial blood pressure response, long-term CPAP adherence is one of the prerequisites for reducing mortality.

Effect of positive airway pressure compliance on laryngopharyngeal reflux in obstructive sleep apnea patients

ObjectivesTo determine the effect of continuous positive airway pressure (CPAP) compliance on symptoms and signs of laryngopharyngeal reflux (LPR) in patients with obstructive sleep apnea (OSA).ResultsThirty patients were included. The participants were divided into good compliance (n = 21) and poor compliance (n = 9) groups. After 6-month CPAP treatment, the reflux symptom index score significantly decreased in both the good compliance group (20 (17,24) vs. 14 (10,18), p < 0.001) and the poor compliance group (21 (18,25) vs. 10 (5,16), p < 0.05). Reflux finding score was significantly reduced in both the good compliance group (8 (6,9) vs. 4 (3,5), p < 0.001) and the poor compliance group (6 (4,8) vs. 3 (2,4), p < 0.05). However, there were no statistically significant differences between the groups. CPAP treatment reduces the symptoms and signs of LPR. However, CPAP compliance does not correlate with improvement in LPR in patients with OSA.

0493 A new perspective on exploring the predictive factors of blood pressure reduction during CPAP treatment in OSA

Abstract Introduction The predictive factors of BP response to continuous positive airway pressure (CPAP) in obstructive sleep apnea (OSA) are still being explored. We aimed to assess the antihypertensive effect of CPAP considering the obstructive respiratory event-triggered BP surge profiles in 130 subjects with severe OSA and untreated hypertension. Methods Nocturnal BP was monitored continuously and synchronized with polysomnography. Event-triggered BP surge profiles were studied: BP surge as the value of event-related systolic BP elevation; BP index as the number of BP surge events of ≥10 mmHg per hour. Patients were then divided into two groups according to the median BP index (high and low BP surge groups) and assigned to 4 weeks of CPAP. Changes in BPs and plasma biomarkers were compared. After the initial evaluation, patients with a better BP response in the high BP surge group were then followed up for the second evaluation at 24 months. Results Overall, a modest decrease was observed in both office and asleep BPs at the 4-week follow-up; however, BPs dropped more markedly in patients in high BP surge group than those in low BP surge group, in both office systolic BP (SBP:5.3 mmHg vs.2.2 mmHg, P=.005) and diastolic (DBP:4.0mmHg vs.1.2 mmHg, P=.011), especially the asleep SBP (9.0mmHg vs.2.1 mmHg, P&amp;lt;.001). For 30 cases in the high BP surge group, optimal BP control was achieved in 60.0% of patients and BP &amp;lt; 140/90mmHg reached up to 83.3% after 24 months of CPAP. Linear regression revealed that BP index was significantly associated with BP decrease during CPAP treatment. Conclusion Our results suggest that high event-triggered BP surge was a sensitive predictor of BP response to CPAP in patients with severe OSA and hypertension. Support (if any)

New perspective on exploring the predictive factors of blood pressure reduction during CPAP treatment in people with severe OSA and hypertension: a prospective observational study

BackgroundThe predictive factors of blood pressure (BP) response to continuous positive airway pressure (CPAP) in obstructive sleep apnoea (OSA) are still being explored. We aimed to assess the antihypertensive effect...

Effects of continuous positive airway pressure therapy on left ventricular performance in patients with severe obstructive sleep apnea

We investigated myocardial performance concerning obstructive sleep apnea (OSA) severity and the benefits of continuous positive airway pressure (CPAP) therapy. In this randomized sham-controlled trial, 52 patients (mean age, 49 years; 92%, males; mean AHI, 59) with severe OSA were randomly assigned to receive either CPAP or sham treatment for 3 months. The severity of OSA was determined using the apnea/hypopnea index (AHI), oxygen desaturation index (ODI), percentage of sleep time below 90% oxygen saturation (T90), and average O2 saturation during sleep (mean SpO2). We compared the changes in myocardial work after 3 months of CPAP (n = 26) versus the sham group (n = 26) at rest and during an exercise stress test. Unlike AHI or ODI, indices of hypoxemia including T90 and mean SpO2 were significantly correlated with global constructive work, as defined by work of left ventricle (LV) that contributes to LV ejection during systole (T90, β = 0.393, p = 0.012; mean SpO2, β = 0.331, p = 0.048), and global wasted work (GWW), as defined by work of LV that does not contribute to LV ejection (T90, β = 0.363, p = 0.015; mean SpO2, β = − 0.370, p = 0.019). After 3 months, GWW decreased (80.0 ± 49.2 to 60.8 ± 26.3, p = 0.009) and global work efficiency increased (94.0 ± 4.5 to 95.7 ± 2.0, p = 0.008) in the CPAP group compared to those in the sham group. At the 3-month follow-up exercise stress echocardiography, worsening of GWW during exercise was significantly decreased in the CPAP group compared to that in the sham group (p = 0.045 at 50 W). Hypoxemia indices were closely associated with myocardial performance in patients with severe OSA. CPAP treatment for 3 months improved left ventricular myocardial performance by decreasing wasted work and increasing work efficacy compared to the sham treatment.

Defining the impact of continuous positive airway pressure therapy on diastolic function in adults with moderate-to-severe obstructive sleep apnea.

Although studies have shown that continuous positive airway pressure (CPAP) therapy to treat obstructive sleep apnea improves left ventricular diastolic function, modifiers of improvement are unknown. We explored race and pre-treatment 24-h non-dipping blood pressure status as modifiers of improved diastolic function. Participants (N=220) with obstructive sleep apnea (apnea-hypopnea index ≥15 events/h) and hypertension were recruited to a cohort study that examined effects of 3-month CPAP therapy on 24-h blood pressure. Those who completed echocardiogram at baseline and follow-up were included in this analysis. Diastolic function parameters (E, A, e', E/A, E/e') were assessed. Race was categorised to African American versus others. Participants were categorised as nocturnal dippers (night-time blood pressure decrease by ≥10%) versus non-dippers. We compared changes in parameters of diastolic function by race and nocturnal dipping status. A total of 92 participants were included. They were men (86%), African American (67.4%), and current smoker (29.5%). Mean apnea-hypopnea index was 32.9 events/h. Mean CPAP usage was 3.15 h/day. After 3 months of CPAP treatment, there were significant improvements in measures of diastolic function: a median (interquartile range [IQR]) increase in E velocity by 4.00(-5.75 to 13.75)cm/s, an increase in e' by 2.00(0-4.00)cm/s, and a decrease in the E/e' ratio by 1.74(-4.27 to 0.00) at follow-up (p < 0.05). These changes did not differ by race or nocturnal dipping status. Improvements in diastolic function after CPAP therapy did not differ by race or nocturnal dipping status. Further studies are needed to understand predictors of CPAP effects on diastolic function.

Activity of the telomerase complex before and after CPAP therapy in patients with obstructive sleep apnea syndrome

To evaluate changes in the activity of the telomerase complex in patients with obstructive sleep apnea (OSA) before and after continuous positive airway pressure (CPAP) therapy. In accordance with the objectives of the stages of the study of telomers-telomerase relationships, we maintained the unified design of the study described earlier. The main group 1 (MG1), n=35, consisted of men, aged 53.4 [45.5-60.1] years with characteristic complaints indicating of OSA. The main group 2 (MG2) included the same patients before and after 6 months of CPAP therapy. Blood sampling was performed after the first diagnostic polysomnography (PSG) and after 6 months of CPAP in the morning after the second PSG. The control group (CG) consisted of 26 men, comparable in age and the presence of chronic diseases. Questionnaire, PSG and blood sampling were conducted in CG as well. All participants signed an informed consent. As a result of the STOP-BANG questionnaire conducted before PSG, all patients in the MG1 had scores from 5 to 8. The scores on the Epworth scale were more than 5 points. In the MG2 apnea-hypopnea index decreased from 20.1 to 6.4 ev/hour, the desaturation index decreased from 15.6 to 7.1 ev/hour after 6 months of CPAP. Statistically significant differences in changes in the activity of the telomerase complex were revealed, which after treatment significantly exceed the values of these indicators before treatment. So, telomerase reverse transcriptase value was 0.04 (0.009; 0.06) in the MG1, after treatment it was 0.07 (0.06; 0.09) in the MG2 and 0.134 (0.009; 0.18) in the CG. Telomerase RNA subunit TER1 values were 0.06 (0.03; 0.09), 0.07 (0.05; 0.09) and 0.136 (0.04; 0.17), respectively. However, despite the activation of the telomerase complex during CPAP therapy in patients with OSA, in the CG its activity is significantly higher in comparison with the MG1 and MG2. In OSA accompanied by intermittent hypoxia, a decrease in the activity of the telomerase complex was shown. Elimination of nocturnal hypoxia and improvement of breathing during sleep is accompanied by an increase in the activity of the components of the telomerase complex.

O030 Reduction in fall risk markers following CPAP treatment of obstructive sleep apnoea in people over 65 years

Abstract Objectives Falls in older people can lead to serious injury and significant societal health and financial burden. Obstructive sleep apnoea (OSA) is associated with impaired gait/balance and may increase fall risk, yet few studies examined whether treating OSA reduces fall risk. This study examined the effect of continuous positive airway pressure (CPAP) on fall risk markers in people over 65yrs diagnosed with OSA. Design Single arm intervention study Setting University and tertiary care CPAP clinic. Participants Individuals over 65 years diagnosed with OSA and recommended CPAP. Intervention 3-6 months CPAP therapy Measurements All participants had a physiological profile assessment (PPA) at baseline and following 3-6 months of CPAP. The PPA examines visual contrast sensitivity, lower limb proprioception, knee extension strength, reaction time and postural sway to generate a fall risk score (FRS). t-tests were used to determine difference between pre- and post-treatment FRS. Regression was used to examine the associations between CPAP use and daytime sleepiness with FRS. Results CPAP significantly reduced the FRS ([Mean±SD] 0.59±1.0 vs 0.04±1.1, p=0.016), contrast sensitivity and lower limb proprioception (P&amp;lt;005). Increased CPAP use was associated with improvement in FRS in unadjusted analysis (β=-0.213, 95%CI -0.371 to -0.056, p=0.01). Reduction in Epworth sleepiness score was associated with a reduction in FRS in unadjusted (p=0.02) and adjusted analysis (p&amp;lt;0.03). Conclusions CPAP may reduce fall risk in people over 65yrs, possibly related to better CPAP adherence and reduced daytime sleepiness. Future controlled trials and mechanistic studies are needed to elucidate how CPAP may reduce fall risk.

Obstructive sleep apnea: The key for a better asthma control?

IntroductionObstructive sleep apnea (OSA) is an important risk factor for poor asthma control. The objective of this study is to analyze the symptomatic control in asthmatic patients with OSA after using continuous positive airway pressure (CPAP). MethodsPatients were collected in a monographic asthma consult and a polygraphy was performed due to clinical suspicion or poor disease control. Asthma associated pathologies, as well as clinical and patient-perceived asthma control parameters were evaluated before and after the initiation of CPAP. ResultsA hundred patients were included, 59% were women and 41% men. From them, 54% had severe OSA, 33% moderate OSA and 13% mild OSA, and 10% could not tolerate CPAP. Eighty four percent had a moderate or severe degree of asthma with fractional exhaled nitric oxide (FENO) 32 ± 24.6 ppm and an asthma control test (ACT) before CPAP of 19 ± 4. Asthma control before CPAP was good in 41% of patients, partial in 29%, and bad in 30%. After three or more months of CPAP, clinical asthma control was good in 70% (p < 0.001), perceived control by ACT after CPAP was 21 ± 4 (p < 0.001). When asked for their opinion, 51.5% referred clinical improvement after CPAP, no change in 46.5%. ConclusionsThe use of CPAP in asthmatic patients with OSA improves both clinical and perceived asthma control in a statistically significant way. Most patients had good adaptation to CPAP (90%) and 51.5% had clinical improvement.

Retinal and Choroidal Effects of Continuous Positive Airway Pressure as Treatment for Sleep Apnea: Results at 12 Months.

Background: To determine the impacts of continuous positive airway pressure (CPAP) treatment on retinal and choroidal thickness measurement in individuals with obstructive sleep apnea (OSA). Methods: Participants were 28 patients with OSA treated with CPAP who were enrolled immediately after diagnosis and graded according to the apnea hypopnea index (AHI) determined in an overnight polysomnography. Inclusion criteria were a new diagnosis of OSA and an indication for CPAP. Participants underwent a full ophthalmologic examination including standard automated perimetry (SAP) and optical coherence tomography (OCT) at the levels peripapillary, macular, and choroidal before CPAP onset, and after three and twelve months of CPAP. The data compared before and after treatment were intraocular pressure, SAP, and the thicknesses peripapillary retinal nerve fiber layer (pRNFL), total retinal (TR), retinal ganglion cell layer (RGCL), inner plexiform layer (IPL), photoreceptor layer (PL), and choroidal. Results: After 3 months of CPAP, we observed thickening of the pRNFL (in 5/6 subfields) (p < 0.004) and TR (in 5/9 subfields) (p < 0.010). At 12 months, thickening persisted in these layers, this time affecting 2/6 and 2/9 subfields, respectively (p < 0.012 and p < 0.001, respectively). Choroidal thinning was observed at the temporal level at both 3 and 12 months compared to measurements before starting CPAP treatment (p = 0.014 and p = 0.038, respectively). SAP remained unchanged. Intraocular pressure was higher at 12 months than at 3 months (p = 0.001). Conclusions: 12 months of CPAP avoids retinal thinning and normalizes choroidal thickness in OSA patients.

Reduction in fall risk markers following CPAP treatment of obstructive sleep apnoea in people over 65 years

ObjectivesFalls in older people can lead to serious injury and significant societal health and financial burden. Obstructive sleep apnoea (OSA) is associated with impaired gait/balance and may increase fall risk, yet few studies examined whether treating OSA reduces fall risk. This study examined the effect of continuous positive airway pressure (CPAP) on fall risk markers in people over 65yrs diagnosed with OSA. DesignSingle arm intervention study. SettingUniversity and tertiary care CPAP clinic. ParticipantsIndividuals over 65 years diagnosed with OSA and recommended CPAP. Intervention3–6 months CPAP therapy. Measurements28 participants had a physiological profile assessment (PPA) at baseline and following 3–6 months of CPAP. The PPA examines visual contrast sensitivity, lower limb proprioception, knee extension strength, reaction time and postural sway to generate a fall risk score (FRS). t-tests were used to determine difference between pre- and post-treatment FRS. Regression was used to examine the associations between CPAP use and daytime sleepiness with FRS. ResultsCPAP significantly reduced the FRS ([Mean ± SD] 0.59 ± 1.0 vs 0.04 ± 1.1, p = 0.016), contrast sensitivity and lower limb proprioception (P < 0.05). Increased CPAP use was associated with improvement in FRS in unadjusted analysis (β = −0.213, 95%CI -0.371 to −0.056, p = 0.01). Reduction in Epworth sleepiness score was associated with a reduction in FRS in unadjusted (p = 0.023) and adjusted analysis (adjusted for AHI p = 0.027 or O2Nadir p = 0.015). ConclusionsCPAP may reduce fall risk in people over 65yrs, possibly related to better CPAP adherence and reduced daytime sleepiness. Future controlled trials and mechanistic studies are needed to elucidate how CPAP may reduce fall risk.

Effects of 3-month CPAP therapy on brain structure in obstructive sleep apnea: A diffusion tensor imaging study.

White matter (WM) fiber alterations in patients with obstructive sleep apnea (OSA) is associated with cognitive impairment, which can be alleviated by continuous positive airway pressure (CPAP). In this study, we aimed to investigate the changes in WM in patients with OSA at baseline (pre-CPAP) and 3 months after CPAP adherence treatment (post-CPAP), and to provide a basis for understanding the reversible changes after WM alteration in this disease. Magnetic resonance imaging (MRI) was performed on 20 severely untreated patients with OSA and 20 good sleepers. Tract-based spatial statistics was used to evaluate the fractional anisotropy (FA), mean diffusion coefficient, axial diffusion coefficient, and radial diffusion coefficient (RD) of WM. To assess the efficacy of treatment, 20 patients with pre-CPAP OSA underwent MRI again 3 months later. A correlation analysis was conducted to evaluate the relationship between WM injury and clinical evaluation. Compared with good sleepers, patients with OSA had decreased FA and increased RD in the anterior thalamic radiation, forceps major, inferior fronto-occipital tract, inferior longitudinal tract, and superior longitudinal tract, and decreased FA in the uncinate fasciculus, corticospinal tract, and cingulate gyrus (P < 0.05). No significant change in WM in patients with post-CPAP OSA compared with those with pre-CPAP OSA. Abnormal changes in WM in untreated patients with OSA were associated with oxygen saturation, Montreal cognitive score, and the apnea hypoventilation index. WM fiber was extensively alteration in patients with severe OSA, which is associated with cognitive impairment. Meanwhile, cognitive recovery was not accompanied by reversible changes in WM microstructure after short-term CPAP therapy.

Factors Associated With the Improvement of Left Ventricular Systolic Function by Continuous Positive Airway Pressure Therapy in Patients With Heart Failure With Reduced Ejection Fraction and Obstructive Sleep Apnea

BackgroundObstructive sleep apnea (OSA) is a potential risk factor in cardiovascular diseases, including arrhythmia, coronary artery disease, and heart failure (HF). Continuous positive airway pressure (CPAP) therapy is an effective therapy for OSA and the underlying HF, partly through a 5–9% increase in the left ventricular ejection fraction (LVEF). However, the data on the factors associated with the efficacy of CPAP on LVEF in patients with HF complicated by OSA are scarce. This study aimed to investigate whether LVEF improves in patients with OSA and HF after 1 month of CPAP therapy, and to clarify which factors are associated with the degree of LVEF improvement.MethodThis was a prospective, single-arm, open-label study. We enrolled moderate-to-severe patients with OSA and HF who were being followed up at the cardiovascular center of Toranomon Hospital (Tokyo, Japan). The parameters of sleep study and LVEF were assessed at the baseline and after 1 month of CPAP. The multivariate regression analyses, with changes in LVEF as a dependent variable, were performed to determine the factors that were associated with the degree of LVEF improvement.ResultsWe analyzed 55 consecutive patients with OSA and HF (mean age: 60.7 ± 12.2 years, mean LVEF value: 37.2 ± 9.8%). One month of CPAP treatment decreased the apnea-hypopnea index (AHI) from 45.3 ± 16.1 to 5.4 ± 4.1 per hour, and the LVEF improved from 37.2 ± 9.8 to 43.2 ± 11.7%. The multivariate regression analyses demonstrated that age and body mass index (BMI) were significant determinants of LVEF improvement.ConclusionThe LVEF improved significantly after 1 month of CPAP therapy in Japanese patients with OSA and HF. Multivariate regression analyses indicated that an improvement in LVEF was likely to be observed in young patients with obesity.

Improvements in cognitive function and quantitative sleep electroencephalogram in obstructive sleep apnea after six months of continuous positive airway pressure treatment.

Study ObjectivesUntreated obstructive sleep apnea (OSA) is associated with cognitive deficits and altered brain electrophysiology. We evaluated the effect of continuous positive airway pressure (CPAP) treatment on quantitative sleep electroencephalogram (EEG) measures and cognitive function.MethodsWe studied 167 patients with OSA (age 50 ± 13, AHI 35.0 ± 26.8) before and after 6 months of CPAP. Cognitive tests assessed working memory, sustained attention, visuospatial scanning, and executive function. All participants underwent overnight polysomnography at baseline and after CPAP. Power spectral analysis was performed on EEG data (C3-M2) in a sub-set of 90 participants. Relative delta EEG power and sigma power in NREM and EEG slowing in REM were calculated. Spindle densities (events/min) in N2 were also derived using automated spindle event detection. All outcomes were analysed as change from baseline.ResultsCognitive function across all cognitive domains improved after six months of CPAP. In our sub-set, increased relative delta power (p < .0001) and reduced sigma power (p = .001) during NREM were observed after the 6-month treatment period. Overall, fast and slow sleep spindle densities during N2 were increased after treatment.ConclusionsCognitive performance was improved and sleep EEG features were enhanced when assessing the effects of CPAP. These findings suggest the reversibility of cognitive deficits and altered brain electrophysiology observed in untreated OSA following six months of treatment.

P030 The effects of continuous positive airway pressure (CPAP) therapy in moderate to severe obstructive sleep apnea (OSA): A high-density electroencephalography (EEG) study

Abstract Introduction A previous high-density EEG investigation in OSA showed regional sleep EEG deficits particularly slow wave activity (SWA) in the parietal region. It is unclear whether CPAP treatment can reverse local sleep EEG abnormalities, and whether any recovery is related to improved cognitive function. Methods Fifteen males with moderate-severe OSA (age 50.4±6.5yrs, AHI 51.7±23.5/h) underwent polysomnography with 256-channel high-density EEG at baseline and following 3 months of CPAP. Tasks assessing cognitive performance and sleep-dependent memory were administered. Topographical spectral power maps were calculated for standard frequency ranges for sleep stages. Differences in normalized power between baseline and treatment were determined by statistical nonparametric mapping. Results In 11 CPAP compliant patients (data loss: intolerant of CPAP[n=3]/high-density EEG [n=1]), total sleep time did not change after CPAP but N1 (baseline vs. treatment: 66.9 vs. 39.5 mins, p=0.008) and N2 (195.0 vs. 150.6 mins, p=0.002) sleep was lower and N3 (89.8 vs. 128.7 mins, p=0.003) was higher. Topographic high-density EEG analysis revealed a regional increase in SWA (1–4.5Hz) during N3 sleep in a cluster of 22 electrodes overlying the parietal cortex (paired t-test, t(10)=-3.9, p=0.0029). The change in N3 SWA in the parietal cluster after CPAP was correlated with improved overnight procedural memory on the motor sequence task (rho=0.79, p=0.03) and better executive functioning (Stroop accuracy, rho=0.73, p=0.01). Conclusion CPAP treatment reduces localised deficits in sleep EEG, and specific regional recovery relates to short-term improvements in memory and executive function. These data also highlight the potential for long-term therapeutic effects on cognitive outcomes.

Effets de la ventilation en pression positive continue sur la dépression, l’anxiété et la qualité de vie au cours du syndrome des apnées-hypopnées obstructives du sommeil

IntroductionThe obstructive sleep apnea hypopnea syndrome (OSAHS) is a chronic stressor that may alter the emotional state and quality of life (QOL) of patients suffering from it. In this work, we proposed to estimate the prevalence of depression and anxiety, to assess the QOL in a Tunisian population of apneic patients, and to assess their evolution under continuous positive airway pressure (CPAP). MethodsWe conducted a prospective study, involving 33 apneic patients followed for SAHOS with moderate or severe class disease in the pneumology department at Hedi Chaker university hospital in Sfax, Tunisia. They received CPAP treatment for three months. We used an epidemiological record. Two scales, the Hospital Anxiety and Depression Scale (HADS) and the 36-item Short-Form Health Survey (SF-36), were completed before and after treatment to evaluate the effect of three months of treatment with CPAP. ResultsThe prevalence of depression in the study's patients, according to the HADS, was 45.5% and that of anxiety was 21.2%. After 3months of CPAP, the prevalence of depression and anxiety had become 18.2% and 6.1%, respectively. QOL was impaired in 81.8% of cases before treatment, according to the SF-36. This figure had decreased to 69.7% after 3months of treatment with CPAP. Apart from the third dimension (physical pain), all other dimensions were significantly improved after 3months of CPAP treatment. The treatment with CPAP induced a significant improvement in the average scores of depression (P<0.001), anxiety (P=0.002) and QOL (P<0.001). ConclusionsThese results attest to the importance of the frequency of anxio-depressive disorders as well as an altered QOL in patients with OSAHS. CPAP treatment was shown to be effective in improving these parameters, but this efficacy was partial. Specialized care may be needed in cases of residual anxio-depressive symptoms.

454 Obesity does not modify the effect of 4 months of CPAP on leptin or adiponectin

Abstract Introduction Leptin and adiponectin are cytokines produced by adipocytes. Leptin is involved in the pathogenesis of obesity and adiponectin is cardioprotective. Previous studies in adults with obstructive sleep apnea (OSA) assessing the effect of continuous positive airway pressure (CPAP) on these cytokines are conflicting, and whether obesity modifies the effect remains unknown. We examined the baseline and follow up levels of changes in plasma leptin and adiponectin following 4 months of CPAP treatment among obese (BMI&amp;gt;30) and non-obese (BMI≤30) participants. Methods We evaluated 221 adults (84.6% males) in the Penn Icelandic Sleep Apnea (PISA) Study, with mean (±SD) body mass index (BMI) 31.7±4.9 kg/m2 and apnea-hypopnea index (AHI) 35.7±15.6 events/hour. Associations between changes in natural log of the biomarkers in obese and non-obese participants were evaluated, controlling for a priori baseline covariates of age, baseline BMI, race, sex, site, and current smoking status. Results The mean proportional change (from baseline to follow-up) in log-transformed adiponectin and leptin in CPAP adherent participants was not significantly different between BMI groups. The baseline to follow up change in leptin post-CPAP was 1.01 (95% CI 0.95–1.08) in obese participants and 1.05 (95% CI 0.96–1.14) in non-obese participants. For adiponectin, the change post-CPAP was 1.04 (95% CI 0.95–1.15) in obese participants and 1.08 (95% CI 0.96–1.22) in non-obese participants. Conclusion CPAP treatment did not have an impact on leptin or adiponectin levels. We also find no evidence for obesity modifying the effect of four months of CPAP on leptin or adiponectin. Support (if any) 1P01-1HL094307