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Voulgaris A, Archontogeorgis K, Chadia K, Siopi D, Nena E, Steiropoulos P. Differences in Anthropometric, Sleep and Respiratory Characteristics between Hypercapnic and Normocapnic Patients with COPD-OSA Overlap Syndrome. J Pers Med 2024; 14:600. [PMID: 38929821 PMCID: PMC11204545 DOI: 10.3390/jpm14060600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 05/26/2024] [Accepted: 05/30/2024] [Indexed: 06/28/2024] Open
Abstract
BACKGROUND Overlap syndrome (OS), the coexistence of chronic obstructive pulmonary disease and obstructive sleep apnea, is frequently characterized by the presence of daytime hypercapnia (pCO2 ≥ 45 mmHg). The aim of this study was to investigate potential differences in anthropometric, sleep and respiratory characteristics between hypercapnic and normocapnic patients with OS. METHODS Consecutive patients who underwent polysomnography, pulmonary function testing and arterial blood gases and had been diagnosed with OS were enrolled in the study. RESULTS According to pCO2 levels in wakefulness, the patients were divided into group A, consisting of OS patients without hypercapnia (n = 108) or group B, consisting of OS patients with hypercapnia (n = 55). The majority of included patients in both groups were males (n = 92 in group A vs. n = 50 in group B). Group B had increased BMI (p = 0.001), neck (p = 0.017) and waist circumference (p = 0.013), higher scores in Epworth sleepiness scale (ESS) (p = 0.008), increased sleep efficiency (p = 0.033), oxygen desaturation index (p = 0.004) and time with oxyhemoglobin saturation <90% (p = 0.006) than group A. Also, Group B had decreased average and minimum oxyhemoglobin saturation during sleep (p < 0.001). Hypercapnic patients had lower FEV1% (p = 0.003), FVC% (p = 0.004), pO2 and pCO2 (p < 0.001 for both) values compared with normocapnic patients. In binary regression analysis, which assessed various predictors on the likelihood of having hypercapnia, it was found that BMI (OR: 1.313, 95% CI: 1.048-1.646, p = 0.018) and FVC (OR: 0.913, 95% CI: 0.845-0.986, p = 0.020) were the major determinants of hypercapnia in OS patients. CONCLUSIONS Hypercapnic OS patients were more obese and sleepy and presented worse respiratory function in wakefulness and sleep hypoxia characteristics compared with normocapnic OS patients.
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Affiliation(s)
- Athanasios Voulgaris
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (A.V.); (K.A.); (D.S.)
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Kostas Archontogeorgis
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (A.V.); (K.A.); (D.S.)
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Konstantina Chadia
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Dimitra Siopi
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (A.V.); (K.A.); (D.S.)
| | - Evangelia Nena
- Laboratory of Hygiene and Environmental Protection, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Paschalis Steiropoulos
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (A.V.); (K.A.); (D.S.)
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
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Akyol Gurses A, Akyildiz UO. Predictive value of red cell distribution width for overlap syndrome in obstructive sleep apnea. Front Neurol 2024; 15:1415410. [PMID: 38846032 PMCID: PMC11153708 DOI: 10.3389/fneur.2024.1415410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 05/13/2024] [Indexed: 06/09/2024] Open
Abstract
Purpose Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are prevalent disorders, and the concurrence so-called overlap syndrome (OVS) is not rare either. Early recognition of OVS is essential because this group is more prone to cardiovascular morbidities and requires effective multidisciplinary follow-up. This study aimed to evaluate RDW in patients with severe OSAS and investigate whether it can predict OVS. Patients and methods 96 patients were retrospectively analyzed, of whom 66 were found to have severe OSAS alone and 30 OVS during diagnostic workups. Demographic, polysomnographic, and laboratory results, including RDW, were compared between groups. Multivariate logistic regression was used to determine independent associates of OVS. Results Gender and body mass index (BMI) were similar, however, the mean age and RDW were higher in the OVS group (p:0.008, p:0.002). The increase in RDW remained significant after adjustment for age, BMI, and cardiovascular risk factors. An RDW value of >13.65% was shown to have a 78.3% sensitivity and 60% specificity for predicting OVS in severe OSAS (p:0.004). Conclusion The results suggest that RDW can be a reliable indicator for diagnosing OVS in OSAS. It can help in identifying the subset of patients who would benefit from proper consultations and multidisciplinary follow-up, leading to appropriate treatment of each disease component and effective monitoring to prevent adverse cardiovascular outcomes.
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Affiliation(s)
- Asli Akyol Gurses
- Division of Clinical Neurophysiology, Department of Neurology, School of Medicine, Gazi University, Ankara, Türkiye
- Neuroscience and Neurotechnology Center of Excellence (NÖROM), Gazi University, Ankara, Türkiye
| | - Utku Ogan Akyildiz
- Department of Neurology, School of Medicine, Adnan Menderes University, Aydin, Türkiye
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Fanaridis M, Bouloukaki I, Stathakis G, Steiropoulos P, Tzanakis N, Moniaki V, Mavroudi E, Tsiligianni I, Schiza S. Prevalence and Characteristics of Patients with Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease: Overlap Syndrome. Life (Basel) 2024; 14:547. [PMID: 38792569 PMCID: PMC11122385 DOI: 10.3390/life14050547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 04/21/2024] [Accepted: 04/22/2024] [Indexed: 05/26/2024] Open
Abstract
Overlap syndrome (OVS) is a distinct clinical entity that seems to result in potential cardiovascular consequences. We aimed to estimate the prevalence and risk factors for OVS in OSA patients and analyze clinical and PSG characteristics associated with OVS. In this cross-sectional study, 2616 patients evaluated for OSA underwent type-1 polysomnography (PSG). They were grouped as pure OSA (AHI > 15/h) and OVS patients. Demographics, PSG data, pulmonary function tests and arterial blood gases (ABGs) were compared between groups after adjustments for confounders. OSA was diagnosed in 2108 out of 2616 patients. Of those, 398 (19%) had OVS. Independent predictors of OVS were older age [OR: 5.386 (4.153-6.987)], current/former smoking [OR: 11.577 (7.232-18.532)], BMI [OR: 2.901 (2.082-4.044)] and ABG measurements [PaCO2 ≥ 45 OR: 4.648 (3.078-7.019), PO2 [OR: 0.934 (0.920-0.949)], HCO3- [OR: 1.196 (1.133-1.263), all p < 0.001]. OVS was also associated with prevalent hypertension [OR: 1.345 (1.030-1.758), p = 0.03] and cardiovascular disease [OR: 1.617 (1.229-2.126), p < 0.001], depressive symptoms [OR: 1.741 (1.230-2.465), p = 0.002] and nocturia [OR: 1.944 (1.378-2.742), p < 0.001], as well as with indices of OSA severity. Disturbances in sleep architecture were more prominent in OVS expressed by lower %N3 and REM% and higher arousal index. Our data suggest that OVS is prevalent among OSA patients, with distinct clinical and PSG characteristics. These characteristics could be utilized as predictive factors for early identification and further evaluation of these patients towards desirable patient-reported outcomes.
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Affiliation(s)
- Michail Fanaridis
- Sleep Disorders Center, Department of Respiratory Medicine, School of Medicine, University of Crete, 70013 Heraklion, Greece; (M.F.); (G.S.); (V.M.); (E.M.); (S.S.)
| | - Izolde Bouloukaki
- Sleep Disorders Center, Department of Respiratory Medicine, School of Medicine, University of Crete, 70013 Heraklion, Greece; (M.F.); (G.S.); (V.M.); (E.M.); (S.S.)
- Department of Social Medicine, School of Medicine, University of Crete, 71410 Heraklion, Greece;
| | - Georgios Stathakis
- Sleep Disorders Center, Department of Respiratory Medicine, School of Medicine, University of Crete, 70013 Heraklion, Greece; (M.F.); (G.S.); (V.M.); (E.M.); (S.S.)
| | - Paschalis Steiropoulos
- Department of Respiratory Medicine, Medical School, Democritus University of Thrace, University General Hospital Dragana, 68100 Alexandroupolis, Greece;
| | - Nikos Tzanakis
- Department of Thoracic Medicine, University Hospital of Heraklion, Medical School, University of Crete, 70013 Heraklion, Greece;
| | - Violeta Moniaki
- Sleep Disorders Center, Department of Respiratory Medicine, School of Medicine, University of Crete, 70013 Heraklion, Greece; (M.F.); (G.S.); (V.M.); (E.M.); (S.S.)
| | - Eleni Mavroudi
- Sleep Disorders Center, Department of Respiratory Medicine, School of Medicine, University of Crete, 70013 Heraklion, Greece; (M.F.); (G.S.); (V.M.); (E.M.); (S.S.)
| | - Ioanna Tsiligianni
- Department of Social Medicine, School of Medicine, University of Crete, 71410 Heraklion, Greece;
| | - Sophia Schiza
- Sleep Disorders Center, Department of Respiratory Medicine, School of Medicine, University of Crete, 70013 Heraklion, Greece; (M.F.); (G.S.); (V.M.); (E.M.); (S.S.)
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Voulgaris A, Archontogeorgis K, Apessos I, Paxinou N, Nena E, Steiropoulos P. Is COPD the Determinant Factor for Myocardial Injury and Cardiac Wall Stress in OSA Patients? MEDICINA (KAUNAS, LITHUANIA) 2023; 59:1759. [PMID: 37893477 PMCID: PMC10608258 DOI: 10.3390/medicina59101759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/25/2023] [Accepted: 09/28/2023] [Indexed: 10/29/2023]
Abstract
Background and Objectives: Evidence shows that COPD-OSA overlap syndrome (OS) is more frequently accompanied by cardiovascular disease (CVD) in comparison to either disease alone. The aim of the study was to explore whether patients with OS have a higher burden of subclinical myocardial injury and wall stress compared with OSA patients. Materials and Methods: Consecutive patients, without established CVD, underwent polysomnography and pulmonary function testing, due to suspected sleep-disordered breathing. An equal number of patients with OS (n = 53, with an apnea hypopnea index (AHI) > 5/h and FEV1/FVC < 0.7) and patients with OSA (n = 53, AHI > 5/h and FEV1/FVC > 0.7) were included in the study. The detection of asymptomatic myocardial injury and wall stress was performed via the assessment of serum high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), respectively. Results: OS patients were older (p < 0.001) and had worse hypoxemic parameters, namely average oxyhemoglobin saturation (SpO2) (p = 0.002) and time spent with SpO2 < 90% (p = 0.003) during sleep as well as daytime pO2 (p < 0.001), than patients with OSA. No difference was observed between groups in terms of Epworth Sleepiness Scale (p = 0.432) and AHI (p = 0.587). Both levels of hs-cTnT (14.2 (9.1-20.2) vs. 6.5 (5.6-8.7) pg/mL, p < 0.001) and NT-proBNP (93.1 (37.9-182.5) vs. 19.2 (8.3-35.4) pg/mL, p < 0.001) were increased in OS compared to OSA patients. Upon multivariate linear regression analysis, levels of NT-proBNP and hs-cTnT correlated with age and average SpO2 during sleep. Conclusions: Our study demonstrated higher levels of hs-cTnT and NT-proBNP in OS patients, indicating an increased probability of subclinical myocardial injury and wall stress, compared with OSA individuals.
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Affiliation(s)
- Athanasios Voulgaris
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (K.A.); (N.P.); (P.S.)
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Kostas Archontogeorgis
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (K.A.); (N.P.); (P.S.)
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Ioulianos Apessos
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
- Department of Dentoalveolar Surgery, Implantology and Oral Radiology, School of Dentistry, Aristotle University of Thessaloniki, 56403 Thessaloniki, Greece
| | - Nikoleta Paxinou
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (K.A.); (N.P.); (P.S.)
| | - Evangelia Nena
- Laboratory of Hygiene and Environmental Protection, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Paschalis Steiropoulos
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (K.A.); (N.P.); (P.S.)
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
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Rokou A, Eleftheriou A, Tsigalou C, Apessos I, Nena E, Dalamaga M, Voulgaris A, Steiropoulos P. Effect of the Implementation of a Structured Diet Management Plan on the Severity of Obstructive Sleep Apnea: A Systematic Review. Curr Nutr Rep 2023; 12:26-38. [PMID: 36435894 PMCID: PMC9974698 DOI: 10.1007/s13668-022-00445-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2022] [Indexed: 11/27/2022]
Abstract
PURPOSE OF REVIEW The prevalence of obstructive sleep apnea (OSA) is increasing worldwide, in line with the increase in obesity prevalence. Taken into consideration the low compliance rates to continuous positive airway pressure (CPAP) treatment, and since obesity is a risk factor for OSA, these patients should receive additional counseling for weight loss through a diet plan. The aim of this review is to examine the role of a structured diet management plan on OSA severity, nocturnal oxygen indices, and subjective sleep parameters. RECENT FINDINGS Τhis systematic review of the literature resulted in four studies and demonstrated that severity of OSA, assessed by the apnea-hypopnea index, is reduced by a dietary management plan when delivered through an educational program. Moreover, nocturnal oxygenation is improved, as well as subjective sleep parameters, when initiating a diet on top of CPAP use. In summary, the present systematic review reports on the beneficial effects of a structured diet management plan in patients with OSA. Although CPAP remains the gold standard of OSA treatment, a specific dietary plan should be sought when managing patients with OSA. Nevertheless, still the evidence is low, and further research on this field is needed to reduce the burden of OSA.
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Affiliation(s)
- Aikaterini Rokou
- Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Anna Eleftheriou
- Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Christina Tsigalou
- Laboratory of Microbiology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Ioulianos Apessos
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, Dragana, 68100, Alexandroupolis, Greece
| | - Evangelia Nena
- Laboratory of Social Medicine, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Maria Dalamaga
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Athanasios Voulgaris
- Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, Dragana, 68100, Alexandroupolis, Greece.
| | - Paschalis Steiropoulos
- Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, Dragana, 68100, Alexandroupolis, Greece
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Czerwaty K, Dżaman K, Sobczyk KM, Sikorska KI. The Overlap Syndrome of Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease: A Systematic Review. Biomedicines 2022; 11:biomedicines11010016. [PMID: 36672523 PMCID: PMC9856172 DOI: 10.3390/biomedicines11010016] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/08/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) are common diseases that strongly impact the quality and length of life. Their coexistence is determined by overlap syndrome (OS). This systematic review aims to define the significance of these comorbidities according to the current state of knowledge. For this systematic review, we searched PubMed, Scopus, and Cochrane for studies published between 2018 and 26 October 2022, to find original, observational, human studies published in English, where the diagnosis of COPD was according to the Global Initiative for Obstructive Lung Disease guidelines and the diagnosis of OSA was based on polysomnography. The quality of studies was assessed using the Newcastle-Ottawa quality assessment tool for cohort and case-control studies, as well as its modification for cross-sectional studies. Of the 1548 records identified, 38 were eligible and included in this systematic review. The included studies covered a total population of 27,064 participants. This paper summarizes the most important, up-to-date information regarding OS, including the prevalence, meaning of age/gender/body mass index, polysomnography findings, pulmonary function, comorbidities, predicting OSA among COPD patients, and treatment of this syndrome.
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Archontogeorgis K, Voulgaris A, Nena E, Zissimopoulos A, Bouloukaki I, Schiza SE, Steiropoulos P. Vitamin D Levels in Patients with Overlap Syndrome, Is It Associated with Disease Severity? J Pers Med 2022; 12:jpm12101693. [PMID: 36294836 PMCID: PMC9605178 DOI: 10.3390/jpm12101693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/03/2022] [Accepted: 10/06/2022] [Indexed: 11/16/2022] Open
Abstract
Background: The coexistence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) has been defined as overlap syndrome (OVS). Recently, a link between OSA, COPD and Vitamin D (Vit D) serum concentration was reported, however, evidence regarding Vit D status in patients with OVS is scarce. The aim of the present study was to evaluate Vit D serum levels and to explore the association of those levels with anthropometric, pulmonary function and sleep parameters in patients with OVS. Methods: Vit D serum levels were measured in patients diagnosed with OVS, as confirmed by overnight polysomnography and pulmonary function testing. Results: A total of 90 patients (79 males and 11 females) were included in the analysis. The patients were divided into three groups matched for age, gender, and BMI: the control group that included 30 patients (27 males and 3 females), the OSA group that included 30 patients (26 males and 4 females), and the OVS group that included 30 patients (26 males and 4 females). Patients with OVS exhibited decreased serum 25(OH)D levels compared with OSA patients and controls (14.5 vs. 18.6 vs. 21.6 ng/mL, p < 0.001). In the OVS group, multiple linear regression analysis identified AHI and FEV1, as predictors of serum 25(OH)D levels (p = 0.041 and p = 0.038, respectively). Conclusions: Lower Vit D levels have been observed in patients with OVS compared with OSA patients and non-apneic controls, indicating an increased risk of hypovitaminosis D in this population which might be associated with disease severity.
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Affiliation(s)
- Kostas Archontogeorgis
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Athanasios Voulgaris
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Evangelia Nena
- Laboratory of Social Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Athanasios Zissimopoulos
- Laboratory of Nuclear Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Izolde Bouloukaki
- Sleep Disorders Unit, Department of Respiratory Medicine, Medical School, University of Crete, 71110 Heraklion, Greece
| | - Sophia E. Schiza
- Sleep Disorders Unit, Department of Respiratory Medicine, Medical School, University of Crete, 71110 Heraklion, Greece
| | - Paschalis Steiropoulos
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
- Correspondence: ; Tel.: +30-551352096
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Liu W, Guo H, Ding F, Cui Z, Zhang J, Wang J, Yuan Y. Comparison of invasive intubation and noninvasive mechanical ventilation in patients with chronic obstructive pulmonary disease and obstructive sleep apnoea syndrome. J Int Med Res 2021; 49:3000605211068312. [PMID: 34939869 PMCID: PMC8721719 DOI: 10.1177/03000605211068312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective The concurrence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnoea syndrome (OSAS) is defined as overlap syndrome (OS), but investigations into predictors of OS in patients with COPD remain limited. Here, potential markers of OS in patients with COPD were investigated, and results of intubation were compared between patients with COPD only or OS. Methods This retrospective study included patients with COPD who were divided according to OS diagnosis: COPD only (COPD group) or OS (OS group). Results Among 206 patients with COPD, 120 were diagnosed with OS. Mean body mass index (BMI) was significantly higher in the OS versus COPD group (28.95 ± 2.96 versus 23.84 ± 4.06, respectively). Receiver operating characteristic curve analyses revealed that BMI was associated with OS (area under the curve, 0.835). The rate of invasive intubation within 48 h was lower in the OS versus COPD group (9.2% versus 20.9%, respectively), and the duration of noninvasive ventilation was longer in the OS versus COPD group. Conclusions BMI may be a predictor of OS in patients with COPD. The duration of noninvasive ventilation was longer in patients with OS than in patients with COPD alone.
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Affiliation(s)
- Wenjing Liu
- Second Department of Respiratory and Critical Care Medicine, The Second Hospital of Hebei Medical University, Shijiazhuang, China.,Department of Respiratory and Critical Care Medicine, Harrison International Peace Hospital Affiliated to Hebei Medical University, Hengshui, China
| | - Hong Guo
- Department of Neurosurgery, Harrison International Peace Hospital Affiliated to Hebei Medical University, Hengshui, China
| | - Fang Ding
- Department of Gerontology, Harrison International Peace Hospital Affiliated to Hebei Medical University, Hengshui, China
| | - Zhaobo Cui
- Department of Respiratory and Critical Care Medicine, Harrison International Peace Hospital Affiliated to Hebei Medical University, Hengshui, China
| | - Juxiang Zhang
- Department of Respiratory and Critical Care Medicine, Harrison International Peace Hospital Affiliated to Hebei Medical University, Hengshui, China
| | - Jing Wang
- Department of Respiratory and Critical Care Medicine, Harrison International Peace Hospital Affiliated to Hebei Medical University, Hengshui, China
| | - Yadong Yuan
- Second Department of Respiratory and Critical Care Medicine, The Second Hospital of Hebei Medical University, Shijiazhuang, China
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Tang M, Wang Y, Wang M, Tong R, Shi T. Risk for Cardiovascular Disease and One-Year Mortality in Patients With Chronic Obstructive Pulmonary Disease and Obstructive Sleep Apnea Syndrome Overlap Syndrome. Front Pharmacol 2021; 12:767982. [PMID: 34764876 PMCID: PMC8576345 DOI: 10.3389/fphar.2021.767982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 10/04/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Patients with chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSAS) overlap syndrome (OS) are thought to be at increased risk for cardiovascular diseases. Objective: To evaluate the burden of cardiovascular diseases and long-term outcomes in patients with OS. Methods: This was a retrospective cohort study. The prevalence of cardiovascular diseases and 1-year mortality were compared among patients diagnosed with OS (OS group), COPD alone (COPD group) and OSAS alone (OSAS group), and Cox proportional hazards models were used to assess independent risk factors for all-cause mortality. Results: Overall, patients with OS were at higher risk for pulmonary hypertension (PH), heart failure and all-cause mortality than patients with COPD or OSAS (all p < 0.05). In multivariate Cox regression analysis, the Charlson comorbidity index (CCI) score [adjusted hazard ratio (aHR): 1.273 (1.050–1.543); p = 0.014], hypertension [aHR: 2.006 (1.005–4.004); p = 0.048], pulmonary thromboembolism (PTE) [aHR: 4.774 (1.335–17.079); p = 0.016] and heart failure [aHR: 3.067 (1.521–6.185); p = 0.002] were found to be independent risk factors for 1-year all-cause mortality. Conclusion: Patients with OS had an increased risk for cardiovascular diseases and 1-year mortality. More efforts are needed to identify the causal relationship between OS and cardiovascular diseases, promoting risk stratification and the management of these patients.
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Affiliation(s)
- Manyun Tang
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Yidan Wang
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Mengjie Wang
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Rui Tong
- Department of Geriatric Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Tao Shi
- Department of Cardiovascular Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
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Voulgaris A, Archontogeorgis K, Pataka A, Flaris AN, Ntolios P, Bonsignore MR, Schiza S, Steiropoulos P. Burden of Comorbidities in Patients with OSAS and COPD-OSAS Overlap Syndrome. Medicina (B Aires) 2021; 57:medicina57111201. [PMID: 34833419 PMCID: PMC8623094 DOI: 10.3390/medicina57111201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/23/2021] [Accepted: 11/01/2021] [Indexed: 01/10/2023] Open
Abstract
Background and Objectives: Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are usually associated with multi-morbidity. The aim of this study was to retrospectively investigate the prevalence of comorbidities in a cohort of patients with OSAS and COPD-OSAS overlap syndrome (OS) patients and to explore differences between these two groups. Materials and Methods: Included were consecutive OS patients and OSAS patients who had been referred to our sleep laboratory, and were matched in terms of sex, age, BMI, and smoking history. Presence of comorbidities was recorded based on their medical history and after clinical and laboratory examination. Results: The two groups, OS patients (n = 163, AHI > 5/h and FEV1/FVC < 0.7) and OSAS patients (n = 163, AHI > 5/h, and FEV1/FVC > 0.7), did not differ in terms of apnea hypopnea index (p = 0.346), and oxygen desaturation index (p = 0.668). Compared to OSAS patients, OS patients had lower average SpO2 (p = 0.008) and higher sleep time with oxygen saturation <90% (p = 0.002) during sleep, and lower PaO2 (p < 0.001) and higher PaCO2 (p = 0.04) in wakefulness. Arterial hypertension was the most prevalent comorbidity for both OS and OSAS, followed by dyslipidemia, cardiovascular disease (CVD) and diabetes. OS was characterized by a higher prevalence of total comorbidities (median (IQR):2 (1–3) vs. 2 (1–2), p = 0.033), which was due to the higher prevalence of CVD (p = 0.016) than OSAS. No differences were observed in other comorbidities. Conclusions: In OS patients, nocturnal hypoxia and impaired gas exchange in wakefulness are more overt, while a higher burden of CVD is observed among them in comparison to sex-, age- and BMI-matched OSAS patients.
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Affiliation(s)
- Athanasios Voulgaris
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (K.A.); (P.S.)
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
- Correspondence: ; Tel.: +30-2551030377; Fax: +30-2551352096
| | - Kostas Archontogeorgis
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (K.A.); (P.S.)
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Athanasia Pataka
- Respiratory Failure Unit, George Papanikolaou General Hospital, Aristotle University, 57010 Thessaloniki, Greece;
| | - Alexandros N. Flaris
- Department of Surgery, Tulane University, School of Medicine, New Orleans, LA 70112, USA;
| | - Paschalis Ntolios
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
| | - Maria R. Bonsignore
- Institute of Biomedicine and Molecular Immunology, National Research Council (CNR), 90146 Palermo, Italy;
- Biomedical Department of Internal and Specialistic Medicine (DIBIMIS), University of Palermo, 90133 Palermo, Italy
| | - Sophia Schiza
- Sleep Disorders Unit, Department of Respiratory Medicine, Medical School, University of Crete, 71500 Heraklion, Greece;
| | - Paschalis Steiropoulos
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece; (K.A.); (P.S.)
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece;
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11
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Yang CC, Lee KW, Watanabe K, Kawakami N. The association between shift work and possible obstructive sleep apnea: a systematic review and meta-analysis. Int Arch Occup Environ Health 2021; 94:1763-1772. [PMID: 33677677 PMCID: PMC8490216 DOI: 10.1007/s00420-021-01675-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 02/16/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND Shift work is a workschedule, since industrial era and some employees work in shift. It causes a desynchronization of the biological clock with consequences on sleep amount and quality, such as insomnia and easy fatigue. Obstructive sleep apnea (OSA) is one of the sleep problems that are getting more and more attention, but studies on the association between shift work and OSA were rare. Herein, we aimed to conduct a systematic review and meta-analysis to investigate the association between shift work and possible OSA. METHODS This study was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We queried PubMed, Embase, and Web of Science databases using a related set of keywords. The inclusion criteria were as follows: (1) participants were adult employees hired by a company or organization; (2) exposure was shift work; and (3) outcome was possible OSA according to examination or assessment. RESULTS We included six studies in the systematic review and five studies were selected for further meta-analysis. A random-effects model showed an association of shift work with a small, non-significant increase in possible OSA cases (pooled prevalence relative risk = 1.05; 95% CI 0.85-1.30; p = 0.65). This association occurred in both healthcare and non-healthcare workers group. CONCLUSION The association between shift work and possible OSA remains inconclusive and could be small if not negligible. Future studies should assess the association between specific work schedules and specific OSA definitions. TRIAL REGISTRATION NUMBER PROSPERO ID: CRD42020156837.
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Affiliation(s)
- Chen-Cheng Yang
- Department of Occupational and Environmental Medicine, Kaohsiung Municipal Siaogang Hospital, No. 482, Shanming Road, Siaogang District, Kaohsiung City, Taiwan.
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
- Department of Family Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung, Taiwan.
- Department of Occupational and Environmental Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
- Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
- Environmental and Occupational Medicine Center, Kaohsiung Municipal Siaogang Hospital, Kaohsiung, Taiwan.
| | - Kuo-Wei Lee
- Department of Neurology, Kaohsiung Municipal Siaogang Hospital, Kaohsiung, Taiwan
| | - Kazuhiro Watanabe
- Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Norito Kawakami
- Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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12
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Lurie A, Roche N. Obstructive Sleep Apnea in Patients with Chronic Obstructive Pulmonary Disease: Facts and Perspectives. COPD 2021; 18:700-712. [PMID: 34595967 DOI: 10.1080/15412555.2021.1950663] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The co-occurrence of obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) in the same patient, named the overlap syndrome (OS), was first described in 1985. Although the American Thoracic Society underlined the limited knowledge of OS, stated research priorities for this condition, and recommended a "screening" strategy to identify OSA in COPD patients with chronic stable hypercapnia, research studies on OS remain scarce. This review aims to summarize the current knowledge and perspectives related to OSA in COPD patients. OS prevalence is 1.0-3.6% in the general population, 3-66% in COPD patients, and 7-55% in OSA patients. OS patients may have worse sleep quality than those with OSA or COPD alone. Scoring hypopneas may be difficult in COPD patients; desaturation episodes may have origins in these patients, namely upper airway obstruction, hypoventilation during paradoxical sleep, ventilation/perfusion mismatches, and obesity. The apnea-hypopnea index is similar in OSA and OS patients. Desaturations may be greater and more prolonged in OS patients than in patients with COPD or OSA alone. Low body mass index, hyperinflation, and less collapsible airways reduce the risk of OSA in COPD patients. OSA is a risk factor for pulmonary hypertension in COPD patients. Whether OS increases mortality and morbidity risks compared to COPD or OSA alone remains to be confirmed. No guidelines currently recommend specific approaches to the treatment of OSA in patients with COPD.
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Affiliation(s)
- Alain Lurie
- Clinique Ambroise Paré, Laboratoire du sommeil, Neuilly-sur-Seine, France.,Hôpital Cochin (AP-HP Centre), Pneumologie, Paris, France
| | - Nicolas Roche
- Hôpital Cochin (AP-HP Centre), Pneumologie, Université de Paris (Descartes), UMR 1016, Institut Cochin, Paris, France
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13
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Manolis TA, Manolis AA, Apostolopoulos EJ, Melita H, Manolis AS. Cardiovascular Complications of Sleep Disorders: A Better Night's Sleep for a Healthier Heart / From Bench to Bedside. Curr Vasc Pharmacol 2021; 19:210-232. [PMID: 32209044 DOI: 10.2174/1570161118666200325102411] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/26/2020] [Accepted: 02/26/2020] [Indexed: 12/27/2022]
Abstract
Sleep is essential to and an integral part of life and when lacking or disrupted, a multitude of mental and physical pathologies ensue, including cardiovascular (CV) disease, which increases health care costs. Several prospective studies and meta-analyses show that insomnia, short (<7h) or long (>9h) sleep and other sleep disorders are associated with an increased risk of hypertension, metabolic syndrome, myocardial infarction, heart failure, arrhythmias, CV disease risk and/or mortality. The mechanisms by which insomnia and other sleep disorders lead to increased CV risk may encompass inflammatory, immunological, neuro-autonomic, endocrinological, genetic and microbiome perturbations. Guidelines are emerging that recommend a target of >7 h of sleep for all adults >18 years for optimal CV health. Treatment of sleep disorders includes cognitive-behavioral therapy considered the mainstay of non-pharmacologic management of chronic insomnia, and drug treatment with benzodiazepine receptor agonists binding to gamma aminobutyric acid type A (benzodiazepine and non-benzodiazepine agents) and some antidepressants. However, observational studies and meta-analyses indicate an increased mortality risk of anxiolytics and hypnotics, although bias may be involved due to confounding and high heterogeneity in these studies. Nevertheless, it seems that the risk incurred by the non-benzodiazepine hypnotic agents (Z drugs) may be relatively less than the risk of anxiolytics, with evidence indicating that at least one of these agents, zolpidem, may even confer a lower risk of mortality in adjusted models. All these issues are herein reviewed.
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14
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Voulgaris A, Steiropoulos P. Coexistent obstructive sleep apnea in patients with chronic obstructive pulmonary disease: Several unanswered questions need to be addressed. Lung India 2021; 38:191-192. [PMID: 33687016 PMCID: PMC8098899 DOI: 10.4103/lungindia.lungindia_580_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Athanasios Voulgaris
- Department of Pulmonology, Medical School, University General Hospital of Alexandroupolis, Democritus University of Thrace, Alexandroupolis, Greece
| | - Paschalis Steiropoulos
- Department of Pulmonology, Medical School, University General Hospital of Alexandroupolis, Democritus University of Thrace, Alexandroupolis, Greece
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15
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Li X, He J. The Association Between Serum/Plasma Leptin Levels and Obstructive Sleep Apnea Syndrome: A Meta-Analysis and Meta-Regression. Front Endocrinol (Lausanne) 2021; 12:696418. [PMID: 34671315 PMCID: PMC8522441 DOI: 10.3389/fendo.2021.696418] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 09/07/2021] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Obstructive sleep apnea syndrome (OSAS) is associated with various adipokines. Leptin, a common adipokine, has attracted considerable attention of many researchers in recent years. So far, there has been little agreement on whether blood leptin levels differ in patients with OSAS. Thus, this meta-analysis examined the relationship between serum/plasma leptin levels and the occurrence of OSAS. METHOD WanFang, Embase, CNKI, Medline, SinoMed, Web of Science, and PubMed were searched for articles before March 30, 2021, with no language limitations. STATA version 11.0 and R software version 3.6.1 were used to analyze the obtained data. The weighted mean difference and correlation coefficients were used as the main effect sizes with a random-effects model and a fixed-effects model, respectively. Trial sequential analysis was conducted using dedicated software. RESULT Screening of 34 publications identified 45 studies that met the inclusion criteria of this meta-analysis and meta-regression. Our results suggested that plasma/serum leptin levels were remarkably higher in individuals with OSAS than in healthy individuals. Subgroup analyses were performed based on OSAS severity, ethnicity, age, body mass index, assay type, and sample source. The serum and plasma leptin levels were increased in nearly all OSAS subgroups compared to those in the corresponding control groups. Meta-regression analysis indicated that age, BMI, severity, assay approaches, study design, PSG type and ethnicity did not have independent effect on leptin levels. Furthermore, a positive relationship between the serum/plasma leptin level and apnea-hypopnea index (AHI) was found in the meta-analysis. The results of the trial sequential analysis suggested that the enrolled studies surpassed the required information size, confirming that our study findings were reliable. CONCLUSION Our study results demonstrate that OSAS patients have higher leptin levels in serum/plasma compared to controls, and the serum/plasma leptin level is positively correlated with AHI, especially in adults.
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Affiliation(s)
- Xiaoyan Li
- Department of endocrinology, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Jie He
- Department of Pulmonary and Critical Care Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
- *Correspondence: Jie He,
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16
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Metabolic Syndrome and Abnormal Peri-Organ or Intra-Organ Fat (APIFat) Deposition in Chronic Obstructive Pulmonary Disease: An Overview. Metabolites 2020; 10:metabo10110465. [PMID: 33203192 PMCID: PMC7696438 DOI: 10.3390/metabo10110465] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 11/04/2020] [Accepted: 11/13/2020] [Indexed: 12/11/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a common disorder with an increasing prevalence, characterised by persistent respiratory symptoms and airflow limitation. Systemic inflammation is involved in the pathogenesis of COPD and can also predispose to metabolic disorders (e.g., metabolic syndrome (MetS) and non-alcoholic fatty liver disease (NAFLD)). Such comorbidities can negatively affect COPD outcomes, cardiovascular risk, and quality of life. Apart from NAFLD, abnormal peri-organ or intra-organ fat (APIFat) could be considered as markers for cardiometabolic diseases and even for COPD. The present narrative review considers the associations of COPD with MetS, NAFLD, and other APIFat, including epicardial, perirenal, peripancreatic, and intramuscular adipose tissue. Further research is needed to define these relationships and identify any potential clinical implications.
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17
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Archontogeorgis K, Voulgaris A, Papanas N, Nena E, Xanthoudaki M, Pataka A, Schiza S, Rizzo M, Froudarakis ME, Steiropoulos P. Metabolic Syndrome in Patients with Coexistent Obstructive Sleep Apnea Syndrome and Chronic Obstructive Pulmonary Disease (Overlap Syndrome). Metab Syndr Relat Disord 2020; 18:296-301. [PMID: 32379990 DOI: 10.1089/met.2019.0126] [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: 01/04/2023] Open
Abstract
Background: Evidence suggests that metabolic syndrome (MetS) is highly prevalent in patients with obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD). However, data on the prevalence of MetS in patients having both OSAS and COPD, or overlap syndrome (OS), are scarce. The aim of this study was to evaluate the prevalence and identify predictors of MetS in patients with OS. Methods: MetS was evaluated in consecutive patients who were diagnosed with OS by polysomnography and pulmonary function testing. Results: A total of 163 subjects (138 males and 25 females) were included. MetS was present in 38% of OS patients. Patients were divided into group A (OS without MetS group: 101 patients) and group B (OS with MetS group: 62 patients). Groups were similar in terms of pulmonary function and sleep parameters. In group B, abdominal obesity was the most prevalent component of MetS (100%), followed by hypertension (82.3%), hypertriglyceridemia (72.6%), and hyperglycemia (51.6%). Age (P = 0.009) and body mass index (P = 0.029) were independent predictors of MetS in patients with OS. Conclusions: An increased prevalence of MetS was observed in a group of patients with OS. Early identification and treatment of MetS may play a significant role in prevention of complications related to OS.
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Affiliation(s)
- Kostas Archontogeorgis
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Athanasios Voulgaris
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.,Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Nikolaos Papanas
- Second Department of Internal Medicine, and Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Evangelia Nena
- Laboratory of Hygiene and Environmental Protection, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Maria Xanthoudaki
- Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Athanasia Pataka
- Respiratory Failure Unit, G. Papanikolaou General Hospital, Aristotle University, Thessaloniki, Greece
| | - Sophia Schiza
- Sleep Disorders Unit, Department of Respiratory Medicine, Medical School, University of Crete, Heraklion, Greece
| | - Manfredi Rizzo
- Biomedical Department of Internal Medicine and Medical Specialties School of Medicine, University of Palermo, Palermo, Italy.,Division of Endocrinology, Diabetes and Metabolism, University of South Carolina, School of Medicine Columbia, Columbia, South Carolina, USA
| | - Marios E Froudarakis
- Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
| | - Paschalis Steiropoulos
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.,Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece
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