Project description:Obstructive sleep apnea (OSA) is associated with sleep-stage- and respiratory-event-specific sensorimotor cortico-muscular disconnection. The modulation of phase-amplitude cross-frequency coupling (PACFC) may influence information processing throughout the brain. We investigated whether sleep-stage-specific PACFC is impaired at the sensorimotor areas in OSA patients. C3 and C4 electrode EEG polysomnography recordings of 170 participants were evaluated. Different frequency band combinations were used to compute CFC modulation index (MI) to assess if MI differs between OSA and non-significant OSA patients in distinct sleep stages. We tested if the CFC-MI could predict daytime sleepiness in OSA. Theta-gamma CFC-MI at cortical sensorimotor areas was significantly reduced during all sleep stages; the delta-alpha CFC-MI was significantly reduced during REM and N1 while increasing during N2 in patients with respiratory disturbance index (RDI) > 15/h compared to those with RDI ≤ 15/h. A sleep stage classification using MI values was achieved in both patient groups. Theta-gamma MI during N2 and N3 could predict RDI and Epworth Sleepiness Scale, while delta-alpha MI during REM predicted RDI. This increase in disconnection at the cortical sensorimotor areas with increasing respiratory distress during sleep supports a cortical motor dysfunction in OSA patients. The MI provides an objective marker to quantify subjective sleepiness and respiratory distress in OSA.
Project description:Excessive daytime sleepiness (EDS) is a symptom of obstructive sleep apnea (OSA) that resolves under treatment with continuous positive airway pressure (CPAP). In some patients, sleepiness persists despite CPAP treatment. We retrospectively analyzed data on subjective residual EDS, assessed as an Epworth Sleepiness Scale score (ESS) >10, in patients from the European Sleep Apnea Database (n = 4,853, mean age ± SD 54.8 ± 11.8 years, 26.1% females), at baseline and at the first visit (median follow-up: 5 months, interquartile range 3-13). An ESS > 10 occurred in 56% of patients at baseline and in 28.2% of patients at follow-up. Residual EDS was analyzed in 2,190 patients (age: 55.1 ± 12.0 years, 26.1% females) with sleep monitoring data (median follow-up: 3 months, interquartile range 1-15). Sleep studies during CPAP use were obtained in 58% of these patients; EDS was reported by 47.2% of patients at baseline and by 30.3% at follow-up. Residual OSA, defined as an apnea-hypopnea index >10/h, and insufficient CPAP adherence, defined as nightly use <4 h, occurred with similar frequency in patients with and without EDS at follow-up. Prevalence of residual EDS was highest (40%) in patients with a first follow-up visit at 0-3 months, then it was 13-19% in patients with a first follow-up visit after 4 months to 2 years. The change in ESS (n = 2,190) was weakly correlated with CPAP use (R2 = 0.023, p < 0.0001). Logistic regression showed that an ESS score >10 at the first follow-up visit was associated directly with ESS at baseline and inversely with duration of follow-up, and CPAP use (R2 of the model: 0.417). EDS showed heterogeneity in different European countries both at baseline and at the first follow-up visit, suggesting modulation by cultural and lifestyle factors. In conclusion, residual EDS in CPAP-treated OSA occurred in approximately one in four patients at follow-up; its prevalence was highest (40%) in the first 3 months of treatment and subsequently decreased. The finding of residual EDS in a significant percentage of optimally treated OSA patients suggests that wake-promoting agents may be useful, but their indication should be evaluated after at least 3 months of treatment.
Project description:PurposeTo investigate white matter (WM) structural alterations using diffusion tensor imaging (DTI) in obstructive sleep apnea (OSA) patients, with or without residual sleepiness, following adherent continuous positive airway pressure (CPAP) treatment. Possible quantitative relationships were explored between the DTI metrics and two clinical assessments of somnolence.Materials and methodsTwenty-nine male patients (30-55 years old) with a confirmed diagnosis of OSA were recruited. The patients were treated with CPAP therapy only. The Psychomotor Vigilance Task (PVT) and Epworth Sleepiness Scale (ESS) were performed after CPAP treatment and additionally administered at the time of the magnetic resonance imaging (MRI) scan. Based on the PVT results, the patients were divided into a nonsleepy group (lapses ≤5) and a sleepy group (lapses >5). DTI was performed at 3T, followed by an analysis using tract-based spatial statistics (TBSS) to investigate the differences in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (λ1 ), and radial diffusivity (λ23 ) between the two groups.ResultsA higher MD (P < 0.05) was observed in the sleepy group than the nonsleepy group in the whole-brain TBSS analysis in the WM. The increased MD (17.8% of the fiber tracts; P < 0.05) was caused primarily by an elevated λ23 . Axial diffusivity (λ1 ) exhibited no significant difference (P > 0.17). The alterations in FA or MD of individual fiber tracts occurred mainly in the internal/external capsule, corona radiata, corpus callosum, and sagittal stratum regions. The FA and MD values correlated with the PVT and ESS assessments from all patients (R ≥ 0.517, P < 0.05).ConclusionGlobal and regional WM alterations, as revealed by DTI, can be a possible mechanism to explain why OSA patients with high levels of CPAP use can have differing responses to treatment. Compromised myelin sheath, indicated by increased radial diffusivity, can be involved in the underlying WM changes. Evidence level: 1 J. MAGN. RESON. IMAGING 2017;45:1371-1378.
Project description:Objectives:Despite the fact that sleep disturbances have been associated with poor maternal and neonatal health outcomes in pregnancy, no studies have assessed excessive daytime sleepiness or the risk for sleep apnea among pregnant Saudi Arabian women. We sought to estimate the prevalence of excessive daytime sleepiness (EDS) and the high risk for sleep apnea (OSA) in a sample of pregnant Saudi women. Methods:An anonymous self-report questionnaire was completed by 517 pregnant women who attended obstetric outpatient clinics at King Abdulaziz Medical City, Riyadh, Saudi Arabia, for a routine pregnancy check. We collected demographic and clinical data for all patients and used the Berlin Questionnaire and the Epworth Sleepiness Scale to determine the primary outcomes. Results:A high risk of OSA was found in 37.1% of women (95% confidence interval (CI): 33.00%-41.50%), and EDS was found in 32.1% (95% CI: 28.10%-36.30%). The presence of both (EDS and a high risk of OSA) was found in 14.9% of women (95% CI: 11.90%-18.30%). We found increased odds of EDS in women who reported pain three times or more per week (adjusted odds ratio (aOR) = 2.59) and insomnia (aOR = 1.65). Older women (? 37 years) (aOR = 3.00), those who reported pain once a week (aOR = 1.99), pain twice a week (aOR = 2.75), three times or more a week (aOR = 2.57), and insomnia (aOR = 1.95) increased the odds of high risk for OSA. Conclusions:EDS and a high risk for OSA affected a large portion of the pregnant women included in the study, primarily those who reported pain and insomnia. Our study provides important information for gynecologists to help promote healthy sleep and manage the issues arising from sleep disturbances among pregnant women as part of their daily practice.
Project description:Many patients with obstructive sleep apnea (OSA) experience excessive daytime sleepiness (EDS), which can negatively affect daily functioning, cognition, mood, and other aspects of well-being. Although EDS can be reduced with primary OSA treatment, such as continuous positive airway pressure (CPAP) therapy, a significant proportion of patients continue to experience EDS despite receiving optimized therapy for OSA. This article reviews the pathophysiology and clinical evaluation and management of EDS in patients with OSA. The mechanisms underlying EDS in CPAP-treated patients remain unclear. Experimental risk factors include chronic intermittent hypoxia and sleep fragmentation, which lead to oxidative injury and changes in neurons and brain circuit connectedness involving noradrenergic and dopaminergic neurotransmission in wake-promoting regions of the brain. In addition, neuroimaging studies have shown alterations in the brain's white matter and gray matter in patients with OSA and EDS. Clinical management of EDS begins with ruling out other potential causes of EDS and evaluating its severity. Tools to evaluate EDS include objective and self-reported assessments of sleepiness, as well as cognitive assessments. Patients who experience residual EDS despite primary OSA therapy may benefit from wake-promoting pharmacotherapy. Agents that inhibit reuptake of dopamine or of dopamine and norepinephrine (modafinil/armodafinil and solriamfetol, respectively) have demonstrated efficacy in reducing EDS and improving quality of life in patients with OSA. Additional research is needed on the effects of wake-promoting treatments on cognition in these patients and to identify individual or disorder-specific responses.
Project description:PurposeObstructive sleep apnea (OSA) is underdiagnosed, partially from variable clinical presentations. Emphasis is often placed on Epworth Sleepiness Scale (ESS), a subjective measure of sleepiness, but variable in OSA. We hypothesized that daytime complaints measured with Language of Sleepiness Questionnaire (LOS) in OSA are not being captured by ESS.MethodsAdults referred to a tertiary sleep clinic undergoing sleep studies completed ESS and LOS questionnaires (20 items with various patient-reported descriptors). LOS was examined in patients who had or did not have OSA without sleepiness based on ESS < 10. Cluster analysis was performed to assess whether or not groups of individuals differed based on classification with or without OSA and with or without ESS-based sleepiness.ResultsApproximately half the study population (n = 185 completed) had OSA. ESS score (mean ± SD) was 9.0 ± 5.4. There was no significant difference in ESS between patients with and without OSA (9.0 ± 5.1 vs 9.1 ± 5.7, p = 0.969). In patients with OSA, females, older patients and white patients were significantly less likely to have an ESS ≥ 10 when compared to patients with an ESS < 10. In patients with an ESS < 10, there were no significant differences in descriptors of sleepiness between patients with and without OSA with the most common descriptors selected being "I lack energy," "I wake up sleepy," "I keep waking up," and "I don't sleep enough."ConclusionsThe ESS failed to discriminate patients with OSA from those without OSA. Despite an ESS < 10, both daytime and sleep complaints using the LOS questionnaire were present in patients with OSA. Asymptomatic OSA may be less common than previously reported.
Project description:INTRODUCTION:Sleepiness is the main clinical expression of obstructive sleep apnea (OSA) syndrome resulting from upper airway collapse. Recent studies have discussed the fact that the presence of T. gondii cysts in the brain and the resulting biochemical and immunological mechanisms could be linked to neurobehavioral disorders. The aim of the present study was to explore the potential impact of chronic toxoplasmosis on sleepiness and on obstructive sleep apnea (OSA) severity in OSA obese patients. MATERIALS AND METHODS:A case control study on obese patients screened for OSA was performed. According to the sleep disorder and matched based on gender, age and body mass index (BMI), two groups of obese patients were selected from our sample collection database. All patients were tested for toxoplasmosis serological status measuring anti-Toxoplasma IgG and IgM levels. Univariable and multivariable logistic regression models were performed to assess the impact of chronic toxoplasmosis on sleepiness and OSA severity. RESULTS:107 obese patients suffering from OSA were included in the study (median age: 53.3 years Interquartile range (IQR): [41.9-59.9]; median BMI: 39.4 kg/m2 IQR: [35.5-44.1], apnea-hypopnea index = 27.5 events/h [10.7-49.9]). Chronic toxoplasmosis was present in 63.4% and 70.7% of patients with or without sleepiness (p = 0.48), respectively and was not associated either to sleepiness (OR: 0.76, 95% CI: [0.52; 2.33], p = 0.64) or OSA severity (OR = 1.75, 95% CI: [0.51; 5.98] p = 0.37). CONCLUSION:Although chronic Toxoplasma infection in immunocompetent humans has been associated to several behavioral disorders or pathologies in recent literature, we demonstrate here that chronic toxoplasmosis is not associated to sleepiness and to sleep apnea syndrome severity in obese patients suspected of sleep apnea syndrome.
Project description:ObjectiveTo assess sleepiness, TNF-? plasma levels, and genomic variance in the TNF-? gene in children with obstructive sleep apnea (OSA).Study designChildren being evaluated for OSA (n = 60) and matched control children (n = 80) were assessed with a modified Epworth Sleepiness Scale questionnaire and underwent a blood draw the morning after nocturnal polysomnography. TNF-? plasma concentrations were assayed using ELISA, and genomic DNA was extracted. Genotyping and allelic frequencies were determined for 4 TNF-? single nucleotide polymorphisms using real-time polymerase chain reaction genotyping assays.ResultsMorning TNF-? levels and Epworth Sleepiness Scale scores were increased in the presence of OSA, but substantial variability was present. Although TNF-? plasma concentrations were globally increased in OSA, most of the variance was attributable to the presence or absence of TNF-? -308G gene polymorphism.ConclusionsTNF-? levels are increased in a subset of children with OSA, particularly among those harboring the TNF-? -308G single nucleotide polymorphism. Among the latter, significant increases in excessive daytime sleepiness symptoms are also present. The relatively high variability of excessive daytime sleepiness in pediatric OSA may be related to underlying TNF-? gene polymorphisms, particularly -308G.
Project description:Study Objectives:To determine whether defining two subtypes of sleep-disordered breathing (SDB) events-with or without hypoxia-results in measures that are more strongly associated with hypertension and sleepiness. Methods:A total of 1022 participants with 2112 nocturnal polysomnograms from the Wisconsin Sleep Cohort were analyzed with our automated algorithm, developed to detect breathing disturbances and desaturations. Breathing events were time-locked to desaturations, resulting in two indices-desaturating (hypoxia-breathing disturbance index [H-BDI]) and nondesaturating (nonhypoxia-breathing disturbance index [NH-BDI]) events-regardless of arousals. Measures of subjective (Epworth Sleepiness Scale) and objective (2981 multiple sleep latency tests from a subset of 865 participants) sleepiness were analyzed, in addition to clinically relevant clinicodemographic variables. Hypertension was defined as BP ? 140/90 or antihypertensive use. Results:H-BDI, but not NH-BDI, correlated strongly with SDB severity indices that included hypoxia (r ? 0.89, p ? .001 with 3% oxygen-desaturation index [ODI] and apnea hypopnea index with 4% desaturations). A doubling of desaturation-associated events was associated with hypertension prevalence, which was significant for ODI but not H-BDI (3% ODI OR = 1.06, 95% CI = 1.00-1.12, p < .05; H-BDI OR 1.04, 95% CI = 0.98-1.10) and daytime sleepiness (? = 0.20 Epworth Sleepiness Scale [ESS] score, p < .0001; ? = -0.20 minutes in MSL on multiple sleep latency test [MSLT], p < .01). Independently, nondesaturating event doubling was associated with more objective sleepiness (? = -0.52 minutes in MSL on MSLT, p < .001), but had less association with subjective sleepiness (? = 0.12 ESS score, p = .10). In longitudinal analyses, baseline nondesaturating events were associated with worsening of H-BDI over a 4-year follow-up, suggesting evolution in severity. Conclusions:In SDB, nondesaturating events are independently associated with objective daytime sleepiness, beyond the effect of desaturating events.