Microstructural changes in normal-appearing white matter in male sleep apnea patients are reversible after treatment: A pilot study.

Visually appreciable white matter (WM) changes have been described in obstructive sleep apnea (OSA). However, few data exist on the involvement of silent WM abnormalities. This prospective study investigated the microstructural integrity of normal-appearing white matter (NAWM) in male OSA patients before and after continuous positive airway pressure (CPAP) treatment, using a neuroimaging approach. Magnetic resonance imaging (MRI) was acquired from 32 participants (16 severe never-treated OSA and 16 controls). Diffusion tensor imaging (DTI) and Tract-Based Spatial Statistics (TBSS) were used to assess the microstructural NAWM changes in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). In order to evaluate the efficacy of the therapy, OSA patients underwent MRI evaluations at baseline and after 3 months of treatment (follow-up). CPAP treatment significantly increased the FA in NAWM of the brain stem, corpus callosum and bilateral internal capsule of OSA patients at follow-up compared to baseline (p < 0.05, TFCE-corrected). OSA patients also showed increases in AD in the corpus callosum, superior corona radiata, and internal capsule of the right hemisphere (p < 0.05, TFCE-corrected) after CPAP treatment. A significant negative correlation was found between the FA of the corona radiata, corpus callosum, internal capsule, limbic structures, and neuropsychological scores at follow-up evaluation. No significant differences were found in MD and RD of NAWM in our patients after treatment. Our results demonstrate that FA and AD of NAWM in major tracts such as the corpus callosum and the internal capsule increased significantly after CPAP treatment, as a potential beneficial effect of ventilatory therapy. The recovery of NAWM alterations might also be related to the improvement in the neurocognitive profile, suggesting that nonclearly visible WM alterations may contribute to the physiopathology of OSA-related cognitive impairment.

Changes in Use of Respiratory Support for Preterm Infants in the US, 2008-2018.

Importance: In preterm infants, mechanical ventilation (MV) is associated with adverse pulmonary and neurodevelopmental outcomes. Multiple randomized clinical trials over the past 2 decades have shown the effectiveness of early noninvasive ventilation (NIV) in decreasing the use of MV in preterm infants. The epidemiologic factors associated with respiratory support in US preterm infants and any temporal changes after these trials is unknown. Objective: To evaluate temporal changes in MV and noninvasive respiratory support in US preterm infants. Design, Setting, and Participants: In a cohort design, 2 large national data sets (Pediatrix Clinical Data Warehouse for the clinical cohort and National Inpatient Sample for the national cohort) were used to collect data on preterm infants (<35 weeks' gestation) without congenital anomalies who received active intensive care and were discharged home or died in the birth hospital from January 1, 2008, to December 31, 2018. Data analysis was conducted from December 10, 2019, to December 16, 2020. Exposure: Discharge year. Main Outcome and Measures: In the clinical cohort, detailed respiratory support data were generated, including days of MV and NIV modalities, and temporal trends were evaluated using multivariable modified Poisson or negative binomial regression models with discharge year as a continuous variable. In the national cohort, observed and expected national MV use were calculated. Results: Among 259 311 infants (47.2% female) in 359 neonatal intensive care units in the clinical cohort, decreases were noted in the use (from 29.4% of infants in 2008 to 18.5% in 2018, relative risk for annual change, 0.96; 95% CI, 0.95-0.96) and duration (mean days, from 10.3 in 2008 to 9.7 in 2018; rate ratio for annual change, 0.98; 95% CI, 0.97-0.98) of MV. Noninvasive ventilation use increased from 57.9% of infants in 2008 to 67.4% in 2018 (adjusted relative risk for annual change, 1.02; 95% CI, 1.02-1.03), and mean NIV duration increased by 3.2 days (95% CI, 2.9-3.6 days). With increased use of continuous positive airway pressure and nasal intermittent positive-pressure ventilation as the main factors in the increase, the mean duration of respiratory support increased from 13.8 to 15.4 days (adjusted rate ratio for annual change, 1.03; 95% CI, 1.02-1.04) from 2008 to 2018. Among 1 169 441 infants in the national cohort, MV use decreased from 22.0% in 2008 to 18.5% in 2018, with an estimated 29 700 fewer ventilated infants and 142 000 fewer days of MV than expected during this period. Conclusions and Relevance: These findings suggest that preterm respiratory support changed significantly from 2008 to 2018, with decreased use and duration of MV, increased use and duration of NIV, and an overall increase in respiratory support duration.

Mask side-effects in long-term CPAP-patients impact adherence and sleepiness: the InterfaceVent real-life study.

BACKGROUND: For some patients, Continuous Positive Airway Pressure (CPAP) remains an uncomfortable therapy despite the constant development of technological innovations. To date, no real life study has investigated the relationship between mask related side-effects (MRSEs) and CPAP-non-adherence (defined as < 4 h/day) or residual-excessive-sleepiness (RES, Epworth-Sleepiness-Scale (ESS) score ≥ 11) in the long-term. METHODS: The InterfaceVent-CPAP study is a prospective real-life cross-sectional study conducted in an apneic adult cohort undergoing at least 3 months of CPAP with unrestricted mask-access (34 different masks). MRSEs were evaluated using visual-analogue-scales, CPAP-data using CPAP-software, sleepiness using ESS. RESULTS: 1484 patients were included in the analysis (72.2% male, median age 67 years (IQ25-75: 60-74), initial Apnea-Hypopnea-Index (AHI) of 39 (31-56)/h, residual AHIflow was 1.9 (0.9-4) events/h), CPAP-treatment lasted 4.4 (2.0-9.7) years, CPAP-usage was 6.8 (5.5-7.8) h/day, the prevalence of CPAP-non-adherence was 8.6%, and the prevalence of RES was 16.17%. Leak-related side-effects were the most prevalent side-effects (patient-reported leaks concerned 75.4% of responders and had no correlation with CPAP-reported-leaks). Multivariable logistic regression analyses evaluating explanatory-variable (demographic data, device/mask data and MRSEs) effects on variables-of-interest (CPAP-non-adherence and RES), indicated for patient-MRSEs significant associations between: (i) CPAP-non-adherence and dry-mouth (p = 0.004); (ii) RES and patient-reported leaks (p = 0.007), noisy mask (p < 0.001), dry nose (p < 0.001) and harness pain (p = 0.043). CONCLUSION: In long-term CPAP-treated patients, leak-related side-effects remain the most prevalent side-effects, but patient-reported leaks cannot be predicted by CPAP-reported-leaks. Patient-MRSEs can be independently associated with CPAP-non-adherence and RES, thus implying a complementary role for MRSE questionnaires alongside CPAP-device-reported-data for patient monitoring. Trial registration InterfaceVent is registered with ClinicalTrials.gov (NCT03013283).

Sleep medicine and COVID-19. Has a new era begun?

Since late December 2019, COVID-19, the disease caused by the novel coronavirus, SARS-CoV-2, has spread rapidly around the world, causing unprecedented changes in provided health care services. Patients diagnosed with sleep-disordered breathing (SDB) are subject to a higher risk of worse outcomes from COVID-19, due to the high prevalence of coexistent comorbidities. Additionally, treatment with positive airway treatment devices (PAP) can be challenging because of PAP-induced droplets and aerosol. In this context, sleep medicine practices are entering a new era and need to adapt rapidly to these circumstances, so as to provide the best care for patients with SDB. Novel approaches, such as telemedicine, may play an important role in the management of patients with SDB during the COVID-19 pandemic.

Barriers and enablers of implementing bubble Continuous Positive Airway Pressure (CPAP): Perspectives of health professionals in Malawi.

BACKGROUND: Preterm birth complications are the leading cause of neonatal deaths. Malawi has high rates of preterm birth, with 18.1 preterm births per 100 live births. More than 50% of preterm neonates develop respiratory distress which if left untreated, can lead to respiratory failure and death. Term and preterm neonates with respiratory distress can often be effectively managed with Continuous Positive Airway Pressure (CPAP) and this is considered an essential intervention for the management of preterm neonates by the World Health Organization. Bubble CPAP may represent a safe and cost-effective method for delivering CPAP in low-income settings. OBJECTIVE: The study explored the factors that influence the implementation of bubble CPAP among health care professionals in secondary and tertiary hospitals in Malawi. METHODS: This was a qualitative study conducted in three district hospitals and a tertiary hospital in southern Malawi. We conducted 46 in-depth interviews with nurses, clinicians and clinical supervisors, from June to August 2018. All data were digitally recorded, transcribed verbatim and thematically analyzed. RESULTS: Factors that influenced implementation of bubble CPAP occurred in an interconnected manner and included: inadequate healthcare provider training in preparation for use, rigid division of roles and responsibilities among providers, lack of effective communication among providers and between providers and newborn's caregivers, human resource constraints, and inadequate equipment and infrastructure. CONCLUSION: There are provider, caregiver and health system level factors that influence the implementation of bubble CPAP among neonates in Malawian health facilities. Ensuring adequate staffing in the nurseries, combined with ongoing training for providers, team cohesion, improved communication with caregivers, and improved hospital infrastructure would ensure optimal utilization of bubble CPAP and avoid inadvertent harm from inappropriate use.

Predictors of long-term adherence to continuous positive airway pressure in patients with obstructive sleep apnea and cardiovascular disease.

STUDY OBJECTIVES: Poor adherence to continuous positive airway pressure (CPAP) commonly affects therapeutic response in obstructive sleep apnea (OSA). We aimed to determine predictors of adherence to CPAP among participants of the Sleep Apnea and cardioVascular Endpoints (SAVE) trial. METHODS: SAVE was an international, randomized, open trial of CPAP plus usual care versus usual care (UC) alone in participants (45-75 years) with co-occurring moderate-to-severe OSA (≥12 episodes/h of ≥4% oxygen desaturation) and established cardiovascular (CV) disease. Baseline sociodemographic, health and lifestyle factors, OSA symptoms, and 1-month change in daytime sleepiness, as well as CPAP side effects and adherence (during sham screening, titration week, and in the first month), were entered in univariate linear regression analyses to identify predictors of CPAP adherence at 24 months. Variables with p <0.2 were assessed for inclusion in a multivariate linear mixed model with country, age, and sex included a priori and site as a random effect. RESULTS: Significant univariate predictors of adherence at 24 months in 1,121 participants included: early adherence measures, improvement in daytime sleepiness at 1 month, fixed CPAP pressure, some measures of OSA severity, cardiovascular disease history, breathing pauses, and very loud snoring. While observed adherence varied between countries, adherence during sham screening, initial titration, and the first month of treatment retained independent predictive value in the multivariate model along with fixed CPAP pressure and very loud snoring. CONCLUSIONS: Early CPAP adherence had the greatest predictive value for identifying those at highest risk of non-adherence to long-term CPAP therapy. CLINICAL TRIAL REGISTRATION: SAVE is registered with clinicaltrials.gov (NCT00738179).

Effect of continuous positive airway pressure on inflammatory, antioxidant, and depression biomarkers in women with obstructive sleep apnea: a randomized controlled trial.

STUDY OBJECTIVES: The effect of continuous positive airway pressure (CPAP) on mediators of cardiovascular disease and depression in women with obstructive sleep apnea (OSA) is unknown. We aimed to assess the effect of CPAP therapy on a variety of biomarkers of inflammation, antioxidant activity, and depression in women with OSA. METHODS: We conducted a multicenter, randomized controlled trial in 247 women diagnosed with moderate-to-severe OSA (apnea-hypopnea index [AHI] ≥ 15). Women were randomized to CPAP (n = 120) or conservative treatment (n = 127) for 12 weeks. Changes in tumor necrosis factor α (TNFα), interleukin 6 (IL-6), C-reactive protein (CRP), intercellular adhesion molecule 1 (ICAM-1), catalase (CAT), superoxide dismutase (SOD), and brain-derived neurotrophic factor (BDNF) were assessed. Additional analyses were conducted in subgroups of clinical interest. RESULTS: Women had a median (25th-75th percentiles) age of 58 (51-65) years, body mass index 33.5 (29.0-38.3) kg/m2, and AHI 33.3 (22.8-49.3). No differences were found between groups in the baseline levels of the biomarkers. After 12 weeks of follow-up, there were no changes between groups in any of the biomarkers assessed. These results did not change when the analyses were restricted to sleepy women or to those with severe OSA. In women with CPAP use at least 5 hours per night, only TNFα levels decreased compared to the control group (-0.29 ± 1.1 vs -0.06 ± 0.53, intergroup difference -0.23 [95% CI = -0.03 to -0.50]; p = 0.043). CONCLUSIONS: Twelve weeks of CPAP therapy does not improve biomarkers of inflammation, antioxidant activity, or depression compared to conservative treatment in women with moderate-to-severe OSA. TRIAL REGISTRATION: NCT02047071.

Estimation of early life endogenous surfactant pool and CPAP failure in preterm neonates with RDS.

BACKGROUND: It is not known if the endogenous surfactant pool available early in life is associated with the RDS clinical course in preterm neonates treated with CPAP. We aim to clarify the clinical factors affecting surfactant pool in preterm neonates and study its association with CPAP failure. METHODS: Prospective, pragmatic, blind, cohort study. Gastric aspirates were obtained (within the first 6 h of life and before the first feeding) from 125 preterm neonates with RDS. Surfactant pool was measured by postnatal automated lamellar body count based on impedancemetry, without any pre-analytical treatment. A formal respiratory care protocol based on European guidelines was applied. Clinical data and perinatal risk factors influencing RDS severity or lamellar body count were real-time recorded. Investigators performing lamellar body count were blind to the clinical data and LBC was not used in clinical practice. RESULTS: Multivariate analysis showed gestational age to be the only factor significantly associated with lamellar body count (standardized ß:0.233;p = 0.023). Lamellar body count was significantly higher in neonates with CPAP success (43.500 [23.750-93.750]bodies/µL), than in those failing CPAP (20.500 [12.250-49.750] bodies/µL;p = 0.0003).LBC had a moderate reliability to detect CPAP failure (AUC: 0.703 (0.615-0.781);p < 0.0001; best cut-off: ≤30,000 bodies/µL). Upon adjustment for possible confounders, neither lamellar body count, nor its interaction factor with gestational age resulted associated with CPAP failure. CONCLUSIONS: Early postnatal lamellar body count on gastric aspirates in CPAP-treated preterm neonates with RDS is significantly influenced only by gestational age. Lamellar bodies are not associated with CPAP failure. Thus, the endogenous surfactant pool available early in life only has a moderate reliability to predict CPAP failure.

Marital quality, partner's engagement and continuous positive airway pressure adherence in obstructive sleep apnea.

BACKGROUND: Continuous positive airway pressure (CPAP) is the first line therapy for obstructive sleep apnea (OSA) but its effectiveness requires high adherence. We aimed to assess the impacts of the spouse's/partner's involvement and the quality of the couple's relationship on CPAP adherence. METHODS: In a multicenter prospective study conducted in France, patients reported their subjective views regarding their partner's engagement in their CPAP treatment and the quality of their marital relationship using the Quality of Marriage Index. A hierarchical linear model was built to assess the predictors of CPAP adherence at day 120. Structural equation modeling was performed to evaluate the direct and indirect effects of the spouse's/partner's engagement and the quality of the couple's relationship on CPAP adherence. RESULTS: The 290 OSA patients were predominantly male (77%), with a median age of 53 years IQR: [46; 62], median BMI: 32 kg/m2 [28.6; 35.9] and median apnea + hypopnea index: 43/per hour [33; 58]. Independent factors for CPAP adherence at day 120 were the partner's encouragement of CPAP usage and a stable relationship exceeding 30 years, although emotional support or collaboration were not associated with CPAP adherence. Structural equation modeling demonstrated that spouse's/partner's engagement is directly related to CPAP adherence and improvement of symptoms, and that CPAP adherence is a mediator of disease-specific health-related quality of life. Marital quality was a significant moderator of these interactions meaning that a spouse's/partner's engagement improved adherence only when the quality of marriage index was high. CONCLUSION: Future research and integrated OSA management should systematically include and document the role of the spouse/partner in CPAP adherence.

The impact of continuous positive airway pressure treatment on the recurrence of atrial fibrillation post cardioversion: A randomized controlled trial.

BACKGROUND: Observational data suggest that positive airway pressure (PAP) treatment of obstructive sleep apnea (OSA) can reduce the risk of recurrent atrial fibrillation (AF) post-direct current cardioversion (DCCV) or catheter ablation. METHODS: We conducted a study of adult patients with AF and sleep apnea, stratified by age and gender, who underwent successful DCCV to sinus rhythm, and who were randomized to receive PAP or usual care. Those with sleepiness, significant cardiac or respiratory disease were excluded. Patients were followed for ≤1 year. Primary outcome assessed was time to AF recurrence. Secondary outcomes included sleepiness and quality of life measured using the Epworth Sleepiness Scale (ESS) and Functional Outcome of Sleep Questionnaire (FOSQ) respectively. RESULTS: Of 1757 patients that were screened, 34 underwent polysomnography for this study, 25 of whom had an apnea-hypopnea index (AHI) >5/h. Twelve were randomized to PAP therapy and 13 to usual care. All eligible patients were found to have OSA. There were no differences in body mass index, blood pressure, ejection fraction, AHI, or nocturnal oxygen parameters between intervention and control groups (all p > 0.05). AF recurred in 25% of patients in the PAP and control groups, at 129.0 ±â€¯166.5 versus 109.3 ±â€¯73.2 days respectively, p = 0.98; there were no differences in ESS (5.8 ±â€¯2.6 versus 5.7 ±â€¯2.3; p = 0.17) or FOSQ (18.3 ±â€¯1.5 versus 17.5 ±â€¯1.9; p = 0.26) at follow-up. CONCLUSIONS: This is the first randomized controlled trial assessing the impact of treatment of OSA on recurrence of AF post-DCCV, and did not detect a difference between those treated with PAP versus usual care. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, identifier number: NCT00263757.

How different helmet fixing options could affect patients' pain experience during helmet-continuous positive airway pressure.

BACKGROUND: Prolonged application time of helmet continuous positive airway pressure (CPAP) leads to better outcomes, but its timing can be influenced by the patient's tolerance. AIMS AND OBJECTIVES: To investigate patients' pain and tolerance experience related to different options of helmet fixing system: 'armpits strap' versus 'counterweights system'. DESIGN: This was a non-randomized crossover study performed in a 10-bed intensive care unit and referral extra corporeal membrane oxigenation (ECMO) centre of an Italian university hospital. RESULTS: Twenty patients were enrolled. For helmet-CPAP cycles performed with the armpit straps option, the mean pain numerical rate on a 0-10 scale was: 0·5 ± 1·4 at T0 (baseline), 1·5 ± 2·0 at T1 (after 1 h) and 2·6 ± 2·5 at T2 (end of cycle) (p = 0·023). The same analysis was performed for the counterweights fixing option. The mean score was 0·3 ± 0·6 at T0 , 0·3 ± 0·2 at T1 and 0·5 ± 0·7 at T2 (p = 0·069). The mean duration for CPAP cycles performed with armpits strap and counterweights system was 3·0 ± 1·0 and 3·9 ± 2·3 h, respectively (p < 0·001). The mean section of the Basilic vein that was investigated before wearing the helmet was equal to 0·23 ± 0·20 cm2 . After 1 h of therapy with the counterweight option and armpit straps, the mean increase of the vein's section was 0·27 ± 0·21(p = 0·099) and 0·30 ± 0·25, respectively (p = 0·080). CONCLUSIONS: The fixing system options in use to anchor the helmet during CPAP could worsen the pain experience level and cause device-related pressure ulcers. When compared with the armpit straps option, the counterweights system appears to be a suitable approach to minimize the risks of pressure sores and pain during the treatment. RELEVANCE TO PRACTICE: The helmet CPAP is a reliable therapy to manage acute respiratory failure. Major improvements regarding pulmonary alveolar recruitment and oxygen levels are strictly related to a prolonged time of helmet CPAP cycles. Using a counterweight fixing system, where the armpits straps are not necessary, could be helpful in reducing patients' pain experience.

The Association of Obstructive Sleep Apnea and Pain Outcomes in Adults: A Systematic Review.

Objective: The specific link between obstructive sleep apnea (OSA) and pain is unknown, but it has been hypothesized that OSA patients are hyperalgesic because of fragmented sleep and hypoxemia that enhance sensitivity to pain, promote inflammation, and increase spontaneous pain. We conducted a systematic review of the literature assessing whether OSA is a risk factor for subjective pain intensity and experimental pain tolerance and threshold. Design/Participants: A search of published studies in English in MEDLINE, PubMed, Embase, and the Cochrane Database of Systematic Reviews from database inception through May 2017 was performed. Search terms included "sleep apnea," "continuous positive airway pressure," "CPAP," "pain," and "chronic pain." Methods: We included any study that reported an association between OSA or polysomnogram assessments with pain outcomes or reported the effect of CPAP on pain outcomes. Controlled studies, cohort studies, and case-control studies were included. Results: We identified 448 studies from PubMed and 959 studies from Embase, giving a combined 1,333 studies after removing duplicates. After detailed selection, 28 articles were reviewed in full and 12 met study inclusion criteria. Whereas several studies found an association between OSA and pain intensity or experimental pain, there was considerable variability among study outcomes. Delivery of CPAP may improve pain and decrease opioid use, although the exact nature of the relationship between pain and the various pathophysiologic components of OSA is unclear. Conclusions: This systematic review summarizes the current evidence for the association of OSA and pain outcomes. Further research is needed to identify the differential effects of nocturnal hypoxemia and fragmented sleep on pain intensity. Clinicians might consider screening patients with chronic pain for OSA.

Change in weight and central obesity by positive airway pressure treatment in obstructive sleep apnea patients: longitudinal data from the ESADA cohort.

The effect of positive airway pressure treatment on weight and markers of central obesity in patients with obstructive sleep apnea remains unclear. We studied the change in body weight and anthropometric measures following positive airway pressure treatment in a large clinical cohort. Patients with obstructive sleep apnea with positive airway pressure treatment from the European Sleep Apnea Database registry (n = 1,415, 77% male, age 54 ± 11 [mean ± SD] years, body mass index 31.7 ± 6.4 kg/m2 , apnea-hypopnea index 37 ± 24 n per hr, Epworth Sleepiness Scale 10.2 ± 5.0) were selected. Changes in body mass index and neck/waist/hip circumferences at baseline and at follow-up visit were analysed. Overall, body mass index (0.0 [95% confidence interval, -0.1 to 0.2] kg/m2 ) and neck circumference (0.0 (95% confidence interval, -0.1 to 0.1] cm) were unchanged after positive airway pressure treatment compared with baseline (follow-up duration 1.1 ± 1.0 years and compliance 5.2 ± 2.1 hr per day). However, in non-obese (body mass index <30 kg/m2 ) patients, positive airway pressure treatment was associated with an increased body mass index and waist circumference (0.4 [0.3-0.5] kg/m2 and 0.8 [0.4-1.2] cm, respectively, all p < 0.05), and weight gain was significantly associated with higher positive airway pressure compliance and longer positive airway pressure treatment duration. In the obese subgroup, body mass index was reduced after positive airway pressure treatment (-0.3 [-0.5 to -0.1] kg/m2 , p < 0.05) mainly in patients with a strong reduction in Epworth Sleepiness Scale. In conclusion, positive airway pressure therapy was not found to systematically change body mass index in the European Sleep Apnea Database cohort, but the response was heterogeneous. Our findings suggest that weight gain may be restricted to an obstructive sleep apnea phenotype without established obesity. Lifestyle intervention needs to be considered in both lean and obese patients with obstructive sleep apnea receiving positive airway pressure treatment.

Effect of continuous positive airway pressure on long-term cardiovascular outcomes in patients with coronary artery disease and obstructive sleep apnea: a systematic review and meta-analysis.

BACKGROUND: Obstructive sleep apnea (OSA) is highly prevalent in patients with coronary artery disease (CAD) and is associated with recurrent cardiovascular risk. However, whether treatment with continuous positive airway pressure (CPAP) reduces this risk remains unclear. We performed a systematic review and meta-analysis to assess the effect of CPAP on long-term cardiovascular outcomes in patients with concomitant CAD and OSA. METHODS: We searched the PubMed, EMBASE, and Cochrane library from their inceptions to October 7, 2017. We included observational studies and randomized controlled trials (RCTs) that described the association of CPAP treatment with cardiovascular events in patients with CAD and OSA. The primary outcome of interest was major adverse cardiovascular event (MACE), including all-cause or cardiovascular death, myocardial infarction, stroke, repeat revascularization, or hospitalization for heart failure. Outcomes data were pooled using random effects models and heterogeneity assessed with the I2 statistic. RESULTS: We identified 9 studies (2 RCTs and 7 observational studies) with 1430 participants. The median follow-up duration was from 36 to 86.5 months. Treatment with CPAP was associated with a significantly lower risk of MACE in 6 observational studies (RR 0.61, 95% CI: 0.39-0.94, P = 0.02), but this was not reproduced in 2 RCTs (RR 0.57, 95% CI: 0.32-1.02, P = 0.06). Similarly, CPAP significantly reduced the risk of all-cause death (4 observational studies) and cardiovascular death (3 observational studies), which were also not confirmed in RCTs. CONCLUSIONS: The use of CPAP in patients with CAD and OSA might prevent subsequent cardiovascular events, which was only demonstrated in observational studies, but not in RCTs. The value of CPAP therapy as second prevention for CAD needs further investigation.

Promoting CPAP adherence in clinical practice: A survey of Swedish and Norwegian CPAP practitioners' beliefs and practices.

The benefits of continuous positive airway pressure (CPAP) treatment for obstructive sleep apnea are well established, but adherence tends to be low. Research exploring CPAP practitioners' beliefs around determinants of CPAP adherence, and the actions they use in clinical practice to promote CPAP adherence is lacking. This study aimed to: (i) develop and validate a questionnaire to assess beliefs and current practices among CPAP practitioners; (ii) explore practitioners' beliefs regarding the main determinants of patient adherence, and the actions practitioners most commonly use to promote CPAP adherence; and (iii) explore the associations between perceived determinants and adherence-promotion actions. One-hundred and forty-two CPAP practitioners in Sweden and Norway, representing 93% of all Swedish and 62% of all Norwegian CPAP centres, were surveyed via a questionnaire exploring potential determinants (18 items) and adherence-promotion actions (20 items). Confirmatory factor analysis and second-order structural equational modelling were used to identify patterns of beliefs, and potential associations with adherence-promotion actions. Patients' knowledge, motivation and attitudes were perceived by practitioners to be the main determinants of CPAP adherence, and educating patients about effects, management and treatment adjustments were the most common practices. Knowledge was shown to predict educational and informational actions (e.g. education about obstructive sleep apnea and CPAP). Educational and informational actions were associated with medical actions (e.g. treatment adjustment), but knowledge, attitude and support had no association with medical actions. These findings indicate that a wide variety of determinants and actions are considered important, though the only relationship observed between beliefs and actions was found for knowledge and educational and informational actions.

Changing Faces of Obstructive Sleep Apnea: Treatment Effects by Cluster Designation in the Icelandic Sleep Apnea Cohort.

Study Objectives: Distinct clinical phenotypes of obstructive sleep apnea (OSA) have been identified: Disturbed Sleep, Minimally Symptomatic, and Sleepy. Determining whether these phenotypes respond differently to standard treatment helps us to create a foundation for personalized therapies. We compared responses to positive airway pressure (PAP) therapy in these clinical OSA phenotypes. Methods: The study sample included 706 patients from the Icelandic Sleep Apnea Cohort with moderate-to-severe OSA who were prescribed PAP. Linear and logistic mixed models were used to compare 2-year changes in demographics, comorbid diseases, and sleep-related health issues within and across OSA clinical phenotypes. Relationships between changes in symptoms and PAP adherence were also examined. Results: Overall, effect sizes were moderate to large when comparing sleepiness, insomnia-related, and apneic symptom changes in the Sleepy group with changes in other two groups, especially those in the Minimally Symptomatic group. Within the Disturbed Sleep group, PAP users and nonusers demonstrated similar changes in insomnia-related symptoms. The Minimally Symptomatic group remained relatively asymptomatic, but reported significant decreases in daytime sleepiness and physical fatigue; PAP users generally had larger improvements. The Sleepy group had reductions in nearly all measured symptoms, including large reductions in drowsy driving; almost all of these improvements were greater among PAP users than nonusers. Conclusions: OSA treatment response patterns differed by initial clinical phenotype and PAP adherence. Individuals with insomnia-related symptoms may require additional targeted therapy for these complaints. These findings underscore the need for a personalized approach to management that recognizes patients with a range of OSA presentations.

Changes of vitamin D levels and bone turnover markers after CPAP therapy: a randomized sham-controlled trial.

The aim was to investigate whether continuous positive airway pressure treatment could modulate serum vitamin D (25-hydroxyvitamin D) and bone turnover markers (collagen-type 1 cross-linked C-telopeptide, osteocalcin and N-terminal propeptide of type 1 collagen) in secondary analysis from a randomized controlled trial. Sixty-five continuous positive airway pressure-naïve male patients with obstructive sleep apnea (age = 49 ± 12 years, apnea-hypopnea index = 39.9 ± 17.7 events h-1 , body mass index = 31.3 ± 5.2 kg m-2 ) were randomized to receive either real (n = 34) or sham (n = 31) continuous positive airway pressure for 12 weeks. At 12 weeks, all participants received real continuous positive airway pressure for an additional 12 weeks. After 12 weeks of continuous positive airway pressure (real versus sham), there were no between-group differences for any of the main outcomes [Δ25-hydroxyvitamin D: -0.80 ± 5.28 ng mL-1 (mean ± SE) versus 3.08 ± 3.66 ng mL-1 , P = 0.42; Δcollagen-type 1 cross-linked C-telopeptide: 0.011 ± 0.014 ng mL-1 versus -0.004 ± 0.009 ng mL-1 , P = 0.48; Δosteocalcin: 1.13 ± 1.12 ng mL-1 versus 0.46 ± 0.75 ng mL-1 , P = 0.80; ΔN-terminal propeptide of type 1 collagen: 2.07 ± 3.05 µg L-1 versus -1.05 ± 2.13 µg L-1 , P = 0.48]. There were no further differences in subgroup analyses (continuous positive airway pressure-compliant patients, patients with severe obstructive sleep apnea or sleepy patients). However, after 24 weeks irrespective of initial randomization, vitamin D increased in patients with severe obstructive sleep apnea (9.56 ± 5.51 ng mL-1 , P = 0.045) and in sleepy patients (14.0 ± 4.69 ng mL-1 , P = 0.007). Also, there was a significant increase in osteocalcin at 24 weeks (3.27 ± 1.06 ng mL-1 , P = 0.01) in compliant patients. We conclude that 12 weeks of continuous positive airway pressure did not modulate vitamin D or modulate any of the bone turnover markers compared with sham. However, it is plausible that continuous positive airway pressure may have late beneficial effects on vitamin D levels and bone turnover markers in selected groups of patients with obstructive sleep apnea.

Effects of Positive Airway Pressure and Mechanical Ventilation of the Lungs During Cardiopulmonary Bypass on Pulmonary Adverse Events After Cardiac Surgery: A Systematic Review and Meta-Analysis.

OBJECTIVE: To investigate whether different ventilation strategies during cardiopulmonary bypass (CPB) can improve outcomes in adult cardiac surgery patients. DESIGN: Systematic review of randomized controlled trials with meta-analyses. SETTING: Clinical trials for human studies up to July 2016 were obtained from electronic databases (Medline, Embase, PubMed, and the Cochrane Central Register of Controlled Trials) and reference lists of relevant randomized trials and review articles. PARTICIPANTS: Adult patients undergoing cardiac surgery. INTERVENTIONS: Patients who underwent cardiac surgery with CPB and ventilation or continuous positive airway pressure (CPAP). MEASUREMENTS AND MAIN RESULTS: Fifteen randomized controlled trials with 748 patients were analyzed. In cardiac surgery, CPAP use during CPB was associated with an improved alveolar-arterial oxygen gradient difference compared with no CPAP (weighted mean difference [WMD] = 4.11 kPa; 95% confidence interval [CI] = 0.85-7.37; I2 = 28.8%). Ventilation during CPB did not improve the postoperative hypoxemia score (WMD = 30.94; 95% CI = -20.76 to 82.63; I2 = 61%) or diffusion capacity compared with the apnea group (WMD = 2.59 kPa; 95% CI = -2.49 to 7.67; I2 = 81.3%). Neither CPAP nor ventilation during CPB was associated with a shorter mechanical ventilation time or hospital stay. CONCLUSIONS: CPAP during CPB improved the alveolar-arterial oxygen gradient difference compared with apnea, but ventilation during CPB did not. Neither CPAP nor ventilation during CPB demonstrated evidence of improving clinical outcomes in low- or intermediate-risk patients for elective cardiac surgery. The findings are inconclusive because of heterogeneity and small sample sizes.