• Sleep Medicine and Psychophysiology
• /
• v.23 no.2
• /
• pp.84-92
• /
• 2016

Objectives: The purpose of this study was to estimate the safety and efficacy of a mandibular advancement device (MAD), 'Bioguard,' for the treatment of obstructive sleep apnea (OSA). Methods: In this 5-week prospective, multi-center, single group, and non-inferiority trial, patients who chose 'Bioguard' as their treatment option were evaluated using both questionnaires (Pittsburgh Sleep Quality Index (PSQI), Epworth sleepiness scale (ESS)) and polysomonography (PSG) (apnea hypopnea index (AHI), oxygen saturation). All patient data, including clinical records, PSG studies (both pre- and post-treatment), and adverse events (AEs), were reviewed and analyzed. Results: Results were obtained for 59 of 62 patients (95.16%). No significant difference in success rate was found between the MAD treatment and surgical treatment (95% CI). AHI, PSQI, ESS and oxygen saturation demonstrated significant improvement (p < 0.001) after MAD treatment, and 39 of 62 patients (62.9%) reported 85 AEs. 79 of the 85 AEs (91.8%) were mild cases, and there were no severe AEs related to the MAD treatment. Conclusion: The MAD 'Bioguard' should be considered as an alternative treatment option for OSA patients.

• Sleep Medicine and Psychophysiology
• /
• v.24 no.2
• /
• pp.86-96
• /
• 2017

Objectives: This study aimed to analyze causality among sleep apnea, depression and cognitive function in patients with obstructive sleep apnea. Methods: We reviewed the medical records of 105 patients with sleep apnea and snoring who underwent overnight polysomnography (PSG). We analyzed various biological data, sleep variables (sleep duration and percentage) and respiratory variables [arousal index (AI), periodic leg movement index (PLM index), snoring Index (SI), mean SpO2, minimum SpO2, apnea-hypopnea index (AHI), and respiratory disturbance index (RDI)]. We also analyzed various data by sleep, cognition, and mood related scales: Pittsburgh sleep quality index (PSQI), Epworth sleepiness scale (ESS), snoring index by scale (SIS), Montreal Cognitive Assessment-Korean (Moca-K), Mini-mental State Examination-Korean (MMSE-K), clinical dementia rating (CDR), and Beck Depression Inventory (BDI). We analyzed causation among sleep, and respiratory, mood, and cognition related scales in obstructive sleep apnea patients. We analyzed the mediating effects of depression on sleep apnea patient cognition. Results: As Duration N1 increased and Total sleep time (TST) decreased, MOCA-K showed negative causality (p < 0.01). As BDI and supine RDI increased, causality was negatively related to MOCA-K (p < 0.01). As PSQI (p < 0.001) and SIS (p < 0.01) increased and as MMSE-K (p < 0.01) decreased, causality was positively related to BDI. BDI was found to mediate the effect of age on MOCA-K in patients with obstructive sleep apnea. Conclusion: Duration N1, total sleep time, BDI, and supine RDI were associated with cognitive function in obstructive sleep apnea patients. Depression measured by BDI partially mediated cognitive decline in obstructive sleep apnea patients.

• Sleep Medicine and Psychophysiology
• /
• v.8 no.1
• /
• pp.22-29
• /
• 2001

Objectives: Obstructive sleep apnea syndrome (OSA) is a moderately prevalent disorder. Even though much progress has been made in the diagnosis of this disorder, the cost-effectiveness of nocturnal polysomnography is undertermined and physicians and patients are still hesitant to undergo this procedure. The authors wanted to see the validity of chin press/tongue curl maneuver in estimating the severity of OSA which is easy to measure and was originally proposed by Simmons etc. by looking at the correlations between this score and the conventional respiratory disturbance indices. Methods: Forty-three sleep-related breathing disorder patients (28 OSA patients and 15 upper airway resistance syndrome (UARS) patients) who underwent investigation for posssible OSA were studied. Two conventional indices of OSA (apnea/hypopnea index (AHI) and oxygen saturation dip rate (SaO2 dips)), four other sleep variables (lowest SaO2, % of time with SaO2<90% (%SaO2 <90), % of sleep stage 1, mean length of SaO2 dips) and the score of Epworth sleepiness scale (ESS) were compared with the chin press score (CPS) which was newly revised by the author and ranges from 0 to 6. Results: The age of subjects was $45.95{\pm}12.47$ (range 14-76) and their average BMI was $25.98{\pm}3.61$ (range 19.65-37.64). There were no significant differences in age, sex and BMI except repiratory disturbance indices and ESS (p<0.05) between OSA and UARS group. Grouped median CPS of the all subjects was 4.14 (range 1-6). There was a remarkable relationship between CPS and diagnosis category (Likelihood Ratio $X^2$ test; $X^2$=17.41, df=5, p=0.004) and measures of association (Somers' $d=0.65{\pm}0.12$, t=4.83, p=0.000) indicated that CPS increased when the diagnosis changed from UARS to OSA. Spearman's rank correlations between CPS and SaO2 dips (R=0.83), between CPS and AHI (R=0.77) were good (p<0.001). Other variables except mean length of SaO2 dips showed good correlations with CPS as well (p<0.05). Regression analysis indicated that when CPS is 3 there is a provability of 0.35 to have AHI of less than 5. Conclusion: Chin press scores that can be measured easily is well correlation with the conventional sleep apnea indices. They may therefore provide a useful guide in diagnosing obstructive sleep apnea synrome.

• Sleep Medicine and Psychophysiology
• /
• v.2 no.1
• /
• pp.55-64
• /
• 1995

During sleep, relatively major respiratory physiological changes occur in healthy subjects. The contributions and interactions of voluntary and metabolic breathing control systems during waking and sleep are quite different Alterations of ventilatory control occur in chemosensitivity, response to mechanical loads, and stability of ventilation. The activities of intercostal muscles and muscles involved in regulating upper airway size are decreased during sleep. These respiratory physiological changes during sleep compromise the nocturnal ventilatory function, and sleep is an important physiological cause of the nocturnal alveolar hypoventilation. There are several causes of chronic alveolar hypoventilation including cardiopulmonary, neuromuscular diseases. Obstructive sleep apnea syndrome (OSAS) is an important cause of nocturnal hypoventilation and hypoxia. Coexistent cardiopulmonary or neuromuscular disease in patients with OSAS contributes to the development of diurnal alveolar hypoventilation, diurnal hypoxia and hypercapnia. The existing data indicates that nocturnal recurrent hypoxia and fragmentation of sleep in patients with OSAS contributes to the development of systemic hypertension and cardiac bradytachyarrhythmia, and diurnal pulmonary hypertension and cor pulmonale in patients with OSAS is usually present in patients with coexisting cardiac or pulmonary disease. Recent studies reported that untreated patients with OSAS had high long-term mortality rates, cardiovascular complications of OSAS had a major effect on mortality, and effective management of OSAS significantly decreased mortality.

• Tuberculosis and Respiratory Diseases
• /
• v.49 no.6
• /
• pp.715-723
• /
• 2000

Background : Obstructive sleep apnea syndrome (OSAS) affects systemic blood pressure and cardiac function. The development of cardiovascular dysfunction including the changes of systemic blood pressure and cardiac rhythm, suggests that recurrent hypoxia and arousals from sleep may increase a sympathetic nervous system activity. Continuous positive airway pressure (CPAP) therapy has been found to be an effective treatment of OSAS. However, only a few studies have investigated the cardiovascular and sympathetic effects of CPAP therapy. We evaluated influences of nasal CPAP therapy on the cardiovascular system and the sympathetic activity in patients with OSAS. Methods : Thirteen patients with OSAS underwent CPAP therapy and were monitored using polysomnography, blood pressure, heart rate, presence of arrhythmia and the concentration of plasma catecholamines, before and with CPAP therapy. Results: The apnea-hypopnea index (AHI) was significant1y decreased (p<0.01) and the lowest arterial oxygen saturation level was elevated significantly after applying CPAP (p<0.01). Systolic blood pressure tended to decrease after CPAP but without statistical significance. Heart rates during sleep were not significantly different after CPAP. However, the frequency and number of types of arrhythmia decreased and sinus bradytachyarrhythmia disappeared after CPAP. Although there was no significant difference in the level of plasma epinephrine concentration, plasma norepinephrine concentration significantly decreased after CPAP (p<0.05). Conclusion : CPAP therapy decreased the apnea-hypopnea index, hypoxic episodes and plasma norepinephrine concentration. In addition, it decreased the incidence of arrhythmia and tended to decrease the systemic blood pressure. These results indicate that CPAP may play an important role in the prevention of cardiovascular complications in patients with OSAS.

• Sleep Medicine and Psychophysiology
• /
• v.18 no.2
• /
• pp.76-81
• /
• 2011

Objectives: This study aims to analyze the association between the severity of sleep apnea, sleep and mood related scales, and activity during sleep in obstructive sleep apnea syndrome (OSAS) patients. Methods: 176 drug-free male patients confirmed as OSAS (average age=$43{\pm}11$ years) were selected through nocturnal polysomnography (NPSG). OSAS was diagnosed with apnea-hypopnea index (AHI) >5, mean AHI was $39.6{\pm}26.0$. Sleep related scales were Stanford Sleepiness Scale (SSS), Epworth Sleepiness Scale (ESS), Pittsburg Sleep Quality Index (PSQI) and Morningness-Eveningness Scale (MES). Mood related scales were Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), State-Trait Anxiety Inventory (STAI) I, II and Profile of Mood States (POMS). NPSG was performed overnight with both wrist actigraphy (WATG). Parameters produced from WATG were total activity score, mean activity score and fragmentation index. We analyzed the correlation between each scale, AHI scored from NPSG and activity score analyzed from WATG. Results: ESS showed significant positive correlation with PSQI, BDI, BAI and STAI I, II, respectively (p<0.01). SSS showed significant positive correlation with PSQI and BAI (p<0.05, p<0.01). BAI showed significant positive correlation with total activity score, mean activity score and fragmentation index (p<0.05, p<0.01, p<0.05).Total activity score showed significant positive correlation with ESS and BAI, respectively (p<0.05). Fragmentation index showed significant positive correlation with ESS, PSQI and BAI (p<0.05, p<0.01, p<0.05). AHI, indicator of sleep apnea is showed no significant correlation with each sleep and mood related scale. Conclusion: The degree of daytime sleepiness tends to be associated with night sleep satisfaction, depression and anxiety, and the activity during sleep rather than the severity of sleep apnea.

• Sleep Medicine and Psychophysiology
• /
• v.24 no.2
• /
• pp.118-123
• /
• 2017

Central sleep apnea (CSA) is a highly prevalent comorbidity in patients with heart failure and may present in 25 to 40 percent of heart failure patients. Continuous positive airway pressure (CPAP) is the primary therapeutic option and effective in treatment of obstructive sleep apnea (OSA). In heart failure patients with CSA, several trials of CPAP showed a number of positive effects in heart failure treatment. A 58-year-old male visited the hospital because of dyspnea and he was diagnosed as heart failure with ischemic heart disease. He underwent coronary angiography and received percutaneous coronary intervention due to stenosis at the middle of left anterior descending coronary artery. However, dyspnea was not completely improved after treatment with percutaneous coronary intervention. The patient also experienced snoring and sleep apnea which worsened with symptom of dyspnea in the recent year. We suspected CSA and the patient underwent polysomnography to confirm whether sleep apnea was present. During the polysomnography, CSA with Cheyne-Stokes respiration (CSR) was observed and apnea-hypopnea index was 45.9/hr. The patient was treated with CPAP. After CPAP treatment, hypoxemia and CSA were resolved and dyspnea was improved with reducing NYHA class. We report a case successfully treated with clinical improvement by presuming CSA in a patient with heart failure.

• Sleep Medicine and Psychophysiology
• /
• v.11 no.1
• /
• pp.5-9
• /
• 2004

Obstructive sleep apnea (OSA) is a common disorder characterized by recurrent cessation of breathing due to complete or partial upper airway occlusion during sleep. The incompetent tone of palatal, pharngeal, and glossal muscles which fail to maintain airway patency during sleep causes narrowing of the airway dimension and increased resistance of breathing. The identification of the sites of upper airway obstruction in patients with OSA is important in understanding the pathogenesis and deciding the treatment modality of snoring and/or OSA. Various upper airway imaging modalities have been used to assess upper airway size and precise localization of the sites of upper airway obstruction during sleep. Dynamic imaging modalities enabled assessment of dimensional changes in the upper airway during respiration and sleep. This article focused on reviews of various upper airway imaging modalities, especially dynamic upper airway imaging studies providing important information on the pathogenesis of OSA.

• Sleep Medicine and Psychophysiology
• /
• v.3 no.2
• /
• pp.97-107
• /
• 1996

• Sleep Medicine and Psychophysiology
• /
• v.20 no.1
• /
• pp.31-34
• /
• 2013

Objectives: The aim of this study was to evaluate the differences in patients with positional dependent sleep apnea according to their non-supine apnea-hypopnea index (AHI, ${\geq}5$ vs. <5). Methods: 92 patients with positional sleep apnea were evaluated. The patients were divided into two groups : group I was non-supine AHI having ${\geq}5$ ; group II was non-supine AHI having less than 5. Statistical analysis was performed to find the difference between two groups. Results: In 92 patients, the number of group I patients was 11 (12%) and the number of group II patients was 81 (88%). In the severe AHI group, percentage of group I was dominated (70%) and showing a significant difference compared with the mild and moderate AHI groups (p<.05). In the severe body mass index (BMI) group, percentage of group I was dominated (54.5%) and showing a significant difference compared with of the mild and moderate BMI groups (p<.05). The percentage of group I was significantly higher than group II (p<.05) in the AHI, supine AHI, non-supine AHI and snore time. Conclusions: In patients with positional sleep apnea, severe OSA and high BMI are more common in patients with non-supine AHI${\geq}5$ than non-supine AHI<5.