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Orozco González BN, Rodriguez Plascencia N, Palma Zapata JA, Llamas Domínguez AE, Rodríguez González JS, Diaz JM, Ponce Muñoz M, Ponce-Campos SD. Obesity hypoventilation syndrome, literature review. SLEEP ADVANCES : A JOURNAL OF THE SLEEP RESEARCH SOCIETY 2024; 5:zpae033. [PMID: 38966619 PMCID: PMC11223067 DOI: 10.1093/sleepadvances/zpae033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 05/12/2024] [Indexed: 07/06/2024]
Abstract
Obesity is a global health concern that has been increasing over the years, and it is associated with several pathophysiological changes affecting the respiratory system, including alveolar hypoventilation. Obesity hypoventilation syndrome (OHS) is one of the six subtypes of sleep-hypoventilation disorders. It is defined as the presence of obesity, chronic alveolar hypoventilation leading to daytime hypercapnia and hypoxia, and sleep-disordered breathing. The existence of a sleep disorder is one of the characteristics that patients with OHS present. Among them, 90% of patients have obstructive sleep apnea (OSA), and the remaining 10% of patients with OHS have non-obstructive sleep hypoventilation without OSA or with mild OSA. This review aims to provide a comprehensive understanding of the epidemiological and pathophysiological impact of OHS and to highlight its clinical features, prognosis, and severity, as well as the available treatment options.
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Affiliation(s)
| | - Nidia Rodriguez Plascencia
- Pneumology Service, Hospital of Specialties at the National Medical Center of the West (IMSS), Guadalajara, México
| | | | | | | | - Juan Manuel Diaz
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada
| | - Miguel Ponce Muñoz
- Department of Medicine, Autonomous University of Aguascalientes, Aguascalientes, México
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Huang YC, Huang SH, Chung RJ, Wang BL, Chung CH, Chien WC, Sun CA, Yu PC, Lu CH. Obese Patients Experience More Severe CSA than Non-Obese Patients. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19031289. [PMID: 35162313 PMCID: PMC8835470 DOI: 10.3390/ijerph19031289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 12/04/2022]
Abstract
Objective: To investigate whether central sleep apnea (CSA) is associated with an increased risk of obesity. Materials and methods: From 1 January 2000 to 31 December 2015, we screened 24,363 obese patients from the 2005 longitudinal health insurance database, which is part of the Taiwan National Health Insurance Research Database. From the same database, 97,452 non-obese patients were also screened out. Age, gender, and index dates were matched. Multiple logistic regression was used to analyze the previous exposure risk of obese and CSA patients. A p-value of <0.05 was considered significant. Results: Obese patients were more likely to be exposed to CSA than non-obese patients would (AOR = 2.234, 95% CI = 1.483–4.380, p < 0.001). In addition, the closeness of the exposure time to the index time is positively correlated with the severity of obesity and has a dose–response effect (CSA exposure < 1 year, AOR = 2.386; CSA exposure ≥ 1 year and <5 years, AOR = 1.725; CSA exposure time ≥ 5 years, AOR = 1.422). The CSA exposure time of obese patients was 1.693 times that of non-obese patients. Longer exposure time is associated with more severe obesity and has a dose-response effect (CSA exposure < 1 year, AOR = 1.420; CSA exposure ≥ 1 year and <5 years, AOR = 2.240; CSA ≥ 5 years, AOR = 2.863). Conclusions: In this case-control study, patients with CSA had a significantly increased risk of obesity. Long-term exposure to CSA and obesity is more likely and has a dose-response effect.
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Affiliation(s)
- Yao-Ching Huang
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), Taipei 10608, Taiwan; (Y.-C.H.); (S.-H.H.); (R.-J.C.)
- Department of Medical Research, Tri-Service General Hospital, Taipei 11490, Taiwan;
| | - Shi-Hao Huang
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), Taipei 10608, Taiwan; (Y.-C.H.); (S.-H.H.); (R.-J.C.)
| | - Ren-Jei Chung
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), Taipei 10608, Taiwan; (Y.-C.H.); (S.-H.H.); (R.-J.C.)
| | - Bing-Long Wang
- School of Public Health, National Defense Medical Center, Taipei 11490, Taiwan;
| | - Chi-Hsiang Chung
- Department of Medical Research, Tri-Service General Hospital, Taipei 11490, Taiwan;
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 11490, Taiwan
- Taiwanese Injury Prevention and Safety Promotion Association (TIPSPA), Taipei 11490, Taiwan
| | - Wu-Chien Chien
- Department of Medical Research, Tri-Service General Hospital, Taipei 11490, Taiwan;
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 11490, Taiwan
- Taiwanese Injury Prevention and Safety Promotion Association (TIPSPA), Taipei 11490, Taiwan
- Correspondence: (W.-C.C.); (C.-H.L.)
| | - Chien-An Sun
- Department of Public Health, College of Medicine, Fu-Jen Catholic University, New Taipei City 242062, Taiwan;
- Big Data Center, College of Medicine, Fu-Jen Catholic University, New Taipei City 242062, Taiwan
| | - Pi-Ching Yu
- Graduate Institute of Medicine, National Defense Medical Center, Taipei 11490, Taiwan;
- Cardiovascular Intersive Care Unit, Department of Critical Care Medicine, Far-Eastern Memorial Hospital, New Taipei City 10602, Taiwan
| | - Chieh-Hua Lu
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Tri-Service General Hospital, School of Medicine, National Defense Medical Center, Taipei 11490, Taiwan
- Correspondence: (W.-C.C.); (C.-H.L.)
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Elucidating Predictors of Obesity Hypoventilation Syndrome in a Large Bariatric Surgery Cohort. Ann Am Thorac Soc 2021; 17:1279-1288. [PMID: 32526148 DOI: 10.1513/annalsats.202002-135oc] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Rationale: Although understanding predictors of obesity hypoventilation syndrome (OHS), a condition associated with increased morbidity and mortality, is of key importance for risk prediction, existing characterization is limited.Objectives: We hypothesize that OHS patients referred for bariatric surgery have more severe obstructive sleep apnea and metabolic derangements compared with their eucapnic counterparts.Methods: A total of 1,718 patients undergoing polysomnography with end-tidal CO2 monitoring prior to bariatric surgery at Cleveland Clinic from September 2011 to September 2018 were included. OHS was defined by body mass index (BMI) ≥ 30 kg/m2 and either polysomnography-based end-tidal CO2 ≥ 45 mm Hg or serum bicarbonate levels ≥ 27 mEq/L based on the updated European Respiratory Society guidelines. Unadjusted and multivariable logistic regression models (odds ratio; 95% confidence interval) were used to examine OHS predictors consisting of factors in domains of patient characteristics, polysomnography (cardiorespiratory and sleep architecture), laboratory, and metabolic parameters.Results: The analytic sample comprised 1,718 patients with the following characteristics: age of 45.3 ± 12.1 years, 20.7% were male, BMI = 48.6 ± 9 kg/m2, and 63.6% were white individuals. OHS prevalence was 68.4%. Unadjusted analyses revealed a 1.5% increased odds of OHS (1.01; 1.00-1.03) per 1-unit BMI increase, 1.7% (1.02; 1.01-1.02) per 1% increase in sleep time SaO2 < 90%, 12% increase (1.12; 1.03-1.22) per 1-U increase in hemoglobin A1c, and 3.4% increased odds (1.03; 1.02-1.05) per 5-U increase in apnea-hypopnea index. The association of apnea-hypopnea index with OHS persisted after adjustment for age, sex, race, and BMI and its comorbidities (1.02; 1.01-1.04).Conclusions: OHS was highly prevalent in patients referred for bariatric surgery by more than two-thirds. Even after consideration of confounders including obesity, obstructive sleep apnea remained a strong OHS predictor, as were increasing age, male sex, nocturnal hypoxia, and impaired long-term glucose control. These findings can inform OHS risk stratification in bariatric surgery and set the stage for experimental studies to examine sleep-related respiratory and metabolic contributions to hypoventilation.
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Braganza MV, Hanly PJ, Fraser KL, Tsai WH, Pendharkar SR. Predicting CPAP failure in patients with suspected sleep hypoventilation identified on ambulatory testing. J Clin Sleep Med 2020; 16:1555-1565. [PMID: 32501210 DOI: 10.5664/jcsm.8616] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
STUDY OBJECTIVES Home sleep apnea testing (HSAT) is commonly used to diagnose obstructive sleep apnea, but its role in identifying patients with suspected hypoventilation or predicting their response to continuous positive airway pressure (CPAP) therapy has not been assessed. The primary objective was to determine if HSAT, combined with clinical variables, could predict the failure of CPAP to correct nocturnal hypoxemia during polysomnography in a population with suspected hypoventilation. Secondary objectives were to determine if HSAT and clinical parameters could predict awake or sleep hypoventilation. METHODS A retrospective review was performed of 142 consecutive patients who underwent split-night polysomnography for suspected hypoventilation after clinical assessment by a sleep physician and review of HSAT. We collected quantitative indices of nocturnal hypoxemia, patient demographics, medications, pulmonary function tests, as well as arterial blood gas data from the night of the polysomnography . CPAP failure was defined as persistent obstructive sleep apnea, hypoxemia (oxygen saturation measured by pulse oximetry < 85%), or hypercapnia despite maximal CPAP. RESULTS Failure of CPAP was predicted by awake oxygen saturation and arterial blood gas results but not by HSAT indices of nocturnal hypoxemia. Awake oxygen saturation ≥ 94% ruled out CPAP failure, and partial pressure of oxygen measured by arterial blood gas ≥ 68 mmHg decreased the likelihood of CPAP failure significantly. CONCLUSIONS In patients with suspected hypoventilation based on clinical review and HSAT interpretation by a sleep physician, awake oxygen saturation measured by pulse oximetry and partial pressure of oxygen measured by arterial blood gas can reliably identify patients in whom CPAP is likely to fail. Additional research is required to determine the role of HSAT in the identification and treatment of patients with hypoventilation.
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Affiliation(s)
- Michael V Braganza
- Sleep Centre, Foothills Medical Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Patrick J Hanly
- Sleep Centre, Foothills Medical Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Kristin L Fraser
- Sleep Centre, Foothills Medical Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Willis H Tsai
- Sleep Centre, Foothills Medical Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Sachin R Pendharkar
- Sleep Centre, Foothills Medical Centre, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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Athayde RABD, Oliveira Filho JRBD, Lorenzi Filho G, Genta PR. Obesity hypoventilation syndrome: a current review. ACTA ACUST UNITED AC 2019; 44:510-518. [PMID: 30726328 PMCID: PMC6459748 DOI: 10.1590/s1806-37562017000000332] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 02/11/2018] [Indexed: 02/06/2023]
Abstract
Obesity hypoventilation syndrome (OHS) is defined as the presence of obesity (body mass index ≥ 30 kg/m²) and daytime arterial hypercapnia (PaCO2 ≥ 45 mmHg) in the absence of other causes of hypoventilation. OHS is often overlooked and confused with other conditions associated with hypoventilation, particularly COPD. The recognition of OHS is important because of its high prevalence and the fact that, if left untreated, it is associated with high morbidity and mortality. In the present review, we address recent advances in the pathophysiology and management of OHS, the usefulness of determination of venous bicarbonate in screening for OHS, and diagnostic criteria for OHS that eliminate the need for polysomnography. In addition, we review advances in the treatment of OHS, including behavioral measures, and recent studies comparing the efficacy of continuous positive airway pressure with that of noninvasive ventilation.
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Affiliation(s)
- Rodolfo Augusto Bacelar de Athayde
- . Serviço de Pneumologia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil.,. Laboratório do Sono, Disciplina de Pneumologia, Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | | | - Geraldo Lorenzi Filho
- . Laboratório do Sono, Disciplina de Pneumologia, Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | - Pedro Rodrigues Genta
- . Laboratório do Sono, Disciplina de Pneumologia, Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
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Pıhtılı A, Bingöl Z, Kıyan E. The Predictors of Obesity Hypoventilation Syndrome in Obstructive Sleep Apnea. Balkan Med J 2017; 34:41-46. [PMID: 28251022 PMCID: PMC5322510 DOI: 10.4274/balkanmedj.2015.1797] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Accepted: 02/11/2016] [Indexed: 12/01/2022] Open
Abstract
Background: As obesity increases, the frequency of obstructive sleep apnea and obesity hypoventilation syndrome increases also. However, obesity hypoventilation syndrome frequency is not known, as capnography and arterial blood gas analysis are not routinely performed in sleep laboratories. Aims: To investigate the frequency and predictors of obesity hypoventilation syndrome in obese subjects. Study Design: Retrospective clinical study. Methods: Obese subjects who had arterial blood gas analysis admitted to the sleep laboratory and polysomnography were retrospectively analyzed. Subjects with restrictive (except obesity) and obstructive pulmonary pathologies were excluded. Demographics, Epworth-Sleepiness-Scale scores, polysomnographic data, arterial blood gas analysis, and spirometric measurements were recorded. Results: Of the 419 subjects, 45.1% had obesity hypoventilation syndrome. Apnea hypopnea index (p<0.001), oxygen desaturation index (p<0.001) and sleep time with SpO2<90% (p<0.001) were statistically higher in subjects with obesity hypoventilation syndrome compared to subjects with eucapnic obstructive sleep apnea. The nocturnal mean SpO2 (p<0.001) and lowest SpO2 (p<0.001) were also statistically lower in subjects with obesity hypoventilation syndrome. Logistic regression analysis showed that the lowest SpO2, oxygen desaturation index, apnea hypopnea index and sleep time with SpO2 <90% were related factors for obesity hypoventilation syndrome. Conclusion: Obesity hypoventilation syndrome should be considered when oxygen desaturation index, apnea hypopnea index and sleep time with SpO2 <90% are high.
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Affiliation(s)
- Aylin Pıhtılı
- Department of Pulmonary Medicine, İstanbul Haydarpaşa Numune Training and Research Hospital, İstanbul, Turkey
| | - Züleyha Bingöl
- İstanbul University School of Medicine, Department of Pulmonary Medicine, İstanbul, Turkey
| | - Esen Kıyan
- İstanbul University School of Medicine, Department of Pulmonary Medicine, İstanbul, Turkey
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The Bariatric Airway. Int Anesthesiol Clin 2016; 55:65-85. [PMID: 27941367 DOI: 10.1097/aia.0000000000000133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Vavougios GD, George D G, Pastaka C, Zarogiannis SG, Gourgoulianis KI. Phenotypes of comorbidity in OSAS patients: combining categorical principal component analysis with cluster analysis. J Sleep Res 2016; 25:31-8. [PMID: 26365653 DOI: 10.1111/jsr.12344] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 08/15/2015] [Indexed: 12/31/2022]
Abstract
Phenotyping obstructive sleep apnea syndrome's comorbidity has been attempted for the first time only recently. The aim of our study was to determine phenotypes of comorbidity in obstructive sleep apnea syndrome patients employing a data-driven approach. Data from 1472 consecutive patient records were recovered from our hospital's database. Categorical principal component analysis and two-step clustering were employed to detect distinct clusters in the data. Univariate comparisons between clusters included one-way analysis of variance with Bonferroni correction and chi-square tests. Predictors of pairwise cluster membership were determined via a binary logistic regression model. The analyses revealed six distinct clusters: A, 'healthy, reporting sleeping related symptoms'; B, 'mild obstructive sleep apnea syndrome without significant comorbidities'; C1: 'moderate obstructive sleep apnea syndrome, obesity, without significant comorbidities'; C2: 'moderate obstructive sleep apnea syndrome with severe comorbidity, obesity and the exclusive inclusion of stroke'; D1: 'severe obstructive sleep apnea syndrome and obesity without comorbidity and a 33.8% prevalence of hypertension'; and D2: 'severe obstructive sleep apnea syndrome with severe comorbidities, along with the highest Epworth Sleepiness Scale score and highest body mass index'. Clusters differed significantly in apnea-hypopnea index, oxygen desaturation index; arousal index; age, body mass index, minimum oxygen saturation and daytime oxygen saturation (one-way analysis of variance P < 0.0001). Binary logistic regression indicated that older age, greater body mass index, lower daytime oxygen saturation and hypertension were associated independently with an increased risk of belonging in a comorbid cluster. Six distinct phenotypes of obstructive sleep apnea syndrome and its comorbidities were identified. Mapping the heterogeneity of the obstructive sleep apnea syndrome may help the early identification of at-risk groups. Finally, determining predictors of comorbidity for the moderate and severe strata of these phenotypes implies a need to take these factors into account when considering obstructive sleep apnea syndrome treatment options.
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Argun Baris S, Tuncel D, Ozerdem C, Kutlu H, Onyilmaz T, Basyigit I, Boyaci H, Yildiz F. The effect of positive airway pressure therapy on neurocognitive functions, depression and anxiety in obesity hypoventilation syndrome. Multidiscip Respir Med 2016; 11:35. [PMID: 27766147 PMCID: PMC5057438 DOI: 10.1186/s40248-016-0071-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/18/2016] [Indexed: 01/22/2023] Open
Abstract
Background The aim of this study is to evaluate the presence of neurocognitive dysfunctions, depression and anxiety and the effect of positive airway pressure (PAP) therapy on these alterations in Obesity Hypoventilation Syndrome (OHS) patients. Methods Ten healthy normal and obese controls, 10 OHS and 10 OSAS patients were included in the study. Short form-36, Beck Depression Scale and State-Trade Anxiety Inventory (STAI 1-2) were performed. Wisconsin Card Sorting Test (WCST), Montreal Cognitive Assessment Scale (MOCA), Enhanced Cued Recall (ECR) and Mini Mental Test (MMT) were used for neurocognitive evaluation. All tests were repeated after one night PAP therapy in OHS and OSAS groups. Results OHS patients had the lowest scores of physical (PF) and social functioning (SF) in SF-36. The total number of persistent errors and incorrect answers were the highest in OHS group in WCST. The scores of MOCA, ECR and MMT were lower; depression and anxiety scores were higher in OHS group than in controls (p = 0,00). There was a significant increase in the completed categories in OHS after PAP therapy (p = 0,03). There were also significant increases in MOCA, ECR and MMT scores and significant decreases in depression and anxiety scores with respect to PAP therapy. Conclusions Cognitive dysfunction, depression and anxiety are important under-recognized comorbidities in OHS. It is suggested that short term PAP therapy had positive effects on neurocognitive functions, depression and anxiety but further multicentre, prospective studies with large number of cases are needed to evaluate the effect of long term PAP therapy on these parameters.
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Affiliation(s)
- Serap Argun Baris
- Department of Pulmonary Diseases, Kocaeli University School of Medicine, Umuttepe, İzmit, Kocaeli Turkey
| | - Dilek Tuncel
- Department of Pulmonary Diseases, Kocaeli University School of Medicine, Umuttepe, İzmit, Kocaeli Turkey
| | - Cigdem Ozerdem
- Department of Neurology, Derince Training and Research Hospital, İzmit, Kocaeli Turkey
| | - Huseyin Kutlu
- Department of Pyschiatry, Kocaeli University School of Medicine, İzmit, Kocaeli Turkey
| | - Tugba Onyilmaz
- Department of Pulmonary Diseases, Private Konak Hospital, İzmit, Kocaeli Turkey
| | - Ilknur Basyigit
- Department of Pulmonary Diseases, Kocaeli University School of Medicine, Umuttepe, İzmit, Kocaeli Turkey
| | - Hasim Boyaci
- Department of Pulmonary Diseases, Kocaeli University School of Medicine, Umuttepe, İzmit, Kocaeli Turkey
| | - Fusun Yildiz
- Department of Pulmonary Diseases, Kocaeli University School of Medicine, Umuttepe, İzmit, Kocaeli Turkey
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Vold ML, Aasebø U, Wilsgaard T, Melbye H. Low oxygen saturation and mortality in an adult cohort: the Tromsø study. BMC Pulm Med 2015; 15:9. [PMID: 25885261 PMCID: PMC4342789 DOI: 10.1186/s12890-015-0003-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 01/20/2015] [Indexed: 11/18/2022] Open
Abstract
Background Oxygen saturation has been shown in risk score models to predict mortality in emergency medicine. The aim of this study was to determine whether low oxygen saturation measured by a single-point measurement by pulse oximetry (SpO2) is associated with increased mortality in the general adult population. Methods Pulse oximetry was performed in 5,152 participants in a cross-sectional survey in Tromsø, Norway, in 2001–2002 (“Tromsø 5”). Ten-year follow-up data for all-cause mortality and cause of death were obtained from the National Population and the Cause of Death Registries, respectively. Cause of death was grouped into four categories: cardiovascular disease, cancer except lung cancer, pulmonary disease, and others. SpO2 categories were assessed as predictors for all-cause mortality and death using Cox proportional-hazards regression models after correcting for age, sex, smoking history, body mass index (BMI), C-reactive protein level, self-reported diseases, respiratory symptoms, and spirometry results. Results The mean age was 65.8 years, and 56% were women. During the follow-up, 1,046 (20.3%) participants died. The age- and sex-adjusted hazard ratios (HRs) (95% confidence intervals) for all-cause mortality were 1.99 (1.33–2.96) for SpO2 ≤ 92% and 1.36 (1.15–1.60) for SpO2 93–95%, compared with SpO2 ≥ 96%. In the multivariable Cox proportional-hazards regression models that included self-reported diseases, respiratory symptoms, smoking history, BMI, and CRP levels as the explanatory variables, SpO2 remained a significant predictor of all-cause mortality. However, after including forced expiratory volume in 1 s percent predicted (FEV1% predicted), this association was no longer significant. Mortality caused by pulmonary diseases was significantly associated with SpO2 even when FEV1% predicted was included in the model. Conclusions Low oxygen saturation was independently associated with increased all-cause mortality and mortality caused by pulmonary diseases. When FEV1% predicted was included in the analysis, the strength of the association weakened but was still statistically significant for mortality caused by pulmonary diseases.
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Affiliation(s)
- Monica Linea Vold
- Department of Respiratory Medicine, University Hospital of North Norway, 9038, Tromsø, Norway. .,Department of Community Medicine, University of Tromsø, Tromsø, Norway.
| | - Ulf Aasebø
- Department of Respiratory Medicine, University Hospital of North Norway, 9038, Tromsø, Norway. .,Department of Clinical Medicine, University of Tromsø, Tromsø, Norway.
| | - Tom Wilsgaard
- Department of Community Medicine, University of Tromsø, Tromsø, Norway.
| | - Hasse Melbye
- Department of Community Medicine, University of Tromsø, Tromsø, Norway.
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Abstract
Obesity hypoventilation syndrome is a respiratory consequence of morbid obesity that is characterized by alveolar hypoventilation during sleep and wakefulness. The disorder involves a complex interaction between impaired respiratory mechanics, ventilatory drive and sleep-disordered breathing. Early diagnosis and treatment is important, because delay in treatment is associated with significant mortality and morbidity. Available treatment options include non-invasive positive airway pressure (PAP) therapies and weight loss. There is limited long-term data regarding the effectiveness of such therapies. This review outlines the current concepts of clinical presentation, diagnostic and management strategies to help identify and treat patients with obesity-hypoventilation syndromes.
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12
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Alawami M, Mustafa A, Whyte K, Alkhater M, Bhikoo Z, Pemberton J. Echocardiographic and electrocardiographic findings in patients with obesity hypoventilation syndrome. Intern Med J 2015; 45:68-73. [DOI: 10.1111/imj.12620] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 10/27/2014] [Indexed: 11/27/2022]
Affiliation(s)
- M. Alawami
- Green Lane Cardiovascular Services; Auckland City Hospital; Auckland New Zealand
| | - A. Mustafa
- Green Lane Cardiovascular Services; Auckland City Hospital; Auckland New Zealand
| | - K. Whyte
- Respiratory Services; Auckland City Hospital; Auckland New Zealand
| | - M. Alkhater
- Respiratory Department; Waikato Hospital; Hamilton New Zealand
| | - Z. Bhikoo
- Respiratory Department; Waikato Hospital; Hamilton New Zealand
| | - J. Pemberton
- Green Lane Cardiovascular Services; Auckland City Hospital; Auckland New Zealand
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13
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Vold ML, Aasebø U, Melbye H. Low FEV1, smoking history, and obesity are factors associated with oxygen saturation decrease in an adult population cohort. Int J Chron Obstruct Pulmon Dis 2014; 9:1225-33. [PMID: 25364242 PMCID: PMC4211871 DOI: 10.2147/copd.s69438] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Background Worsening of pulmonary diseases is associated with a decrease in oxygen saturation (SpO2). Such a decrease in SpO2 and associated factors has not been previously evaluated in a general adult population. Aim We sought to describe SpO2 in a sample of adults, at baseline and after 6.3 years, to determine whether factors predicting low SpO2 in a cross-sectional study were also associated with a decrease in SpO2 in this cohort. Methods As part of the Tromsø Study, 2,822 participants were examined with pulse oximetry in Tromsø 5 (2001/2002) and Tromsø 6 (2007/2008). Low SpO2 by pulse oximetry was defined as an SpO2 ≤95%, and SpO2 decrease was defined as a ≥2% decrease from baseline to below 96%. Results A total of 139 (4.9%) subjects had a decrease in SpO2. Forced expiratory volume in 1 second (FEV1) <50% of the predicted value and current smoking with a history of ≥10 pack-years were the baseline characteristics most strongly associated with an SpO2 decrease in multivariable logistic regression (odds ratio 3.55 [95% confidence interval (CI) 1.60–7.89] and 2.48 [95% CI 1.48–4.15], respectively). Male sex, age, former smoking with a history of ≥10 pack-years, body mass index ≥30 kg/m2, and C-reactive protein ≥5 mg/L were also significantly associated with an SpO2 decrease. A significant decrease in FEV1 and a new diagnosis of asthma or chronic obstructive pulmonary disease during the observation period most strongly predicted a fall in SpO2. A lower SpO2 decrease was observed in those who quit smoking and those who lost weight, but these tendencies were not statistically significant. Conclusion A decrease in SpO2 was most strongly associated with severe airflow limitation and a history of smoking. Smoking cessation and reducing obesity seem to be important measures to target for avoiding SpO2 decreases in the general population.
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Affiliation(s)
- Monica Linea Vold
- Department of Respiratory Medicine, University Hospital of North Norway, Tromsø, Norway ; Department of Community Medicine, University of Tromsø, Tromsø, Norway
| | - Ulf Aasebø
- Department of Respiratory Medicine, University Hospital of North Norway, Tromsø, Norway ; Department of Clinical Medicine, University of Tromsø, Tromsø, Norway
| | - Hasse Melbye
- Department of Community Medicine, University of Tromsø, Tromsø, Norway
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Balachandran JS, Masa JF, Mokhlesi B. Obesity Hypoventilation Syndrome Epidemiology and Diagnosis. Sleep Med Clin 2014; 9:341-347. [PMID: 25360072 DOI: 10.1016/j.jsmc.2014.05.007] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Jay S Balachandran
- Sleep Disorders Center, Section of Pulmonary and Critical Care, Department of Medicine, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA
| | - Juan Fernando Masa
- Pulmonary Division, San Pedro de Alcantara Hospital, Avda. Pablo Naranjo s/n, Caceres 10003, Spain ; CIBERES National Research Network, Avd. Montforte de Lemos 5, Pabellon 11, Madrid 28029, Spain
| | - Babak Mokhlesi
- Sleep Disorders Center, Section of Pulmonary and Critical Care, Department of Medicine, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA
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Macavei VM, Spurling KJ, Loft J, Makker HK. Diagnostic predictors of obesity-hypoventilation syndrome in patients suspected of having sleep disordered breathing. J Clin Sleep Med 2014; 9:879-84. [PMID: 23997700 DOI: 10.5664/jcsm.2986] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Obesity-hypoventilation syndrome (OHS) is associated with significant morbidity and mortality and requires measurement of arterial pCO2 for diagnosis. OBJECTIVE To determine diagnostic predictors of OHS among obese patients with suspected obstructive sleep apnea/hypopnea syndrome (OSAHS). METHODS Retrospective analysis of data on 525 sleep clinic patients (mean age 51.4 ± 12.7 years; 65.7% males; mean BMI 34.5 ± 8.1). All patients had sleep studies, and arterialized capillary blood gases (CBG) were measured in obese subjects (BMI > 30 kg/m2). RESULTS Of 525 patients, 65.5% were obese, 37.2% were morbidly obese (BMI > 40 kg/m2); 52.3% had confirmed OSAHS. Hypercapnia (pCO2 > 6 kPa or 45 mm Hg) was present in 20.6% obese and 22.1% OSAHS patients. Analysis of OHS predictors showed significant correlations between pCO2 and BMI, FEV1, FVC, AHI, mean and minimum nocturnal SpO2, sleep time with SpO2 < 90%, pO2, and calculated HCO3 from the CBG. PO2 and HCO3 were independent predictors of OHS, explaining 27.7% of pCO2 variance (p < 0.0001). A calculated HCO3 cutoff > 27 mmol/L had 85.7% sensitivity and 89.5% specificity for diagnosis of OHS, with 68.1% positive and 95.9% negative predictive value. CONCLUSION We confirmed a high prevalence of OHS in obese OSAHS patients (22.1%) and high calculated HCO3 level (> 27 mmol/L) to be a sensitive and specific predictor for the diagnosis of OHS.
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Affiliation(s)
- Vladimir M Macavei
- Sleep and Ventilation Unit, Department of Respiratory Medicine, North Middlesex University Hospital, London, UK.
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16
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Central sleep apnea in obese children with sleep-disordered breathing. Int J Obes (Lond) 2013; 38:27-31. [PMID: 24048143 DOI: 10.1038/ijo.2013.184] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 09/08/2013] [Indexed: 01/08/2023]
Abstract
OBJECTIVES In contrast to obstructive sleep apnea (OSA), central sleep apnea (CSA) in obese children has received lesser attention. As pediatric CSA is more prevalent than expected and adversely impacts health, this study aims to elucidate the major factors associated with central apnea index (CAI) and compare CSA between obese and non-obese children. METHODS Retrospective analysis was performed in a tertiary referral medical center. Children with sleep-disordered breathing (SDB) ranging from 2-18 years old were enrolled. All participants completed history taking, otolaryngological examination and overnight polysomnography. CSA was defined as having CAI exceeding 1 h(-1). CAI and the prevalence of CSA were analyzed in children of different age groups, weight statuses and adenotonsillar sizes. RESULTS A total of 487 cases were included. The prevalence of CSA was 13.3% (65/487). CAI was negatively correlated with age (r=-0.32, P<0.001). Obese children had a significantly lower CAI than that of non-obese ones (0.20 ± 0.36 vs 0.48 ± 0.82 h(-1), P<0.001). Multiple linear regression analysis demonstrated a relationship between CAI, age and obesity as 'CAI=0.883-0.055 × Age -0.22 × (Obesity)'. CONCLUSIONS In children with SDB, younger ones have a significantly higher CAI than older ones. Additionally, obese children had a lower CAI than non-obese ones.
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17
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Predictors of oxygen saturation ≤95% in a cross-sectional population based survey. Respir Med 2012; 106:1551-8. [DOI: 10.1016/j.rmed.2012.06.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/06/2012] [Accepted: 06/24/2012] [Indexed: 11/19/2022]
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18
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Akinnusi ME, Saliba R, Porhomayon J, El-Solh AA. Sleep disorders in morbid obesity. Eur J Intern Med 2012; 23:219-26. [PMID: 22385877 DOI: 10.1016/j.ejim.2011.10.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 10/16/2011] [Accepted: 10/22/2011] [Indexed: 10/15/2022]
Abstract
The increasing prevalence of obesity has lead to an increase in the prevalence of sleep disordered breathing in the general population. The disproportionate structural characteristics of the pharyngeal airway and the diminished neural regulation of the pharyngeal dilating muscles during sleep predispose the obese patients to pharyngeal airway collapsibility. A subgroup of obese apneic patients is unable to compensate for the added load of obesity on the respiratory system, with resultant daytime hypercapnia. Weight loss using dietary modification and life style changes is the safest approach to reducing the severity of sleep apnea, but its efficacy is limited on the long run. Although it has inherent risks, bariatric surgery provides the most immediate result in alleviating sleep apnea. Obesity has been linked also to narcolepsy. The loss of neuropeptides co-localized in hypocretin neurons is suggested as the potential mechanism. Poor sleep quality, which leads to overall sleep loss and excessive daytime sleepiness has also become a frequent complaint in this population. Identifying abnormal nocturnal eating is critically important for patient care. Both sleep related eating disorder and night eating syndrome are treatable and represent potentially reversible forms of obesity.
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Abstract
Obesity is becoming a major medical concern in several parts of the world, with huge economic impacts on health- care systems, resulting mainly from increased cardiovascular risks. At the same time, obesity leads to a number of sleep-disordered breathing patterns like obstructive sleep apnea and obesity hypoventilation syndrome (OHS), leading to increased morbidity and mortality with reduced quality of life. OHS is distinct from other sleep- related breathing disorders although overlap may exist. OHS patients may have obstructive sleep apnea/hypopnea with hypercapnia and sleep hypoventilation, or an isolated sleep hypoventilation. Despite its major impact on health, this disorder is under-recognized and under-diagnosed. Available management options include aggressive weight reduction, oxygen therapy and using positive airway pressure techniques. In this review, we will go over the epidemiology, pathophysiology, presentation and diagnosis and management of OHS.
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Affiliation(s)
- Laila Al Dabal
- Department of Pulmonary Medicine, Rashid Hospital, Dubai Health Authority, UAE
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Acute ventilatory failure complicating obesity hypoventilation: update on a ‘critical care syndrome’. Curr Opin Pulm Med 2010; 16:543-51. [DOI: 10.1097/mcp.0b013e32833ef52e] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Prevalence and clinical characteristics of obesity hypoventilation syndrome among individuals reporting sleep-related breathing symptoms in northern Greece. Sleep Breath 2010; 14:381-6. [DOI: 10.1007/s11325-010-0360-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Revised: 04/15/2010] [Accepted: 05/03/2010] [Indexed: 10/19/2022]
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Abstract
Obesity-hypoventilation syndrome (OHS), also historically described as the Pickwickian syndrome, consists of the triad of obesity, sleep disordered breathing, and chronic hypercapnia during wakefulness in the absence of other known causes of hypercapnia. Its exact prevalence is unknown, but it has been estimated that 10% to 20% of obese patients with obstructive sleep apnea have hypercapnia. OHS often remains undiagnosed until late in the course of the disease. Early recognition is important because these patients have significant morbidity and mortality. Effective treatment can lead to significant improvement in patient outcomes, underscoring the importance of early diagnosis. The authors review the definition and epidemiology of OHS, in addition to the current multifaceted understanding of the pathophysiology, and provide useful clinical approaches to diagnosis and treatment.
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Affiliation(s)
- Stephen W Littleton
- Sleep Medicine Fellowship Program, Section of Pulmonary and Critical Care Medicine, University of Chicago, Room W438, Chicago, IL 60637, USA
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Wåhlin-Larsson B, Ulfberg J, Aulin KP, Kadi F. The expression of vascular endothelial growth factor in skeletal muscle of patients with sleep disorders. Muscle Nerve 2009; 40:556-61. [DOI: 10.1002/mus.21357] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kaw R, Hernandez AV, Walker E, Aboussouan L, Mokhlesi B. Determinants of Hypercapnia in Obese Patients With Obstructive Sleep Apnea. Chest 2009; 136:787-796. [DOI: 10.1378/chest.09-0615] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Assessment and management of patients with obesity hypoventilation syndrome. Ann Am Thorac Soc 2008; 5:218-25. [PMID: 18250215 DOI: 10.1513/pats.200708-122mg] [Citation(s) in RCA: 176] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Obesity hypoventilation syndrome (OHS) is characterized by obesity, daytime hypercapnia, and sleep-disordered breathing in the absence of significant lung or respiratory muscle disease. Compared with eucapnic morbidly obese patients and eucapnic patients with sleep-disordered breathing, patients with OHS have increased health care expenses and are at higher risk of developing serious cardiovascular disease leading to early mortality. Despite the significant morbidity and mortality associated with this syndrome, diagnosis and institution of effective treatment occur late in the course of the syndrome. Given that the prevalence of extreme obesity has increased considerably, it is likely that clinicians will encounter patients with OHS in their clinical practice. Therefore maintaining a high index of suspicion can lead to early recognition and treatment reducing the high burden of morbidity and mortality and related health care expenditure associated with undiagnosed and untreated OHS. In this review we define the clinical characteristics of the syndrome and review the pathophysiology, morbidity, and mortality associated with it. Last, we discuss currently available treatment modalities.
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Wåhlin Larsson B, Kadi F, Ulfberg J, Piehl Aulin K. Skeletal Muscle Morphology and Aerobic Capacity in Patients with Obstructive Sleep Apnoea Syndrome. Respiration 2008; 76:21-7. [DOI: 10.1159/000126492] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Accepted: 01/14/2008] [Indexed: 01/06/2023] Open
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Mokhlesi B, Tulaimat A, Faibussowitsch I, Wang Y, Evans AT. Obesity hypoventilation syndrome: prevalence and predictors in patients with obstructive sleep apnea. Sleep Breath 2007; 11:117-24. [PMID: 17187265 DOI: 10.1007/s11325-006-0092-8] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Patients with obesity hypoventilation syndrome (OHS) have a lower quality of life, more healthcare expenses, a greater risk of pulmonary hypertension, and a higher mortality compared to eucapnic patients with obstructive sleep apnea (OSA). Despite significant morbidity and mortality associated with OHS, it is often unrecognized and treatment is frequently delayed. The objective of this observational study was to determine the prevalence of OHS in patients with OSA seen at the sleep disorders clinic of a large public urban hospital serving predominantly minority population and to identify clinical--not mechanistic--predictors that should prompt clinicians to measure arterial blood gases. In the first stage, we randomly selected 180 patients referred to our sleep disorders clinic between 2000 and 2004 for suspicion of OSA. From this retrospective random sample we calculated the prevalence of OHS in patients with OSA and identified independent clinical predictors using logistic regression. In the second stage, we prospectively validated these predictors in a sample of 410 consecutive patients referred to the sleep disorders clinic for suspicion of OSA between 2005 and 2006. The prevalence of OHS in patients with OSA was 30% in the retrospective random sample and 20% in the prospective sample. Three variables independently predicted OHS in both samples: serum bicarbonate level (p < 0.001), apnea-hypopnea index (p = 0.006), and lowest oxygen saturation during sleep (p < 0.001). Due to the serious morbidity associated with OHS, we selected a highly sensitive threshold of serum bicarbonate level. A threshold of 27 mEq/l had a sensitivity of 92% and a specificity of 50%. Only 3% of patients with a serum bicarbonate level <27 mEq/l had hypercapnia compared to 50% with a serum bicarbonate > or =27 mEq/l. In conclusion, OHS is common in severe OSA. A normal serum bicarbonate level excludes hypercapnia and an elevated serum bicarbonate level should prompt clinicians to measure arterial blood gases.
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Affiliation(s)
- Babak Mokhlesi
- Sleep Disorders Center, Section of Pulmonary and Critical Care Medicine, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Ave. L11B, Chicago, IL 60637, USA.
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Ayappa I, Berger KI, Norman RG, Oppenheimer BW, Rapoport DM, Goldring RM. Hypercapnia and ventilatory periodicity in obstructive sleep apnea syndrome. Am J Respir Crit Care Med 2002; 166:1112-5. [PMID: 12379556 DOI: 10.1164/rccm.200203-212oc] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Prevention of acute hypercapnia during obstructive events in obstructive sleep apnea requires a balance between carbon dioxide (CO(2)) loading during the event and CO(2) unloading in the interevent period. Earlier studies have demonstrated that acute CO(2) retention may occur despite high interevent ventilation when the interevent duration is short relative to the duration of the preceding event. The present study examines the relationship between apnea and interapnea durations and relates this assessment of ventilatory periodicity to the degree of chronic hypercapnia in subjects with severe sleep apnea. A total of 18 subjects with sleep apnea (> 40 apnea/hour; chronic awake Pa(CO2) 36-62 mm Hg) and without underlying lung disease underwent polysomnography. For each event, apnea duration, interapnea duration, and apnea/interapnea duration ratio were determined. No relationship was observed between chronic Pa(CO2) and mean apnea or interapnea duration (p > 0.1). However, Pa(CO2) was directly related to apnea/interapnea duration ratio (r = 0.48; p < 0.05) such that with increasing chronic hypercapnia the interapnea duration shortens relative to the apnea duration. The present study suggests that control of the interapnea ventilatory duration relative to the duration of the preceding apnea, is an important component of the integrated ventilatory response to CO(2) loading during apnea and may contribute toward the development and/or maintenance of chronic hypercapnia in obstructive sleep apnea/hypopnea syndrome.
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Affiliation(s)
- Indu Ayappa
- Division of Pulmonary and Critical Care Medicine and Bellevue Hospital Chest Service, Department of Medicine, New York University School of Medicine, New York, New York 10016, USA.
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