Obstructive Sleep Apnea Patients Research Articles

Incident Obstructive Sleep Apnea in Patients with Primary Aldosteronism following COVID-19 Infection

Incident Obstructive Sleep Apnea in Patients with Primary Aldosteronism following COVID-19 Infection

Precision medicine approaches in obstructive sleep apnoea: The role of dentist-sleep physician partnerships.

Obstructive Sleep Apnoea (OSA) is a common heterogenous sleep disorder that is associated with a wide range of comorbidities and consequences, including the development of neurocognitive and cardiometabolic disorders. The heterogeneity of OSA necessitates a precision medicine approach to accurately diagnose this condition and to effectively manage patients. One of the primary models of precision medicine is described by the P4 approach of predicting those who are susceptible to disease, preventing the occurrence of disease, personalizing treatment, and encouraging patients to participate in their individual healthcare journey. Recent advances in oral appliance therapy and OSA monitoring techniques have fostered an exciting opportunity for enhanced collaboration between dentists and sleep physicians to optimize OSA precision medicine care. This review aims to discuss the sources of heterogeneity among OSA patients, provide an overview of the growing applications of oral appliance therapy and tailored monitoring programs for OSA that are shifting treatment to a more personalized and participatory model of care, and outline the pivotal role of dentists in managing patients with OSA.

Obstructive Sleep Apnea in Patients with Difficult to Treat Asthma

Obstructive Sleep Apnea in Patients with Difficult to Treat Asthma

The Serum 25(OH) Vitamin D, Calcium, and Parathyroid Hormone Levels of The Patients With The Obstructive Sleep Apnea Syndrome

Background: Although there is evidence linking vitamin D to many neurochemical processes involved in sleep, the association between the obstructive sleep apnea and vitamin D, calcium and parathyroid hormone is still unknown, as clinical research have shown inconsistent findings. In this study, we aimed to examine the hypothesis that if there is any relationship between obstructive sleep apnea and serum vitamin D, calcium and parathyroid hormone levels in order to manage treatment. Methods: 56 patients (32 male, 24 female) admitted to the University of Health Sciences Adana City Training and Research Hospital otorhinolaryngology clinic between January 1st, 2022 and January 1st 2023 without any acute and chronic disease were included in the study. The range of participants was 18-70. In this study we examined the serum vitamin D, calcium and parathyroid hormone levels of 32 obstructive sleep apnea patients and compared their serum vitamin D, calcium and parathyroid hormone levels with the serum vitamin D, calcium and parathyroid hormone levels of 24 normal patients in the control group. Results: When the serum vitamin D, calcium and parathyroid hormone levels of obstructive sleep apnea patients and serum vitamin D, calcium and parathyroid hormone levels of normal patients were compared we did not find a statistically significant difference which may be due to our patient density. Conclusion: Vitamin D, calcium and parathyroid hormone levels are not likely related to the presence or absence of obstructive sleep apnea. More intervention studies are needed to better clarify the relation between the obstructive sleep apnea and vitamin D, calcium and parathyroid hormone.

Cortical activation during the verbal fluency task for obstructive sleep apnea patients with depressive symptoms: A multi-channel fNIRS study.

The aim of our study was to elucidate differences in brain activity patterns among obstructive sleep apnea (OSA) patients, OSA patients with depressive symptoms, and healthy controls (HCs). We also investigated the relationship between brain function and depression in OSA patients. A total of 95 subjects were included in the study, including 34 OSA patients without depressive symptoms, 31 OSA patients with depressive symptoms, and 30 HCs. The 53-channel functional near-infrared spectroscopy (fNIRS) was used to monitor the concentration of oxy-hemoglobin (Oxy-Hb) in the brain, whereas the participants performed the verbal fluency task, and the degree of depression was scored using the 17-item Hamilton Rating Scale for Depression (HAMD-17). Hierarchical regression models were conducted to analyze the association of fNIRS features with depressive symptom. The Oxy-Hb changes of the three groups were significantly different in Channels 25 (H=9.878, p=.007) and 43 (H=6.957, p=.031). Inter-group comparisons showed that the Oxy-Hb change of Channel 25 (located in the dorsolateral prefrontal cortex [DLPFC]) in OSA group was less than that in HC group (p=.006), and the Oxy-Hb change of Channel 43 (located in the right frontal polar region) in OSA group with depression was less than that in OSA group (p=.025). Spearman's test showed that there was a significant negative correlation between HAMD-17 scores and mean Oxy-Hb changes in Channel 43 (r=-.319, p<.05) in the OSA patients. Using hierarchical regression, Oxy-Hb changes in Channel 43 accounted for a significant proportion of the variation in outcome variables, even when accounting for other polysomnography features. Changes in the hemodynamic response of DLPFC may be a potential mechanism of executive dysfunction in OSA patients. And the right frontal polar region may be significant in assessing depressive symptoms in patients with OSA.

The Swedish sleep apnea registry (SESAR) cohort – “Real world data” on a national level

IntroductionThe Swedish Sleep Apnea Registry (SESAR) collects clinical data from individual obstructive sleep apnea (OSA) patients since 2010. SESAR has recently been integrated with additional national healthcare data. The current analysis presents the SESAR structure and representative clinical data of a national sleep apnea cohort. MethodsClinical data from unselected patients with a diagnosis of OSA are submitted to the SESAR registry. 48 sleep centers report data from diagnosis, treatment starts with Continuous Positive Airway Pressure (CPAP), oral devices (OD), and Upper Airway Surgery (UAS). Data from follow-up are included. SESAR is linked to mandatory national healthcare data (mortality, comorbidities, procedures, prescriptions) and diagnosis-specific quality registries (e.g. stroke, heart failure, diabetes) within the DISCOVERY project. Results83,404 OSA patients have been reported during the diagnostic workup (age 55.4 ± 14.1 years, BMI 30.8 ± 6.5 kg/m2, AHI 25.8 ± 21.6n/h, respectively). At least one cardiometabolic and respiratory comorbidity is recognized in 57 % of female and 53 % of male OSA patients with a linear increase across OSA severity. In 54,468, 7,797, and 390 patients, start of CPAP, OD or UAS treatment is reported, respectively. OD patients have 4 units lower BMI and 10 units lower AHI compared to patients started on CPAP. UAS patients are characterized by 10 years lower age. The degree of daytime sleepiness is comparable between treatment groups with mean Epworth Sleepiness Scale Scores between 9 and 10. ConclusionSESAR is introduced as a large national registry of OSA patients. SESAR provides a useful tool to highlight OSA management and to perform relevant outcome research.

The Relationship Between NLRP3 Inflammasome and Its Downstream Inflammatory Factors in Obstructive Sleep Apnea Patients with Carotid Atherosclerosis Under Cigarette Exposure

Aim: To study the relationship between NLRP3 (nucleotide oligomerization domain [NOD]-, leucine-rich repeats [LRR]-, and pyrin domain-containing protein 3) inflammasome and its downstream inflammatory factors in obstructive sleep apnea (OSA) patients with carotid atherosclerosis (CAS) under cigarette exposure, further exploring the risk factors of CAS in OSA patients. Methods: A total of 109 adult males who underwent polysomnography and carotid artery ultrasonography in our hospital from October 2019 to December 2021 were selected. According to the detection results, they were divided into the OSA group, the CAS group, and the OSA combined CAS group; additionally, 29 healthy subjects who underwent a physical examination were also included. According to whether they were smoking, the groups were further divided into smoking and non-smoking groups. The age, body mass index (BMI), blood pressure, apnea-hypopnea index (AHI), lowest blood oxygen saturation (LSaO2), carotid intima-media thickness (CIMT), levels of blood sugar, blood low-density lipoprotein cholesterol (LDLc), and serum NLRP3, interleukin-1β (IL-1β), and interleukin-18 (IL-18) of all subjects were recorded. Results: The OSA combined CAS group had higher LDLc levels and AHI and lower LSaO2 than the OSA group and CAS group. The levels of serum NLRP3, IL-1β, and IL-18 in the OSA group were higher than those in the normal control group (P &lt; 0.05); and those in the OSA combined CAS group were higher than the OSA group and CAS group (P &lt; 0.05), regardless of cigarette exposure. Considering cigarette exposure, serum NLRP3, IL-1β, and IL-18 levels were higher in the OSA, CAS, and OSA combined CAS smoking groups than those in the non-smoking group (P &lt; 0.05). Under cigarette exposure, AHI, LDLc, NLRP3, IL-1β, and IL-18 were significantly positively correlated (P &lt; 0.05), and LSaO2 was negatively correlated with CAS in OSA (P &lt; 0.05). AHI, LSaO2, LDLc, NLRP3, and IL-1β are the risk factors for OSA combined with CAS. Conclusion: LSaO2, AHI, LDLc, NLRP3, and IL-1β are the important risk factors for OSA combined with CAS under cigarette exposure, and their levels can be used to predict the occurrence of CAS in OSA.

Evaluation of obstructive sleep apnea in patients with metabolic syndrome

Evaluation of obstructive sleep apnea in patients with metabolic syndrome

Dentoskeletal changes of long-term oral appliance treatment in patients with obstructive sleep apnea: A systematic review and meta-analysis.

This systematic review and meta-analysis aimed to evaluate the dental and skeletal effects of the long-term oral appliance (OA) treatment in patients with obstructive sleep apnea (OSA) and provide insights for clinicians in treatment planning and decision-making for OSA patients undergoing OA treatment. A comprehensive literature search was conducted in major databases up to April 2024. Studies were included if they assessed long-term OA treatment (≥6 months) in adults with OSA using any type of mandibular advancement device (MADs) or tongue retaining device (TRD). Dental and skeletal changes, measured by dental cast and cephalometric analysis, were the primary outcomes. A total of 42 studies were included in the systematic review, with 23 included in the meta-analysis. Long-term OA treatment was associated with a significant decrease in overbite (0.87mm, 95% CI: 0.69-1.05) and overjet (0.86mm, 95% CI: 0.69-1.03). Subgroup analyses showed the decrease of overbite and overjet progressively changed over the years intervals. There was a significant retroclination of the upper incisors (U1-SN, 2.58°, 95% CI: 1.07-4.08) and proclination of the lower incisors (L1-MP, -2.67° (95% CI: -3.78-1.56). Skeletal changes were not significant. Overbite and overjet gradually decreased in the long-term OA treatment, which might predominantly result from the retroclination of the upper incisors and the proclination of the lower incisors. The skeletal patterns in the anteroposterior and vertical direction might remain relatively stable over time. There was a tendency for the clockwise rotation of the mandible.

Assessing Cognitive Impairments in Obstructive Sleep Apnea Patients Using Montreal Cognitive Assessment (MoCA) Scores.

Obstructive Sleep Apnea (OSA) is a chronic condition associated with cognitive impairment and various comorbidities. This prospective study evaluated cognitive deficits in OSA patients and identified clinical factors affecting cognitive function. Seventy-two participants were assessed using polysomnography (PSG) and the Montreal Cognitive Assessment (MoCA). Findings revealed significantly lower MoCA scores in severe OSA patients compared to those with mild or moderate OSA. Severe OSA patients had a median MoCA score of 23.5 (20.0-25.0), indicating more significant cognitive impairment, while those with normal OSA severity had the highest median score of 28.5 (27.8-29.2). Mild and moderate OSA patients had median scores of 26.5 (21.0-28.0) and 25.0 (23.80-26.0), respectively (p < 0.008). Logistic regression showed that ex-smoking status negatively impacted MoCA scores more in the unadjusted model (p = 0.003) than in the adjusted one (p = 0.018). Forced Vital Capacity (FVC) positively correlated with MoCA scores, stronger in the unadjusted model (p < 0.001 vs. p < 0.03). Higher Oxygen Desaturation Index (ODI) correlated with higher MoCA scores while increasing Apnea-Hypopnea Index (AHI) severity correlated with lower MoCA scores in both models. A significant negative correlation was found between age and MoCA score (r = -0.473, p < 0.001), and between MoCA score and AHI (r = -0.350, p < 0.003). This study highlights the need for sensitive cognitive screening tools like MoCA inevaluating OSA patients, linking cognitive impairment closely with OSA severity and other clinical factors.

Effect of exercise versus mandibular advancement device in moderate obstructive sleep apnea patients with mandibular retrognathia: A randomized clinical trial

ABSTRACT Objective The aim of this study was to investigate the effects of exercise and mandibular advancement device (MAD) on severity of Obstructive sleep apnea syndrome (OSAS) with mandibular retrognathia. Methods Patients were randomly allocated into either exercise group or MAD group. All patients underwent blood tests, polysomnography studies and questionnaires studies at enrollment and at the 12-week’s follow-up. Results Our study showed MAD was superior to exercise in improving polysomnographic outcomes and Snore Scale (SS) score. No significant difference was observed between the two treatments in terms of Epworth Sleepiness Scale (ESS) score. Moreover, in the exercise group, improvements were also observed in total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C). Conclusion MAD was more effective than exercise in improving sleep efficiency. Exercise can improve daytime sleepiness and lipid metabolism, independent of the effects on BMI. Trial registration ChiCTR2000034188

Tele-Pulmonary Rehabilitation and Mediterranean-like Lifestyle, Adjunctively to Continuous Positive Airway Pressure in Obstructive Sleep Apnea Patients: Effects in Fitness and Oxidative Indicators

Obstructive sleep apnea (OSA), often overlooked by clinicians, may lead to negative outcomes if left untreated. In this study, we examined the efficacy and efficiency of a 12-week unsupervised tele-rehabilitation program in OSA patients and focused on the potential changes in their fitness indicators and oxidative status. Forty OSA patients were allocated into two groups: the CPAPgroup (AHI 52.0 ± 31.5 events/h; age, 49.7 ± 9.4 years; BMI, 32.1 ± 7.6 kg/m2; control group) versus the non-CPAPgroup (AHI 38.2 ± 21.5 events/h; age, 49.3 ± 10.7 years; BMI, 32.3 ± 5.1 kg/m2; intervention group; personalized recommendations for nutrition—based on the Mediterranean diet—and exercise programs). Measurements included anthropometric characteristics and body composition through whole-body bioelectrical impedance analysis. In addition, participants underwent blood sampling for reactive oxygen metabolites’ levels (d-ROM), plasma antioxidant capacity (PAT), and Lipoprotein (a) (Lp(a)), as well as a 6 min walk test (6MWT). Statistically significant differences were detected in both groups (CPAPgroup versus non-CPAPgroup) after 12 weeks between Lp(a) (−32.2 ± 25.5%, p = 0.021 versus −17.7 ± 16.3%, p = 0.034) and 6MWT (16.6 ± 9.3%, p &lt; 0.001 versus 7.5 ± 6.6%, p = 0.002). ΔNRO2 (oxygen saturation difference between nadir during sleep and resting awake) was significantly associated with d-ROMs levels (p = 0.045), resting mean arterial pressure (p = 0.024), and chest circumference in maximal inhalation and exhalation (Δchest, p &lt; 0.001). To conclude, lifestyle interventions with unsupervised tele-exercise-rehabilitation pulmonary programs and Mediterranean-like diet may serve as adjunctive-to-CPAP therapeutic elements.

Knowledge and Attitude of General Dentists, Senior Dental Students, and Orthodontic Residents Toward Obstructive Sleep Apnea.

The main objective of this study was to compare the knowledge and attitude of general dentists, senior dental students, and orthodontic residents toward obstructive sleep apnea (OSA). A questionnaire was designed and administered among 73 senior dental students, 84 general dentists, and 50 orthodontic residents. The questionnaire asked for demographic information of the participants and assessed their knowledge and attitude toward OSA. The validity and reliability of the questionnaire were confirmed by experts. Data were analyzed by the Kruskal-Wallis and Bonferroni tests using SPSS (α = 0.05). The mean knowledge scores of general dentists and senior dental students were significantly lower than those of orthodontic residents (p < 0.001). However, there was no significant difference in the knowledge score of senior dental students and general dentists (p = 1). The mean knowledge score was significantly higher in dentists with 1-3 years of professional clinical experience (p = 0.02). The knowledge score was the highest in dentists working in private clinics followed by private offices and public clinics. The mean attitude score was the highest in orthodontic residents followed by general dentists and dental students. There was no significant difference in attitude based on the attended university, age, or time of graduation. According to the results, general dentists had insufficient knowledge about OSA, which could result in under-diagnosis or misdiagnosis of patients with OSA. This finding highlights the need for further education and training for dentists to properly identify and refer OSA patients to orthodontists or sleep specialists.

What can we do for obstructive sleep apnea patients in China?

AbstractObstructive sleep apnea (OSA) is a heterogeneous disease, having diversity in symptom, polysomnography parameter, etc. Studies have found that apnea–hypopnea index as a single measure cannot reflect its heterogeneity. More personalized diagnostic criteria and treatment measures are needed. But there are different kinds of results with different races and regions. It is essential to consider the characteristics of the local population when formulating individual treatment plan. There are significant discrepancies between Chinese and White race in terms of morphologic features, daily habits, religious beliefs and so on. However, the research based on the Chinese population still suffers from scarcity. This review sums up recent progress of studies on OSA from the Chinese population to provide useful references for related research and treatment in the future.

The Kir channel in the nucleus tractus solitarius integrates the chemosensory system with REM sleep executive machinery for homeostatic balance

The locus coeruleus (LC), nucleus tractus solitarius (NTS), and retrotrapezoid nucleus (RTN) are critical chemosensory regions in the brainstem. In the LC, acid-sensing ion channels and proton pumps serve as H+ sensors and facilitate the transition from non-rapid eye movement (NREM) to rapid eye movement (REM) sleep. Interestingly, the potassium inward rectifier (KIR) channels in the LC, NTS, and RTN also act as H+-sensors and are a primary target for improving sleep in obstructive sleep apnea and Rett syndrome patients. However, the role of Kir channels in NREM to REM sleep transition for H+ homeostasis is not known. Male Wistar rats were surgically prepared for chronic sleep–wake recording and drug delivery into the LC, NTS, and RTN. In different animal cohorts, microinjections of the Kir channel inhibitor, barium chloride (BaCl2), at concentrations of 1 mM (low dose) and 2 mM (high dose) in the LC and RTN significantly increased wakefulness and decreased NREM sleep. However, BaCl2 microinjection into the LC notably reduced REM sleep, whereas it didn’t change in the RTN-injected group. Interestingly, BaCl2 microinjections into the NTS significantly decreased wakefulness and increased the percent amount of NREM and REM sleep. Additionally, with the infusion of BaCl2 into the NTS, the mean REM sleep episode numbers significantly increased, but the length of the REM sleep episode didn’t change. These findings suggest that the Kir channels in the NTS, but not in the LC and RTN, modulate state transition from NREM to REM sleep.

Propofol-Dexmedetomidine versus Ketamine-Midazolam in Obstructive Sleep Apnea Patients undergoing Drug-Induced Sleep Endoscopy

Propofol-Dexmedetomidine versus Ketamine-Midazolam in Obstructive Sleep Apnea Patients undergoing Drug-Induced Sleep Endoscopy

The role of large muscle movements on excessive daytime sleepiness in patients with obstructive sleep apnea.

Obstructive sleep apnea (OSA) is a heterogeneous disorder requiring personalized diagnostic approaches. Restless sleep and excessive daytime sleepiness (EDS) frequently accompany OSA, and are mainly linked to sleep fragmentation secondary to apneas and/or hypopneas. In this study, we aimed to analyze the characteristics of LMMs in OSA and to evaluate interrelationship between LMMs and EDS. Untreated-naïve adult OSA patients, with vs. without EDS were prospectively enrolled. Patients with comorbid neurological/psychiatric diagnosis, usage of drugs/substances known to affect sleep and positive airway pressure therapy were excluded. Routine evaluation of video-polysomnography was followed by LMM scoring. LMMs were compared between OSA with vs. without EDS, and correlations of LMMs with ESS scores and macrostructural sleep parameters were analyzed. Sixty patients were included (median age 43.5 [37.0] years, %78.3 men); 17 had EDS with Epworth Sleepiness Scale (ESS) ≥ 10 (28.3%). Total LMM index in total sleep time (TST) was 7.9 [20.6]. Total LMM index in TST (p = 0.048) and N1 (p = 0.020), and arousal-related LMM index in TST (p = 0.050) and N1 (p = 0.026) were higher in OSA with EDS than those without EDS. ESS scores were positively correlated with total (r = 0.332,p = 0.028) and arousal-related (r = 0.338,p = 0.025) LMM indexes in N1, and abnormal respiratory event-related LMM indexes in N1 (r = 0.440,p = 0.003) and N3 (r = 0.293,p = 0.050) after correction for age, sex, body-mass-index and apnea-hypopnea index. Our study demonstrated that LMMs were more frequent in OSA with EDS than those without EDS. This may have broad implications for the mechanisms of motor restlessness and residual sleepiness in OSA and warrants larger-scale, long-term follow-up studies. No clinical trial registration due to the observational design of the study.

Obstructive Sleep Apnea in Metabolic Syndrome.

The metabolic syndrome (MetS), a cluster of cardiovascular risk factors, is associated with obstructive sleep apnea (OSA). OSA is a major contributor to cardiac, cerebrovascular, and metabolic disorders as well as to premature death. This cross-sectional study was done for 1 year in 103 patients of MetS diagnosed by the International Diabetes Federation criteria. All patients were subjected to the STOP-Bang questionnaire, and they were classified into low, intermediate, and high risks depending on the score. Patients falling in intermediate-high risk (score 3-8) were taken for overnight polysomnography to confirm the diagnosis of OSA (apnea-hypopnea index [AHI] ≥5) and were considered Group I. Patients with STOP-Bang score ≤2 or score ≥3 with AHI <5 were considered Group II (non-OSA). Out of 103 MetS patients enrolled in the study, only 70 (68.0%) were diagnosed with OSA, so the prevalence of OSA in MetS patients was 68%. The majority of the OSA cases had moderate-to-severe OSA (68.5%), and only 31.4% had mild OSA. The age of patients enrolled in the study ranged between 29 and 78 years, and the mean age of patients was 54.8 ± 9.4 years. Out of 103 MetS enrolled in the study, 59 (57.3%) were male and the rest were female, so the prevalence of severe OSA was higher in males than in females. The prevalence increases with an increase in age groups. Weight, body mass index (BMI), circumference, and waist circumference (WC) of cases of OSA were found to be significantly higher as compared to that of non-OSA. An incremental trend of increase in weight, BMI, neck circumference, and WC was observed with the increase in the severity of OSA. Patients of OSA as compared to non-OSA had significantly increased WC, blood pressure (BP), fasting, postprandial, random blood sugar, and triglyceride (TG) levels. A trend of increase in WC, BP fasting, postprandial, random blood sugar, and TG levels was associated with an increase in the severity of OSA. Snoring and daytime sleepiness were observed in a significantly higher proportion of OSA cases as compared to non-OSA cases. This study shows that OSA has a high prevalence in subjects with MetS. A high index of clinical suspicion is required for early diagnosis.

Maxillomandibular Advancement for Obstructive Sleep Apnea in Patients With Obesity: A Meta-Analysis.

To systematically review polysomnographic and cephalometric data in obstructive sleep apnea (OSA) patients with obesity (body mass index [BMI] ≥30 kg/m2) treated with maxillomandibular advancement (MMA). Scopus, PubMed, CINAHL, and The COCHRANE Library. A search was performed from inception until April 3, 2024, in each database. A total of 14 studies (143 subjects) were included. The mean age was 44.3 years (range: 17-69), 80.2% males (95% CI: 72.5-86.5), mean BMI of 35.3 (95% CI: 33.1-37.5), and mean duration to follow-up post-MMA was 13.7 months (95% CI: 10.1-17.3). All objective outcomes improved significantly; overall, apnea-hypopnea index (AHI) decreased by -57.3 ([95% CI: -71.5 to -43.2], p < 0.0001) lowest oxygen saturation (LSAT) increased by 14.1% ([95% CI: 9.9 to 18.3], p < 0.0001), and Epworth Sleepiness Scale (ESS) decreased by -9.4 ([95% CI: -13.5 to -5.2], p < 0.0001). Surgical cure was 39.2% (95% CI: 20.3-60.0), and surgical success was 85.6% (95% CI: 77.8-91.5). Comparing percent reduction in class 3 obesity (-92.9%) as compared to class 1 (-85.5%) and class 2 (-83.6%) exhibited a significant difference (1 vs 3 p = 0.0012, 2 vs 3 p = 0.015). Our findings suggest that MMA significantly improves subjective and objective outcomes in OSA amongst patients with obesity with results comparable to the overall population. Success rates remained above 80% in studies with the highest mean BMI. In addition, patients with class 3 obesity yielded a significantly increased benefit based on percent reduction in AHI compared with class 1 and 2. 1 Laryngoscope, 2024.

Effect of sleep-disordered breathing on stable electroencephalographic characteristics during night sleep in patients with arterial hypertension

Introduction. Obstructive sleep apnea (OSA) is the most common sleep-disordered breathing condition. A significant number of OSA patients often present with cardiovascular comorbidities, particularly arterial hypertension. OSA is associated with changes in bioelectrical activity of the brain, such as slowing of electroencephalographic activity in the cortex and reduced interhemispheric synchronization. These changes can become pathophysiological markers of sleep-disordered breathing.Aim. To investigate the effect of sleep-disordered breathing on a range of quantitative electroencephalogram (EEG) characteristics during nighttime sleep in patients with arterial hypertension and clinically significant OSA.Materials and methods. The material for this retrospective study consisted of 84 polysomnographic records of patients predominantly diagnosed with arterial hypertension. Patients were divided into three groups based on the apneahypopnea index (AHI). Polysomnographic records were used to assess the synchronization measure of brain electrical activity between occipital EEG leads. The synchronization measure was evaluated using a method based on wavelet bicoherence calculation.Results. Statistically significant differences were observed in the low-frequency ranges Δf1-Δf4: 0.2-1.0 Hz, 0.8-1.6 Hz, 1.0-2.0 Hz, 1.0-4.0 Hz. In these frequencies, the interhemispheric synchronization measure significantly decreased with increasing severity of apnea.Conclusion. To determine the severity of obstructive sleep apnea, a parameter based on the synchronization measure evaluated from symmetrical occipital EEG signals in the frequency ranges 0.2-1.0 Hz, 0.8-1.6 Hz, 1.0-2.0 Hz, and 1.0-4.0 Hz can be considered. This may serve as the basis for developing and implementing new diagnostic tools for assessing the severity of sleep-disordered breathing in practice.