Long-term adherence to continuous positive airway pressure therapy in non-sleepy sleep apnea patients

ObjectiveThe effectiveness of continuous positive airway pressure (CPAP) therapy greatly depends on consistent use. However, data regarding adherence in non-sleepy obstructive sleep apnea (OSA) patients are scarce. The aim of this study was to assess long-term adherence and predictors of CPAP compliance in a large sample of non-sleepy OSA patients.MethodsWe conducted a prospective, multicenter study comprising 357 non-sleepy patients (Epworth Sleepiness Scale score <11) with moderate-to-severe OSA (apnea–hypopnea index [AHI] of ≥20) who began CPAP therapy between May 2004 and May 2006; follow-up ended in May 2009. Non-compliance was scored as CPAP dropout or average cumulative CPAP use of <4 hours per night. Multivariate Cox regression analysis was performed to identify independent predictors of poor CPAP adherence.ResultsPatients were followed up for a median of four years (interquartile range [IQR] = 3.0–4.4). At the end of the study period, 230 patients (64.4%) fulfilled the criteria for good CPAP compliance, whereas 127 patients (35.6%) were considered non-compliant. The median CPAP use was five hours per night (interquartile range = 2.18–6.25). Multivariate analysis showed that interactions between the AHI and the percentage of nighttime spent with an O₂ saturation of <90% (TC90) (p = 0.010) and between the AHI and hypertension at baseline (p = 0.029) predicted long-term compliance with CPAP.ConclusionThis study demonstrates that CPAP treatment is feasible in non-sleepy, moderate-to-severe OSA patients. Good CPAP adherence was predicted by greater OSA severity as measured by both the AHI and TC90 and by the presence of hypertension at baseline in patients with higher AHI levels.     

Prevalence of obstructive sleep apnea in patients with posttraumatic stress disorder and its impact on adherence to continuous positive airway pressure therapy: a meta-analysis

ObjectiveAlthough some authors have recently investigated the co-occurrence of posttraumatic stress disorder (PTSD) and obstructive sleep apnea (OSA), the topic remains insufficiently studied. The aim of this meta-analysis was to detect the pooled prevalence of OSA in PTSD and its impact on adherence to continuous positive airway pressure (CPAP) therapy.MethodsWe conducted a search for articles published until August 20, 2016, in PubMed, Embase, the Cochrane Library, and PsycINFO. The literature search identified 194 articles, and 12 studies were included in the meta-analysis.ResultsThe pooled prevalence rates of OSA based on different apnea–hypopnea index (AHI) criteria in PTSD patients was 75.7% (95% confidence interval [CI] = 44.1–92.5%) (AHI ≥5) and 43.6% (95% CI = 20.6–69.7%) (AHI ≥10), respectively. Subgroup analysis showed that there was a significant difference between the prevalence of OSA in veterans with PTSD compared to nonveterans or mixed samples. Patients with PTSD and OSA demonstrated significantly lower adherence to CPAP therapy (regular use: g = −0.658, 95% CI = −0.856 to −0.460; time of average use per night: g = −0.873, 95% CI = −1.550 to −0.196) compared with those with OSA alone.ConclusionsOSA is commonly seen in patients with PTSD. Given its negative impact on the adherence to CPAP therapy, the possibility of OSA should be monitored carefully in patients with PTSD.     

Continuous positive airway pressure treatment and anxiety in adults with coronary artery disease and nonsleepy obstructive sleep apnea in the RICCADSA trial

BackgroundAnxiety and obstructive sleep apnea (OSA) coexist among adults with coronary artery disease (CAD) following revascularization. Continuous positive airway pressure (CPAP) is the first line treatment of OSA patients with daytime sleepiness. The current study evaluated the effect of CPAP on anxiety in CAD patients with nonsleepy OSA.MethodsTwo hundred forty-four revascularized CAD patients with nonsleepy OSA (apnea-hypopnea index ≥15/h, Epworth Sleepiness Scale score <10) were randomly assigned to CPAP or no-CPAP between 2005 and 2010. Zung Self-rating Anxiety Scale (SAS) was administered at baseline and after 3 and 12 months with higher scores suggesting more anxiety.ResultsA total of 208 patients with complete SAS scores at baseline and 12-month follow-up were included (CPAP, n = 103; no-CPAP, n = 105). In the intention-to-treat analysis, CPAP had no significant effect on the SAS scores. On-treatment analysis revealed a significant increase in the median of delta SAS score (+3.75) after three months among the participants using the device 2.8 h/day or more while there was a decline in the median of delta SAS score (−1.25) in the non-adherent or no-CPAP group (p = 0.031). The increase in the SAS score (+1.25) in the adherent group, and the decline (−1.25 points) in the non-adherent/no-CPAP group remained significant after one year (p = 0.011). Baseline SAS score predicted non-adherence [adjusted odds ratio 1.11; 95% confidence interval (CI) 1.04–1.18; p = 0.003], and there was an association between the increase in the SAS scores and accumulated CPAP hours/day [standardized β = 0.144 (95% CI 0.005–0.695), p = 0.047].ConclusionOur results suggest that anxiety should be considered in the management of CAD patients with nonsleepy OSA following revascularization.Clinical trial registrationNCT00519597.     

Obstructive sleep apnea,CPAP therapy and Parkinson's disease motor function: A longitudinal study

IntroductionWe aimed to assess, in patients with Parkinson's disease (PD), the association between obstructive sleep apnea (OSA), progression of motor dysfunction and the effect of OSA treatment.MethodsData were analysed from a prospective cohort study of idiopathic PD patients from a movement disorders clinic. Patients found to have OSA on polysomnography (apnea-hypopnea index [AHI] ≥15 events/h, OSA+) were offered treatment using continuous positive airway pressure (CPAP). CPAP+ was defined as an average ≥ 2 h/night use at each follow-up. Motor symptoms were assessed using the motor section of the Movement Disorder Society Unified Parkinson's Disease Rating Scale (mUPDRS) and the Timed-Up-And-Go (TUG). Follow-up times were 3, 6 and 12 months. Mixed models were constructed, adjusting for age, sex, body mass index, levodopa equivalent dose and comorbidities.ResultsWe studied 67 individuals (61.2% male) of mean age 64.7 years (SD = 10.1). Baseline mUPDRS was higher in OSA+ compared to OSA- (24.5 [13.6] vs. 16.2 [7.2], p < 0.001). Motor dysfunction increased at comparable rates in OSA- and OSA+CPAP-. However, in OSA+CPAP+, mUPDRS change was significantly lower compared to OSA- (β = −0.01 vs. 0.61, p = 0.03; p = 0.12 vs. OSA+CPAP- [β = 0.39]) and TUG change was lower compared to OSA+CPAP- (β = −0.01 vs. 0.13, p = 0.002; p = 0.05 vs. OSA- [β = 0.02]).ConclusionsIn this PD cohort, OSA was associated with higher baseline mUPDRS. In those with OSA, CPAP use was associated with stabilization of motor function (mUPDRS and TUG) over 12 months. These observations support further research to clarify the role of OSA in PD pathophysiology and motor dysfunction.     

Severity of individual obstruction events increases with age in patients with obstructive sleep apnea

BackgroundAge is a risk factor of obstructive sleep apnea (OSA). It has been shown that OSA progresses over time, although conflicting results have been reported. However, the effect of age on the severity of OSA and individual obstruction events has not been investigated within different OSA severity categories by taking the most prominent confounding factors (i.e., body mass index, gender, smoking, daytime sleepiness, snoring, hypertension, heart failure, and proportion of supine sleep) into account.MethodsPolygraphic data of 1090 patients with apnea–hypopnea index (AHI) ≥5 were retrospectively reanalyzed. The effect of age on the severity of OSA and obstruction events was investigated in general, within different OSA severity categories, and in different age groups (age <40, 40≤ age <50, 50≤ age <60, and age ≥60 years).ResultsIn the whole population, AHI and durations of apneas, hypopneas, and desaturations increased with increasing age (B ≥ 0.108, p ≤ 0.010). In more detailed analysis, AHI increased with age only in the moderate OSA category (B = 0.075, p = 0.022), although durations of apneas increased in mild and severe OSA categories (B ≥ 0.076, p ≤ 0.038). Furthermore, durations of hypopneas increased with age in mild and moderate OSA categories (B ≥ 0.105, p ≤ 0.038), and durations of desaturations (B ≥ 0.120, p ≤ 0.013) in all OSA severity categories. AHI was not statistically significantly different between the age groups, although durations of obstruction events tended to increase towards older age groups.ConclusionAs obstruction event severity was more strongly dependent on the age than it was dependent on AHI, considering the severity of obstruction events could be beneficial while estimating the long-term effects of the treatments and prognosticating the disease progression.     

Clinical and polysomnographic characteristics and response to continuous positive airway pressure therapy in obstructive sleep apnea patients with nightmares

ObjectiveTo assess the characteristics of obstructive sleep apnea (OSA) patients with nightmares and the effects of continuous positive airway pressure (CPAP) therapy on nightmares.MethodsConsecutive patients referred with a clinical suspicion of OSA underwent attended overnight sleep studies. OSA and nightmares were diagnosed according to the American Academy of Sleep Medicine (AASM) criteria, and CPAP titration was performed in accordance with the AASM guidelines. A follow-up visit was performed 3 months later, and the patients with nightmares were divided into two groups: group 1 used CPAP with good compliance, whereas group 2 refused CPAP treatment and did not use other alternative treatments for OSA.ResultsThe study included 99 patients who had been diagnosed with OSA with nightmares. Their mean age was 47.2 ± 11.2 years, and they had a mean apnea–hypopnea index (AHI) of 36.5 ± 34.3/h. Also included were 124 patients with OSA without nightmares. The mean age of these patients was 45.4 ± 13.9 years, and they had a mean AHI of 40.2 ± 35/h. The patients with nightmares had a significantly higher AHI during rapid eye movement sleep (REM) compared with the patients without nightmares (51.7 ± 28.1 vs 39.8 ± 31.9/h). Logistic regression analysis revealed that the REM-AHI and interrupted sleep at night were independent predictors of nightmares in the OSA patients. Nightmares disappeared in 91% of the patients who used CPAP compared with 36% of patients who refused to use CPAP (p < 0.001).ConclusionNightmares in OSA patients are associated with a higher REM-AHI. CPAP therapy results in a significant improvement in nightmare occurrence.     

Prevalence and determinants of subjective sleepiness in healthy elderly with unrecognized obstructive sleep apnea

ObjectiveObstructive sleep apnea (OSA) is associated with behavioral consequences such as excessive daytime sleepiness (EDS). The aim of this study was to establish the presence of sleepiness in elderly with unrecognized OSA and the factors explaining its occurrence.MethodologyA total of 825 healthy elderly (aged ≥65 years) undergoing clinical, respiratory polygraphy, and heart-rate variability analysis were studied. According to the apnea–hypopnea index (AHI), the subjects were stratified in four categories: no-OSA (AHI <5), mild (5 > AHI <15), moderate (15 ≥ AHI <30), and severe OSA (AHI ≥30). Participants with EDS were defined on the basis of the Epworth Sleepiness Scale (ESS) score ≥10.ResultsOverall, the mean ESS score was 5.7 ± 5.6, 14.9% showing EDS with an increasing trend according to OSA severity (p <0.001). Sleepy subjects were more frequently men, having a greater body mass index (BMI), alcohol intake, depression score, and indices of OSA severity (23% of severe OSA cases being sleepy). No differences were present between sleepy and non-sleepy subjects in regard to other clinical, metabolic, and autonomic nervous system measurements. Regression analyses adjusted for age, gender, BMI, hypertension, depression score, autonomic sleep fragmentation, and AHI and/or oxygen desaturation index revealed that gender (p <0.0001), depression score (p <0.0001), and BMI (p = 0.01) were the only significant factors affecting the presence of sleepiness in this population.ConclusionsIn healthy elderly with OSA, the prevalence of EDS was low, and it affected only severe cases. Despite a weak association between the ESS score and the AHI index, male gender and depression score were the most significant predictors for the occurrence of sleepiness.     

A randomized,controlled trial of positional therapy versus oral appliance therapy for position-dependent sleep apnea

ObjectiveTo compare the effectiveness of positional therapy (PT) with the sleep position trainer (SPT) to oral appliance therapy (OAT) in patients with mild-to-moderate positional obstructive sleep apnea (POSA).MethodsMulticenter, prospective, randomized, controlled trial. Patients with mild-to-moderate POSA (apnea-hypopnea index (AHI) ≥5 ≤ 30/hour sleep) were randomized for PT or OAT. Polysomnography was repeated after 3 months. Efficacy, adherence, mean disease alleviation (MDA), quality of life, dropouts and adverse events were evaluated.ResultsA total of 177 patients were screened for the study; 99 underwent randomization and 81 completed the study. Intention-to-treat (ITT) analysis of median [IQR] AHI showed a reduction in the PT group from 13.0 [9.7–18.5] to 7.0 [3.8–12.8], p < 0.001 and in the OAT group from 11.7 [9.0–16.2] to 9.1 [4.9–11.7], p < 0.001. Mean adherence (≥4 h/night, ≥5 days/week) was 89.3 ± 22.4% for SPT versus 81.3 ± 30.0% in OAT patients, p = 0.208.ConclusionsOral appliance therapy and positional therapy were equally effective in reducing the median AHI in patients with mild-to-moderate POSA. The results of this study have important implications for future OSA treatment guidelines and daily clinical practice.ClinicalTrials.gov numberNCT02045576.     

Multiscale entropic assessment of autonomic dysfunction in patients with obstructive sleep apnea and therapeutic impact of continuous positive airway pressure treatment

ObjectiveObstructive sleep apnea (OSA) is an independent risk factor for cardiovascular disease because of its associated autonomic nervous and vascular regulatory dysfunctions. We tested the hypothesis that the multiscale entropy (MSE) approach to heart rate variability analysis may be used for evaluating OSA severity through simultaneous assessment of these abnormalities.MethodsA total of 147 subjects were divided into four groups according to apnea–hypopnea index (AHI) from polysomnography (PSG): Snoring without OSA (5 > AHI, n = 31), mild (5 ≤ AHI < 15, n = 31), moderate (15 ≤ AHI < 30, n = 41), and severe (AHI ≥ 30, n = 44) OSA. Of the patients, 41 receiving continuous positive airway pressure (CPAP) treatment were included for comparison. For each subject, two segments of electrocardiographic (ECG) signals (both at stage N2) were used for R-R interval (RRI) analysis, including a 10-minute recording 10 minutes after falling asleep (ie, early phase) and another 10-minute segment at 3 hours (ie, late phase). Heart rate variability as reflected in changes in RRI between the two segments was assessed with small-scale multiscale entropy index (MEI_SS, sum of sample entropy from time scale from 1 to 5) and large-scale multiscale entropy index (MEI_LS, scale from 6 to 10).ResultsIncrease in MEI_LS in the late phase of sleep was noted in both the normal snoring and CPAP groups (P <0.01). Although the moderate OSA group exhibited MEI_SS drop in the late phase (P < 0.02), both MEI_SS and MEI_LS decreased in the late phase in the severe OSA group (P < 0.001, P < 0.02). However, no differences were noted in mild OSA subjects in both parameters.ConclusionThe results demonstrated significant severity-dependent deterioration in autonomic and vascular regulatory function in patients with OSA as reflected in the reductions in MEI_SS and MEI_LS, respectively, and notable improvement after CPAP treatment. The MEI obtainable through PSG may indicate not only OSA severity and physiological status but also therapeutic outcome for OSA patients.     

Total durations of respiratory events are modulated within REM and NREM sleep by sleeping position and obesity in OSA patients

BackgroundSupine sleeping position and obesity are well-known risk factors for obstructive sleep apnea (OSA) and modulate the risk for OSA-related daytime symptoms. Although respiratory event durations are associated with OSA-related severe health consequences, it is unclear how sleeping position, obesity, and daytime sleepiness are associated with respiratory event durations during REM and NREM sleep. We hypothesize that irrespective of the apnea-hypopnea index (AHI), respiratory event durations differ significantly between various OSA subgroups during REM and NREM sleep.MethodsOne night in-lab polysomnographic recordings were retrospectively analyzed from 1910 untreated suspected OSA patients. 599 patients (AHI ≥ 5) were included in study and divided into subgroups based on positional dependency, BMI, and daytime sleepiness (Epworth Sleepiness Scale and Multiple Sleep Latency Test). Differences in total hypopnea time (THT), total apnea time (TAT), and total apnea-hypopnea time (TAHT) within REM and NREM sleep between the subgroups were evaluated.ResultsDuring REM sleep, positional OSA patients had lower THT (OR = 0.952, p < 0.001) and TAHT (OR = 0.943, p < 0.001) than their non-positional counterparts. Compared to normal-weight patients (BMI < 25 kg/m²), obese patients (BMI ≥ 30 kg/m²) had lower THT, TAT, and TAHT (ORs = 0.942–0.971, p ≤ 0.009) during NREM sleep but higher THT (OR = 1.057, p = 0.001) and TAHT (OR = 1.052, p = 0.001) during REM sleep. No significant differences were observed in THT, TAT, and TAHT between patients with and without daytime sleepiness.ConclusionRegardless of the AHI, respiratory event durations vary significantly between OSA sub-groups during REM and NREM sleep. Therefore, to personalize OSA severity estimation the diagnosis should be tailored based on patient's demographics, clinical phenotype, and PSG characteristics.     

Does CPAP treatment in mild obstructive sleep apnea affect blood pressure?

ObjectivesObstructive sleep apnea (OSA) is associated with significant cardiovascular (CV) morbidity. Continuous positive airway pressure (CPAP) is the standard treatment for moderate to severe OSA, resulting in a reduction in CV morbidity. No studies have compared CV outcomes between CPAP and no CPAP in mild OSA (5 ? AHI < 15).MethodsRetrospective cohort study of subjects (age ? 18) with mild OSA diagnosed between 2004 and 2006. Subjects with a history of hypertension, angina, stroke and smoking were excluded. Subjects were stratified into two groups: CPAP (n = 93) or no CPAP (n = 162). The mean blood pressures (MBP) were compared 2 years after the diagnosis of OSA was established.ResultsUnmatched for covariates (age, sex, BMI, neck circumference, AHI, arousal index and family h/o CV disorders), subjects with mild OSA on CPAP had a 1.97 point reduction, and no CPAP resulted in a 9.61 point elevation (p < 0.0001) in MBP. With propensity score matching for covariates, the mean difference in MBP was ?1.97 (95% CI: ?14.03, ?9.92; p < 0.0001) with a sensitivity analysis of 2.646.ConclusionThis study shows an elevation of the MBP in mild OSA patients who were not treated with CPAP. CPAP treatment in mild OSA patients decreased the MBP over a 2-year period.     

Moderate-to-severe obstructive sleep apnea is associated with subclinical myocardial injury and impaired hemodynamics in pulmonary hypertension patients

BackgroundThe clinical significance of obstructive sleep apnea (OSA) in pulmonary hypertension (PH) patients remains unclear. We investigated the hemodynamics and serum troponin T concentrations associated with OSA in PH patients.MethodsCross-sectional study was performed on data from 97 clinically stable PH patients. Using overnight sleep study, we evaluated apnea–hypopnea index (AHI) and divided patients into two groups: none-to-mild OSA (AHI < 15/h, N = 81) and moderate-to-severe OSA (AHI ≥ 15/h, N = 16). Clinical, hemodynamic, and laboratory data were compared with OSA severity.ResultsModerate-to-severe OSA patients had higher pulmonary vascular resistance (PVR; 6.5 [5.7–12.9] vs 4.4 [2.9–6.4] Wood units, p = 0.001) and mean pulmonary artery pressure (mPAP; 37 [30–49] vs 30 [22–37] mmHg, p = 0.045), and a lower cardiac index (2.2 [1.6–2.6] vs 2.8 [2.3–3.5] L/min/m², p = 0.001) than those without. There was no association between plasma B-type natriuretic peptide (BNP) or serum C-reactive protein levels and OSA. However, high-sensitivity troponin T (hs-TnT) level was significantly higher in moderate-to-severe OSA patients (13 [8–18] vs 6 [4–10] ng/L, p <0.001). The hs-TnT level positively correlated with the plasma BNP level, mPAP, PVR, AHI, obstructive apnea index, and 6-min walking distance. After adjustment for age, estimated glomerular filtration rate, hypertension, smoking, and plasma BNP level, moderate-to-severe OSA was an independent factor for determining the plasma level of log hs-TnT level (β = 0.419, 95% confidence interval 0.119–0.718, p = 0.007).ConclusionsModerate-to-severe OSA is associated with impaired hemodynamics and subclinical myocardial damage in PH patients. Thus, OSA-related myocardial injury may play a role in hemodynamic destabilization with its associated poor prognosis.     

Does CPAP treat depressive symptoms in individuals with OSA? An analysis of two 12-week randomized sham CPAP-controlled trials

BackgroundDepression is common in patients with obstructive sleep apnea (OSA). Whether treating OSA with continuous positive airway pressure (CPAP) improves depressive symptoms remains inconclusive. We examined the impact of CPAP on depressive symptoms in OSA patients compared to sham CPAP.MethodsA sub-analysis of two previous randomized sham-controlled trials was conducted. 126 male OSA patients (age = 51 ± 11 years; BMI = 32.0 ± 5.1 kg/m²; apnea hypopnea index = 42.4 ± 22.6 events/hour) were randomised either to therapeutic CPAP (n = 65) or sham CPAP (n = 61). Depressive symptoms were measured using the Depression, Anxiety and Stress Scale (DASS). The main outcome was the change in the DASS depression score (DASSD) after three months between the therapeutic and sham CPAP arms.ResultsThe change in DASSD at three months did not differ between therapeutic and sham CPAP (mean difference: 0.5, 95% CI -3.6 to 4.6, p = 0.80). There was no significant between-group differences within the sub-groups of adherent users (device usage≥4hrs/day), or those with baseline depression (DASSD>9). In a secondary analysis of patients with baseline depression, adherent therapeutic CPAP use was associated with a greater reduction in DASSD scores compared to non-adherers (−10.0, 95% CI -18.3 to −1.8, p = 0.019). Conclusions: Overall, three months of CPAP did not significantly improve depression scores in OSA patients. Adherent use of therapeutic CPAP in patients with baseline depressive symptoms was associated with a reduction in symptom score. Future trials involving OSA patients with higher depressive symptoms will enable us to understand the complex interaction between OSA and depression.     

Anticyclic modulated ventilation versus continuous positive airway pressure in patients with coexisting obstructive sleep apnea and Cheyne–Stokes respiration: a randomized crossover trial

BackgroundAlthough coexisting obstructive sleep apnea (OSA) and Cheyne–Stokes respiration (CSR) occur frequently in patients with heart diseases, optimal treatment remains unclear. Positive airway pressure (PAP) effectively treats OSA and adaptive servo-ventilation (ASV) has been shown to improve CSR. We compared a new treatment algorithm combining automatic continuous positive airway pressure (APAP) and ASV (anticyclic modulated ventilation, ACMV) versus continuous positive airway pressure (CPAP).MethodsThirty-nine patients (35 male, four female; aged 65.5 ± 9.7 years; body mass index, 31.0 ± 5.9 kg/m²) with underlying heart disease and coexisting OSA and CSR were enrolled. After diagnostic polysomnography (PSG) and CPAP titration, patients were randomized either to CPAP or to ACMV for four weeks of treatment in a crossover design.ResultsTotal apnea–hypopnea index (AHI) was 49.0 ± 18.8/h at baseline, 12.3 ± 14.6/h with CPAP (P < 0.001 vs baseline), and 3.7 ± 5.6/h with ACMV (P < 0.001 vs baseline and vs CPAP). Obstructive AHI was 20.7 ± 14.4/h at baseline, 5.1 ± 9.3/h with CPAP (P < 0.001 vs baseline), and 0.4 ± 0.4/h with ACMV (P < 0.001 vs baseline and vs CPAP). Central AHI was 28.3 ± 13.4/h at baseline, 7.2 ± 9.7/h with CPAP (P < 0.001 vs baseline) and 3.3 ± 5.4/h with ACMV (P < 0.001 vs baseline and vs CPAP). Ejection fraction was increased significantly (from 38.6 ± 15.6 to 44.4 ± 12.2%) only with ACMV. Subjective sleepiness significantly improved only with CPAP whereas objective sleep quality and treatment adherence were not different between both treatment modalities.ConclusionACMV is an effective treatment option in patients with coexisting OSA and CSR. It is superior to CPAP in reducing total AHI as well as obstructive and central AHI.     

Identifying obstructive sleep apnea after stroke/TIA: evaluating four simple screening tools

ObjectiveDespite its high prevalence and unfavorable clinical consequences, obstructive sleep apnea (OSA) often remains underappreciated after cerebrovascular events. The purpose of our study was to evaluate the clinical utility of four simple paper-based screening tools for excluding OSA after stroke or transient ischemic attack (TIA).Patients/MethodsSixty-nine inpatients and outpatients with stroke or TIA during the past 180 days completed the 4-Variable screening tool (4V), STOP-BAG questionnaire (ie, STOP-BANG questionnaire without the neck circumference measurement), Berlin questionnaire, and the Sleep Obstructive apnea score optimized for Stroke (SOS). They subsequently underwent objective testing using a portable sleep monitoring device. Cutoffs were selected to maximize sensitivity and exclude OSA (AHI ≥ 10) in ≥10% of the cohort.ResultsThe mean age was 68.3 ± 14.2 years and 47.8% were male. Thirty-two patients (46.4%) were found to have OSA. Male sex, body mass index (BMI), and atrial fibrillation were independent predictors of OSA. Among the screening tools, the 4V had the greatest area under the curve (AUC) of 0.688 (p = 0.007); the sensitivity was 96.9% for a cutoff of <6. The STOP-BAG also significantly detected OSA with an AUC of 0.677 (p = 0.012); the sensitivity was 93.8% for a cutoff of <2. Scores on the 4V and STOP-BAG were significantly correlated with the AHI.ConclusionsThe 4V and STOP-BAG questionnaire may aid clinicians with ruling out OSA within 180 days of stroke/TIA. Due to the atypical presentation of poststroke/TIA OSA, these tools are only moderately predictive; objective testing should still be used for OSA diagnosis in this population.     

Management and outcome of extreme pediatric obstructive sleep apnea

ObjectivesClassify post-adenotonsillectomy (AT) respiratory support, identify variables that predict these interventions, and evaluate outcomes in children with extreme obstructive sleep apnea (OSA).MethodsRetrospective chart analysis was performed on patients found to have apnea/hypopnea index (AHI) > 100 events/h. Patients with chronic diseases other than obesity were excluded.ResultsForty-one subjects were studied, average age of 11.4 ± 4.3 years, majority (73.1%) were Hispanic, with a mean total AHI (TAHI) of 128.1 ± 22.9/h. Twenty-eight (68.3%) patients underwent AT. Lower age (P < 0.001), lower BMI Z-score (P < 0.01), higher OAHI (P < 0.05) were associated with having surgery. Eleven out of 28 (39.3%) surgical patients required respiratory support (oxygen or positive airway pressure) postoperatively. Longer % total sleep time S_pO₂ <90% during PSG (P < 0.05) and lower S_pO₂ nadir (P < 0.05) were associated with requiring airway support. No patients experienced mortality, reintubation, or hospital readmission following AT, with majority (71.4%) discharged 1 day post-operatively. Eleven (57.9%) of the 19 patients who had a postoperative PSG had residual OSA, defined as AHI >5 events/h, but there was a significant improvement in TAHI (P < 0.01).ConclusionOur findings confirm the need for postoperative observation in a controlled setting for patients with extreme OSA undergoing AT. Although at higher risk of needing respiratory support, those patients undergoing AT for extreme OSA did not require re-intubation post-operatively or suffer serious harm. Barring contraindications to AT, surgery may still be a first-line therapy for some children with extreme OSA.     

Prevalence of sleep apnea and daytime sleepiness in professional truck drivers

IntroductionThe prevalence of obstructive sleep apnea (OSA) among professional truck drivers has varied from 28 to 78% in previous studies. In this study we wanted to estimate the prevalence of OSA and OSA with both subjectively measured sleepiness and objectively measured ability to stay awake (ie obstructive sleep apnea syndrome, OSAS) among professional truck drivers in Finland.Subjects and methodsAltogether 2066 professional truck drivers received a structured questionnaire. 175 drivers had a clinical examination and sleep laboratory studies, which included respiratory polygraphy (RP) and maintenance of wakefulness test (MWT). Three groups were formed: 75 subjects with suspected sleep apnea, 75 healthy controls and a random sample of 25 subjects.Results1095 drivers answered the questionnaire. RP was performed on 172 drivers and 167 drivers participated in MWT. The mean age was 40.7 years and the mean BMI was 27.7 kgm⁻². The prevalence of sleep apnea in professional truck drivers using various criteria were: AHI ≥5: 40.1%, AHI≥ 15: 16.2% and, AHI≥ 30: 7.2%. The prevalence depended on clinical history. Prevalence of AHI≥5 varied between 20 and 56.9% and prevalence of AHI≥15 was 4.3–25%. Altogether 4.8% of subjects with AHI ≥15 had abnormally short sleep latency in MWT (<19.4 min).ConclusionsModerate sleep apnea is common among professional truck drivers but significant inability to stay awake, defined as MWT <19.4 min, is found in about one of twenty professional drivers.     

Predictors of CPAP adherence following stroke and transient ischemic attack

ObjectiveContinuous positive airway pressure (CPAP) has been shown to improve functional, motor and cognitive outcomes in post-stroke obstructive sleep apnea (OSA). However, rates of CPAP adherence are often low and factors impacting CPAP adherence remain under-explored. Our objective was to determine predictors of CPAP adherence in patients who had a stroke or transient ischemic attack (TIA).MethodsWe screened 313 stroke/TIA patients for OSA using in-hospital polysomnography or the ApneaLink home sleep apnea test. Potential predictors were recorded at baseline and adherence to CPAP was recorded during a six-month follow-up visit. Selected variables from our univariate analyses were included in multivariate regression models to determine predictors of CPAP adherence. For our logistic regression analyses, CPAP adherence (CPAP use of ≥4 h per night) was the dependent outcome variable. In our linear regression analyses, total CPAP use per week (recorded in hours) was the dependent outcome variable.ResultsEighty-eight patients (mean age 67.81 ± 13.09 years, 69.32% male, mean body mass index 27.93 ± 5.23 kg/m²) were diagnosed with OSA, prescribed CPAP, and assessed for adherence at a six-month follow-up visit. In these 88 patients, 46 (52.27%) were adherent with CPAP therapy. From our regression models, two significant predictors of CPAP adherence were identified: greater functional status (p = 0.04) and not endorsing daytime tiredness (p = 0.047) post-stroke/TIA.ConclusionPatients with greater functional capacity and those with less daytime fatigue demonstrated stronger adherence to CPAP therapy. Our findings may facilitate future treatment strategies for enhancing CPAP adherence in the vulnerable stroke/TIA population.     

Effect of continuous positive airway pressure on day/night rhythm of prothrombotic markers in obstructive sleep apnea

ObjectiveObstructive sleep apnea (OSA) has been associated with an increased risk of atherothrombotic events. A prothrombotic state might partially explain this link. This study investigated OSA patients’ day/night rhythm of several prothrombotic markers and their potential changes with therapeutic continuous positive airway pressure (CPAP).MethodsThe study included 51 OSA patients [apnea hypopnea index (AHI) ⩾10] and 24 non-OSA controls (AHI < 10). Of the 51 OSA patients, 25 were randomized to CPAP and 26 to placebo-CPAP. Twelve blood samples were collected over a 24 h period to measure prothrombotic markers. For the apneic patients these samples were collected before treatment and after 3 weeks of treatment with either CPAP or placebo-CPAP. Day/night variation in prothrombotic markers was examined using a cosinor analysis.ResultsCompared with controls, OSA patients showed lower mesor (mean) and amplitude (difference between maximum and minimum activity) of D-dimer. In unadjusted (but not in adjusted) analysis, patients showed higher mesor of plasminogen activator inhibitor-1 (p < 0.05 in all cases). No significant group differences were seen in mesor and amplitude for either soluble tissue factor or von Willebrand factor, or the acrophase (time of the peak) and periodic pattern for any prothrombotic markers. There were no significant differences in changes of periodic pattern and in day/night rhythm parameters of prothrombotic markers pre- to post-treatment between the CPAP and placebo condition.ConclusionsThere may be altered day/night rhythm of some prothrombotic markers in OSA patients compared with controls. CPAP treatment for 3 weeks did not affect day/night rhythm of prothrombotic markers in OSA patients differently from placebo-CPAP.     

Nocturnal heart rate variation in diabetic and non-diabetic patients with sleep apnea syndrome

ObjectivesHeart rate variability (HRV) analysis is used for the evaluation of autonomic function in the cardiovascular system. Decreased HRV is associated with disorders affecting the autonomous system such as diabetes mellitus (DM) and obstructive sleep apnea (OSA). Previous studies have shown an association between OSA and DM. However, the interrelationships of HRV with OSA and DM are not well known. The aim of this study was to assess nocturnal HRV in patients who suffered from OSA with and without DM.MethodsSixty patients with OSA (27 with DM and 33 non-DM) underwent polysomnography for eight hours starting at midnight. From electrocardiogram (ECG) recordings taken as a part of polysomnography, time-domain and frequency-domain HRV parameters were evaluated to compare patients with regard to nocturnal HRV components such as low frequency (LF) and high frequency (HF), apnea–hypopnea index (AHI) and sleep parameters.ResultsIn the non-DM group, a direct relationship was observed between AHI and HRV rather than very low frequency (VLF) and LF/HF variables. This relationship was just significant between AHI and standard deviation of five-min average of normal R–R intervals and adjacent R–R intervals differing by 0.50 ms over 24 h (p < 0.05). In the DM group, the correlation between AHI and HRV parameters except HF and waking frequency was direct and non-significant. Intergroup comparison showed a significant difference between groups regarding AHI and HRV-index, LF and VLF (p < 0.05).ConclusionsDM can affect HRV; however, this is not the case in OSA patients. This means that in the presence of OSA, the DM effect on HRV disappears.