Considerable evidence is available in support of an independent association between obstructive sleep apnoea syndrome (OSAS) and cardiovascular disease, which is particularly strong for systemic arterial hypertension and growing for ischaemic heart disease, stroke, heart failure, atrial fibrillation and cardiac sudden death. The pathogenesis of cardiovascular disease in OSAS is not completely understood but likely to be multifactorial, involving a diverse range of mechanisms including sympathetic nervous system overactivity, selective activation of inflammatory molecular pathways, endothelial dysfunction, abnormal coagulation and metabolic dysregulation, the latter particularly involving insulin resistance and disordered lipid metabolism. The present report, which arose out of a European Union Cooperation in the field of Scientific and Technical Research (COST) action on OSAS (COST B26), reviews the current evidence for an independent association and proposes research priorities to identify the underlying mechanisms involved, with a view to identifying novel therapeutic strategies. Large-scale collaborative studies of carefully defined patient populations with obstructive sleep apnoea syndrome, adequately controlled for potential confounders, are needed. Such studies carry the prospect of evaluating potential interactions between different basic mechanisms operating in obstructive sleep apnoea syndrome and cardiovascular disease, and interactions with other related disorders, such as obesity, diabetes and dyslipidaemia. Furthermore, translational studies involving cell culture and animal models linked to studies of obstructive sleep apnoea syndrome patients are necessary to integrate basic mechanisms with the clinical disorder.

https://erj.ersjournals.com/content/erj/29/1/156.full.pdf

Sleep apnoea as an independent risk factor for cardiovascular disease: current evidence, basic mechanisms and research priorities

Obesity and its repercussions constitute an important source of morbidity, impaired quality of life and its complications can have a major bearing on life expectancy. The present article summarizes the most important co-morbidities of obesity and their prevalence. Furthermore, it describes classification and grading systems that can be used to assess the individual and combined impact of co-morbid conditions on mortality risk. The literature was screened for assessment tools that can be deployed in the quantification of morbidity and mortality risk in individual patients. Thirteen specific domains have been identified that account for morbidity and mortality in obesity. Cardiovascular disease (CVD) and cancer account for the greatest mortality risk associated with obesity. The King’s Criteria and Edmonton Obesity Staging System (EOSS) were identified as useful tools for the detection and monitoring of individual patient mortality risk in obesity care. The stark facts on the complications of obesity should be capitalized on to improve patient management and knowledge and referred to in the wider dissemination of public health messages aimed at improving primary prevention.

Morbidity and mortality associated with obesity.

According to the 36-Item Short Form Health Survey questionnaire developers, a global measure of health-related quality of life such as the "SF-36 Total/Global/Overall Score" cannot be generated from the questionnaire. However, studies keep on reporting such measure. This study aimed to evaluate the frequency and to describe some characteristics of articles reporting the SF-36 Total/Global/Overall Score in the scientific literature. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses method was adapted to a scoping review. We performed searches in PubMed, Web of Science, SCOPUS, BVS, and Cochrane Library databases for articles using such scores. We found 172 articles published between 1997 and 2015; 110 (64.0%) of them were published from 2010 onwards; 30.0% appeared in journals with Impact Factor 3.00 or greater. Overall, 129 (75.0%) out of the 172 studies did not specify the method for calculating the "SF-36 Total Score"; 13 studies did not specify their methods but referred to the SF-36 developers' studies or others; and 30 articles used different strategies for calculating such score, the most frequent being arithmetic averaging of the eight SF-36 domains scores. We concluded that the "SF-36 Total/Global/Overall Score" has been increasingly reported in the scientific literature. Researchers should be aware of this procedure and of its possible impacts upon human health.

https://journals.sagepub.com/doi/pdf/10.1177/2050312116671725

SF-36 total score as a single measure of health-related quality of life: Scoping review:

Anxiety and depression in COPD patients: The roles of gender and disease severity.

Obesity and obstructive sleep apnea tend to coexist and are associated with inflammation, insulin resistance, dyslipidemia, and high blood pressure, but their causal relation to these abnormalities is unclear. Methods We randomly assigned 181 patients with obesity, moderate-to-severe obstructive sleep apnea, and serum levels of C-reactive protein (CRP) greater than 1.0 mg per liter to receive treatment with continuous positive airway pressure (CPAP), a weight-loss intervention, or CPAP plus a weight-loss intervention for 24 weeks. We assessed the incremental effect of the combined interventions over each one alone on the CRP level (the primary end point), insulin sensitivity, lipid levels, and blood pressure. Results Among the 146 participants for whom there were follow-up data, those assigned to weight loss only and those assigned to the combined interventions had reductions in CRP levels, insulin resistance, and serum triglyceride levels. None of these changes were observed in the group receiving CPAP alone. Blood pressure was reduced in all three groups. No significant incremental effect on CRP levels was found for the combined interventions as compared with either weight loss or CPAP alone. Reductions in insulin resistance and serum triglyceride levels were greater in the combined-intervention group than in the group receiving CPAP only, but there were no significant differences in these values between the combined-intervention group and the weight-loss group. In per-protocol analyses, which included 90 participants who met prespecified criteria for adherence, the combined interventions resulted in a larger reduction in systolic blood pressure and mean arterial pressure than did either CPAP or weight loss alone. Conclusions In adults with obesity and obstructive sleep apnea, CPAP combined with a weightloss intervention did not reduce CRP levels more than either intervention alone. In secondary analyses, weight loss provided an incremental reduction in insulin resistance and serum triglyceride levels when combined with CPAP. In addition, adherence to a regimen of weight loss and CPAP may result in incremental reductions in blood pressure as compared with either intervention alone. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT0371293.)

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CPAP, Weight Loss, or Both for Obstructive Sleep Apnea

Relationship Between Quality of Life and Mood or Depression in Patients With Severe Obstructive Sleep Apnea Syndrome

Objective To assess changes in response to nasal continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea syndrome (OSAS) concerning excessive daytime sleepiness (EDS), depressive state, and quality of life (QOL)Patients and Methods We assessed for EDS using the Epworth sleepiness scale (ESS), for mood using The Zung self-depression scale (SDS), and for QOL using Short-Form 36 (SF-36) in 132 patients with obstructive sleep apnea syndrome (OSAS) and control subjects Patients had severe OSAS (apnea-hypopnea index, 594±238/h) and were more hypersomnolent and depressed, and had poorer QOL than 38 age- and gender-matched controlsResults Before treatment most QOL domains in the SF-36 were significantly associated with patients’ SDS scores With nasal CPAP, ESS and SDS scores were respectively decreased from 97±45 to 40±24 (p<00001) and from 492±104 to 451±96 (p<00005) Total SF-36 score and scores for seven of eight domains were increased significantly with treatment Thus, nasal CPAP lessens EDS and depression, and improves QOL, in patients with severe OSAS Further, magnitudes of changes in total SF-36 scores and in five of eight domains correlated significantly with magnitude of change in SDS score upon nasal CPAP treatment No relationship was evident between treatment-associated score changes in SF-36 domains and ESS score changeConclusion Although patients with severe OSAS have poorer QOL than control subjects, nasal CPAP appears to improve QOL by alleviating depression

/pdf/nasal-cpap-improves-the-quality-of-life-and-lessens-the-k2fz3mkhs8.pdf

Nasal CPAP improves the quality of life and lessens the depressive symptoms in patients with obstructive sleep apnea syndrome.

Objective: To clarify the prevalence and clinical characteristics of obesity-hypoventilation syndrome (OHS) in a large number of patients with moderate to severe obstructive sleep apnea syndrome (OSAS). Methods: Subjects comprised 611 patients with OSAS registered from 7 sleep centers and clinics and analyzed according to the definitions of the Respiratory Failure Research Group of the Japanese Ministry of Health and Welfare. Baseline characteristics, polysomnographic data during sleep, laboratory blood examinations, excessive daytime sleepiness, pulmonary functions, and arterial blood gases were compared between OHS and non-OHS patients. Determinants of daytime hypercapnia were also examined in OHS patients. Results: OHS was identified in 55 of the 611 patients with OSAS (9%). OHS patients were younger, heavier, and more somnolent than non-OHS patients and displayed more severe OSAS, liver dysfunctions, higher total cholesterol, and impaired pulmonary function. However, these differences were resolved except for pulmonary function after correction for obesity. Daytime hypercapnia was associated with impaired pulmonary function. Percent vital capacity (%VC) was most closely correlated with PaCO2 in OHS. Conclusion: OHS patients display numerous abnormalities due to obesity compared with non-OHS patients. Impaired pulmonary function, particularly %VC, may play an important role in the development of daytime hypercapnia independent of obesity in OHS patients.

Clinical characteristics of obesity-hypoventilation syndrome in Japan: a multi-center study.

Determinants of chronic hypercapnia in Japanese men with obstructive sleep apnea syndrome.

Serum levels of C-reactive protein (CRP) were measured in 96 consecutive patients with obstructive sleep apnea syndrome (OSAS) before and after nasal continuous positive airway pressure treatment. CRP levels only displayed significant correlations with body mass index (BMI) before treatment. No significant changes were observed in BMI and CRP levels after 9 months of treatment. These data suggest that CRP levels in patients with OSAS may be associated with obesity rather than OSAS itself.

Seiji Kawahara

Papers

Relationship Between Quality of Life and Mood or Depression in Patients With Severe Obstructive Sleep Apnea Syndrome

Nasal CPAP improves the quality of life and lessens the depressive symptoms in patients with obstructive sleep apnea syndrome.

Clinical characteristics of obesity-hypoventilation syndrome in Japan: a multi-center study.

Determinants of chronic hypercapnia in Japanese men with obstructive sleep apnea syndrome.

Effects of long-term nasal continuous positive airway pressure on C-reactive protein in patients with obstructive sleep apnea syndrome.