Both the Duration of Apnea and the Number of Apneas Are Important in Obstructive Sleep Apnea Syndrome

조재훈 대한수면학회 2020 sleep medicine research Vol.11 No.2

Apnea and hypopnea are generally considered to be equivalent in calculating the apnea-hypopnea index (AHI) regardless of their kind and duration. However, we supposed that apnea and hypopnea could differ in their effects on arousal and oxygen desaturation, and that the duration of an occurrence of apnea or hypopnea could also be important. The following were analyzed for 182 cases of polysomnography in obstructive sleep apnea (OSA) patients. 1) We calculated the correlations between variables, such as AHI, arousal index, oxygen desaturation index (ODI), apnea index (AI), hypopnea index (HI), and mean apnea duration, using common statistical procedures. 2) We compared AHI, arousal index, and ODI in patients divided into short and long mean apnea-duration groups. We found that 1) AHI, arousal index, ODI, mean apnea duration, and AI were highly correlated with each other, but HI was not; and 2) arousal index and ODI were higher in the long mean apnea-duration group than in the short mean apnea-duration group. Hence apnea is more important for arousal and oxygen desaturation during sleep than is hypopnea. Longer apnea duration is associated with both more severe OSA and greater arousal and oxygen desaturation.

한국인 폐쇄수면무호흡 환자에서 수면무호흡두통

김정민,김정수,김종근,최재갑,이호원 대한신경과학회 2017 대한신경과학회지 Vol.35 No.1

Background: The prevalence of sleep apnea headache has not been established and its possible mechanism is unclear. This study evaluated the frequency of sleep apnea headache in Korean patients with obstructive sleep apnea (OSA) with the aim of identifying their clinical characteristics as well as the sleep parameters that are correlated with headache intensity. Methods: Between January 2005 and December 2014, 2000 patients who were referred to our sleep clinic underwent overnight polysomnography and were interviewed by a neurologist. The neurologist also reviewed the medical records and headache questionnaires of 1659 patients with OSA. We selected patients with sleep apnea headache based on diagnostic criteria of the International Classification of Headache Disorders (III beta version). Descriptive statistics were applied to analyze clinical characteristics and various sleep parameters. Pearson’s correlation coefficient and single/multivariate linear regression analysis were used to identify predictors of headache intensity. Results: Sleep apnea headache was diagnosed in 139 (8.4%) of the patients in this single-center study. The diagnosed patients had male dominancy (87.8%), severe sleep apnea (mean apnea-hypopnea index [AHI]>30), and were middle-aged (mean of 43.5 years old). The ratio of the apnea-hypopnea time to the total sleep time, AHI, the oxygen desaturation index, and the arousal index were positively correlated with headache intensity. AHI was the best predictor of headache intensity in the patients with sleep apnea headache. Conclusions: The frequency of sleep apnea headache among the Korean patients in this study was lower than in previous studies. We found that there was a strong positive correlation between OSA severity (mostly, AHI) and headache intensity in patients with sleep apnea headache.

마취한 개에서 비폐쇄성 무호흡이 혈역학적 변화에 미치는 영향

김진우(Jin Woo Kim),이상학(Sang Haak Lee),최영미(Young Mee Choi),권순석(Soon Seog Kwon),김영균(Young Kyoon Kim),김관형(Kwan Hyoung Kim),송정섭(Jeong Sup Song),박성학(Sung Hak Park),문화식(Hwa Sik Moon) 대한내과학회 2001 대한내과학회지 Vol.60 No.1

Background : The cardiovascular dysfunction frequently accompanies sleep apnea syndrome, but the exact pathophysiology of cardiovascular dysfunction still remains uncertain. Moreover, most studies are concerned with obstructive sleep apnea syndrome and the studies of central sleep apnea syndrome are rare. Methods : We studied with sixteen dogs which were anesthetized with intravenous pancuronium bromide. We created nonobstructive breath hold (apnea) in anesthetized dogs by means of alternating fixed duration (30s) of apnea and mechanical ventilation (breathing). After five or seven repetitions of this apnea-breathing cycle, we measured arterial oxygen pressure, arterial carbon dioxide pressure, heart rate, cardiac output, mean femoral artery pressure and mean pulmonary artery pressure separately before apnea (baseline), 25s after apnea (apneic period), 10s (early phase of postapneic period) and 25s (late phase of postapneic period) after resumption of breathing. We analysed the impact of oxygen trial on the hemodynamic changes by comparing measures of the eight 30% oxygen breathing dogs with the other eight room air breathing dogs. Results : Heart rate decreased significantly at apneic period compared to baseline (p<0.05), and increased significantly at early and late phase of postapneic period compared to apneic period (p<0.05). After oxygen trial, this change of heart rate showed significant difference (p<0.05). Cardiac output only tended to decrease during late phase of postapneic period by comparison with baseline and apneic period. Mean femoral artery pressure of apneic period increased more than that of baseline (p<0.05), and persisted until late phase of postapneic period (p<0.05). When oxygen was supplied, this change of increase disappeared, but did not show statistical significance. Mean pulmonary artery pressure did not change according to apnea-breathing cycle and oxygen trial. Conclusion : In anesthetized dogs with periodic nonobstructive apnea, the changes of heart rate, cardiac output, mean femoral artery pressure were noted and the change of heart rate was closely related with hypoxia. Through this study, indirectly, we were able to understand partially the changes of cardiovascular function in patients with central sleep apnea syndrome.(Korean J Med 60:61-69, 2001)

Prevalence and Public Awareness of Sleep Apnea Syndrome in South Korea

김근태,박혜리,조재욱,김지현,한수현,문혜진,이서영,조용원 대한수면연구학회 2022 Journal of sleep medicine Vol.19 No.3

Objectives: In South Korea, a significant number of patients with obstructive sleep apnea have benefited from the insured continuous positive pressure for sleep apnea as of 2018. However, there is limited information on public awareness of sleep apnea syndrome in the country. A nationwide survey was conducted to evaluate the current status of public awareness on the diagnosis and treatment of sleep apnea. Methods: We conducted an online survey using structured questionnaires on symptoms and knowledge of diagnosis and treatment modalities for sleep apnea. A total of 4,000 participants aged 21 to 69 were proportionally allocated according to the residential area, gender, and age group. Results: The STOP questionnaire, a screening tool for sleep apnea, revealed that 1,044 (21.6%) scored ≥2 points, 327 (8.1%) scored ≥3 points, and 64 (1.6%) scored 4 points. However, only 19 of the 1,044 patients were being treated for sleep apnea, and 13 had been using continuous positive airway pressure. For the diagnosis of sleep apnea, 1,318 participants (33.0%) responded that polysomnography was necessary. For sleep apnea treatment, 1,954 (48.9%) participants responded that lifestyle modification was the treatment of choice, while 1,036 (25.9%) chose continuous positive pressure. Conclusions: Although one-fifth were at high risk for sleep apnea, this disorder is still underestimated. Therefore, publicity and support are needed to improve public awareness of sleep apnea.

수면무호흡증이 혈압에 미치는 영향

이희상,이성훈,조현상,남궁기,한승진,방승규 大韓神經精神醫學會 1997 신경정신의학 Vol.36 No.1

본 연구에서는 수면무호흡증이 혈압에 미치는 영향을 살펴보고자 하였다. 연구대상은 1995년 1월1일부터 1995년 10월 31일까지 코골기와 수면무호흡 증상으로 인해 연정 뇌기능 수면 연구소에 수면다원검사가 의뢰된 140명의 환자를 대상으로 하였으며 그 중에서 원발성 고혈압을 제외한 심혈관계 질환이 있거나 항고혈압제를 복용하고 있는 환자, 그리고 자료가 불충분하거나 수면무호흡증으로 진단되지 않은 24명을 제외하고 나머지 116명을 최종분석 대상으로 하였다. 이들 대상 환자들로부터 얻은 자료를 수면변수와 호흡변수로 나누어 혈압과의 관계를 Pearson 상관관계와 다중회귀분석을 통해 다음과 같은 결과를 얻었다. 1) 평균 수축기 및 확장기 혈압과 유의한 상관관계가 있는 변수는 수면무호흡의 총시간 및 총횟수, 총수면시간중 평균 혈중산소포화도, 무호흡지수, 중추성 수면무호흡의 총시간 및 횟수, 폐쇄성 수면무호흡의 총시간등 이었다. 2) 다중회귀분석 결과 평균 수축기 및 확장기 혈압에 유의한 영향을 미치는 것으로 나타난 변인은 수면무호흡의 총시간이었으며 이것이 평균 수축기 및 확장기 혈압에 미치는 영향의 도는 각각 7.9%와 6.2%였다. 이상의 결과로 볼 때, 수면무호흡증이 혈압에 미치는 영향은 적은 것으로 나타났으며 무호흡의 유형에 관계없이 수면무호흡의 총시간만이 혈압에 영향을 주는 것으로 나타났다. 그리고 중추성 수면무호흡의 경우 평균 혈중 산소포화도의 감소, 각성에 따른 교감신경계 활성도의 증가이외에도 다른 기전에 의해 혈압 상승이 나타날 가능성이 있을 것으로 생각된다. Objects : This study was conducted to investigate the effects of sleep apnea syndromes on th systemic blood pressure. Methods : The subjects were 140 patients who were consulted to Yon-jung brain function and sleep research center for polysomnography due to snoring and sleep apnea from Jan. 1st 1995 to Oct. 31st 1995. Twenty-four out of 140 were excluded due to cardiovascular diseases other than systemic hypertension, antihypertensive medication, inadequate data or diagnosis other than sleep apnea syndrome. The remaining 116 were accepted as proper subjects. Using Pearson's correlation and multiple regression analysis, we looked for the relationship between sleep and respiratory variables to systemic blood pressure. Results : The results were as follows : 1) According to the correlation analysis, statistically significant variables to mean systolic and diastolic blood pressure were the total time and total number of sleep apnea, degree of oxygen saturation of total sleep time, apnea index, total time and total number of central apnea, and the total time of obstructive apnea. 2) According to the multiple regression analysis, only the total time of sleep apnea significantly affected mean systolic and diastolic blood pressure, and the degrees of affection were 7.9% and 6.2% respectively. Conclusion : these findings showed that sleep apnea syndrome had lower influence over systemic blood pressure than expected and regardless of the type, only the total time of sleep apnea influenced systemic blood pressure. In the case of central apnea, mechanisms other than hypoxemia and the increase of sympathetic activity during arousal may make it possible to increase systemic blood pressure.

Prevalence of Self-Perceived Snoring and Apnea and Their Association with Daytime Sleepiness in Korean High School Students

양광익,김지현,황보영,구대림,김대영,황경진,홍승봉 대한신경과학회 2017 Journal of Clinical Neurology Vol.13 No.3

Background and Purpose There has been no nationwide population-based study of the prevalence of self-perceived snoring/apnea in Korean adolescents. The purpose of this study was to estimate prevalence of self-perceived snoring/apnea in Korean high-school students and to evaluate their association with daytime sleepiness. Methods An online survey was used to investigate 12,672 students at 75 high schools across the 15 nationwide districts of South Korea. The variables were obtained using a self-reported questionnaire. The students answered questions about self-perceived snoring/apnea during the past 30 days. Daytime sleepiness was measured using a validated Korean version of the Epworth Sleepiness Scale, which was modified for adolescents. Covariates were the sex, school grade, frequency of self-perceived snoring/apnea, body mass index, sleep duration during a school day, and subjective perception of sleep duration. Results The prevalence of self-perceived snoring/apnea was 22.8% (26.4% for males vs. 18.8% for females, p<0.001) and 9.2% (10.5% for males vs. 7.7% for females, p<0.001). Obesity was significantly associated with self-perceived snoring [odds ratio (OR)=2.18, 95% confidence interval (CI)=1.94–2.46] and apnea (OR=1.57, 95% CI=1.33–1.86). Multivariate analysis showed that any frequency of self-perceived snoring/apnea was significantly associated with excessive daytime sleepiness (EDS). The OR of EDS increased significantly with the frequency of snoring and apnea. Female, sleep duration of <5 hours during a school day, and subjective perceptions of insufficient and considerable sleep durations were also significantly associated with EDS. Conclusions The prevalence of self-perceived snoring/apnea was significantly higher in students who were male and obese. Students with self-perceived snoring/apnea exhibited more significant EDS and an increased risk of EDS as the frequency of snoring and apnea increased.

A Classifying Model of Obstructive Sleep Apnea Based on Heart Rate Variability in a Large Korean Population

Park Pona,Kim Jeong-Whun 대한의학회 2023 Journal of Korean medical science Vol.38 No.7

Background: The majority of patients with obstructive sleep apnea do not receive timely diagnosis and treatment because of the complexity of a diagnostic test. We aimed to predict obstructive sleep apnea based on heart rate variability, body mass index, and demographic characteristics in a large Korean population. Methods: Models of binary classification for predicting obstructive sleep apnea severity were constructed using 14 features including 11 heart rate variability variables, age, sex, and body mass index. Binary classification was conducted separately using apnea-hypopnea index thresholds of 5, 15, and 30. Sixty percent of the participants were randomly allocated to training and validation sets while the other forty percent were designated as the test set. Classifying models were developed and validated with 10-fold cross-validation using logistic regression, random forest, support vector machine, and multilayer perceptron algorithms. Results: A total of 792 (651 men and 141 women) subjects were included. The mean age, body mass index, and apnea-hypopnea index score were 55.1 years, 25.9 kg/m2 , and 22.9, respectively. The sensitivity of the best performing algorithm was 73.6%, 70.7%, and 78.4% when the apnea-hypopnea index threshold criterion was 5, 10, and 15, respectively. The prediction performances of the best classifiers at apnea-hypopnea indices of 5, 15, and 30 were as follows: accuracy, 72.2%, 70.0%, and 70.3%; specificity, 64.6%, 69.2%, and 67.9%; area under the receiver operating characteristic curve, 77.2%, 73.5%, and 80.1%, respectively. Overall, the logistic regression model using the apnea-hypopnea index criterion of 30 showed the best classifying performance among all models. Conclusion: Obstructive sleep apnea was fairly predicted by using heart rate variability, body mass index, and demographic characteristics in a large Korean population. Prescreening and continuous treatment monitoring of obstructive sleep apnea may be possible simply by measuring heart rate variability.

폐쇄성 수면무호흡증의 발병기전

정유삼 대한비과학회 2009 Journal of rhinology Vol.16 No.2

Obstructive sleep apnea has a close relationship with the anatomical characteristics of the upper airway. But we should consider that obstructive sleep apnea always occurs only when the patients are asleep. Diminishing of neural signal to pharyngeal dilator muscles during the sleep state has a great role in the pathogenesis of obstructive sleep apnea. Narrowing of the upper airway could be due to aging, abnormality of craniofacial skeleton, obesity, narrowing of nasal cavity, adhesive force of mucosa, gravity, sleep, vibratory trauma of upper airway when snoring, compliance of pharyngeal dilator muscle, and apnea threshold according to blood carbon dioxide concentration. Understanding of these possible causes may help to develop treatment modality for obstructive sleep apnea and to introduce individual treatment. Obstructive sleep apnea has a close relationship with the anatomical characteristics of the upper airway. But we should consider that obstructive sleep apnea always occurs only when the patients are asleep. Diminishing of neural signal to pharyngeal dilator muscles during the sleep state has a great role in the pathogenesis of obstructive sleep apnea. Narrowing of the upper airway could be due to aging, abnormality of craniofacial skeleton, obesity, narrowing of nasal cavity, adhesive force of mucosa, gravity, sleep, vibratory trauma of upper airway when snoring, compliance of pharyngeal dilator muscle, and apnea threshold according to blood carbon dioxide concentration. Understanding of these possible causes may help to develop treatment modality for obstructive sleep apnea and to introduce individual treatment.

코골이가 수면무호흡증의 중증도를 예측할 수 있을까?

김시은,박봉수,박시형,신경진,하삼열,박진세,박강민,Kim, Si Eun,Park, Bong Soo,Park, Si Hyung,Shin, Kyong Jin,Ha, Sam Yeol,Park, Jin Se,Park, Kang Min The Korean Society of Clinical Neurophysiology 2015 Annals of Clinical Neurophysiology Vol.17 No.2

Background: The aim of this study was to investigate the predictive value of snoring frequency in the diagnosis and severity of obstructive sleep apnea. Methods: Patients who underwent polysomnography with one or more of the following characteristics were included: 1) sleepiness, non-restorative sleep, fatigue, or insomnia symptoms; 2) arousal due to cessation of breathing or the occurrence of gasping or choking when waking up; and 3) habitual snoring, breathing interruptions, or both, noted by a bed partner or other observer. We analyzed the differences in clinical and polysomnographic variables between patients with and without obstructive sleep apnea and investigated the associations of those variables with obstructive sleep apnea severity. Results: One hundred ninety-three patients met the inclusion criteria, and 145 of the 193 patients were diagnosed with obstructive sleep apnea. Multiple logistic regression analysis showed that large neck circumference (p = 0.0054) and high snoring index (p = 0.0119) were independent predictors for obstructive sleep apnea. Moreover, between the obstructive sleep apnea severity groups, there was a strong tendency of difference in body mass index (p = 0.0441) and neck circumference (p = 0.0846). However, there was no significant difference in snoring frequency according to obstructive sleep apnea severity (p = 0.4914). Conclusions: We confirmed that snoring frequency is a predictor of obstructive sleep apnea. In addition, we showed for the first time that snoring frequency is not associated with obstructive sleep apnea severity, thus it is not a valuable marker for predicting obstructive sleep apnea severity.

코골이와 폐쇄성수면무호흡증 환자에서 무호흡 심도에 따른 구강내 장치의 치료효과 및 환자의 적응도에 관한 연구

안홍균,이광호,정성창 대한안면통증구강내과학회 1998 Journal of Oral Medicine and Pain Vol.23 No.4

The purpose of this Study was to examine the efficacy and compliance of a mandibular advancement device(MAD) according to the severity of sleep apnea in the snorers and obstructive sleep apnea patients. Fifty-four patients (45 males, 9 females, aged 20 - 68years ) who visited Seoul National Uiversity Dental Hospital(SNUDH) to seek for the treatment of snoring and sleep apnea were classified into four groups according to the results of the nocturnal polysomnography and they were instructed to wear MAD regularly which was designed to increase the size of the upper airway by advancing the mandible. The evaluation of the efficacy and compliance of the MAD according to the severity of apnea and the duration after the usage of MAD ( 1week, 1month, 3months, 6months, 12months) was made by using quesionnaires mad in Department of Oral Medicine and Oral diagnosis, SNUDH. The obtained results were as follows : 1. All subjects results were habitual snoreres and 43 patients(79.6%) complained the loudness of snoring that can be heard out of the room. 2. Apnea index(AI) of the total subjects was mean 29.4$\pm$26.9 and respiratory disturbance index(RDI)was mean 37.6$\pm$28.0. And there was nodifference in the efficacy and the compliances of MAD according to the severity of apnea. 3. The severityi of apnea by the questionnaires significantly corresponded with the results of nocturnal polysomnography, and this fact potentiated the diagnostic value of the questionnaire. 4. after the usage of MAD, there was significant improvement in the frequency of snoring, the loudness of snoring, frequency of apnea, daytime sleepiness nad the refreshment after sleep(p<0.001) regardless of the apnea index(AI) and respiratory distrubance index(RDI). 5. The degree of the satisfaction with MAD was mean 74.4$\pm$18.4% and that of the discomfort with the MAD was 31.4$\pm$19.6%. But there was no serious complication in occlusion and temporomandibular joint with the usage of MAD and the duration of the discomfort was mean 3.3$\pm$2.2 weeks. 6. Forty-one patients(75.9%) continued the usage of MAD but thirteen patients(24.1%) stopped the use of MAD because of the discomforts and insufficient results with it.