Abdominal Fat and Sleep Apnea

Abstract

Obstructive sleep apnea (OSA) syndrome is a disorder characterized by repetitive episodes of upper airway obstruction that occur during sleep. Associated features include loud snoring, fragmented sleep, repetitive hypoxemia/hypercapnia, daytime sleepiness, and cardiovascular complications. The prevalence of OSA is 2-3% and 4 -5% in middle-aged women and men, respectively. The prevalence of OSA among obese patients exceeds 30%, reaching as high as 50 -98% in the morbidly obese population. Obesity is probably the most important risk factor for the development of OSA. Some 60 -90% of adults with OSA are overweight, and the relative risk of OSA in obesity (BMI Ͼ29 kg/m 2 ) is Ն10. Numerous studies have shown the development or worsening of OSA with increasing weight, as opposed to substantial improvement with weight reduction. There are several mechanisms responsible for the increased risk of OSA with obesity. These include reduced pharyngeal lumen size due to fatty tissue within the airway or in its lateral walls, decreased upper airway muscle protective force due to fatty deposits in the muscle, and reduced upper airway size secondary to mass effect of the large abdomen on the chest wall and tracheal traction. These mechanisms emphasize the great importance of fat accumulated in the abdomen and neck regions compared with the peripheral one. It is the abdomen much more than the thighs that affect the upper airway size and function. Hence, obesity is associated with increased upper airway collapsibility (even in nonapneic subjects), with dramatic improvement after weight reduction. Conversely, OSA may itself predispose individuals to worsening obesity because of sleep deprivation, daytime somnolence, and disrupted metabolism. OSA is associated with increased sympathetic activation, sleep fragmentation, ineffective sleep, and insulin resistance, potentially leading to diabetes and aggravation of obesity. Furthermore, OSA may be associated with changes in leptin, ghrelin, and orexin levels; increased appetite and caloric intake; and again exacerbating obesity. Thus, it appears that obesity and OSA form a vicious cycle where each results in worsening of the other. Diabetes Care 31 (Suppl. 2):S303-S309, 2008A lthough interest in sleep and dreams has existed since the dawn of history, it has only been in the last 25-35 years that physicians have recognized the importance of sleep disorders, and only in the last 20 -25 years that sleep laboratory services have been commonly available. Over the recent years, several categories of sleep disorders were recognized, with special interest in breathing disorders during sleep. It is quite clear now that quantity and quality of life deteriorates secondary to sleep disordered breathing, with complex associations between sleep-disordered breathing and obesity, cardiac diseases, stroke, and diabetes.Obstructive sleep apnea (OSA) syndrome is characterized by the recurrent collapse of the pharyngeal airway during sleep, which generally requires arousal to reestablish airway patency and...

Waist circumference and waist/hip ratio in relation to all-cause mortality, cancer and sleep apnea

“…Conversely, OSA may itself predispose individuals to worsening obesity because of sleep deprivation, daytime somnolence and disrupted metabolism. OSA is associated with increased sympathetic activation, sleep fragmentation, ineffective sleep and insulin resistance, potentially leading to diabetes and aggravation of obesity (Pillar and Shehadeh, 2008). The association between obesity and OSA has been noted in cross-sectional and longitudinal studies.…”

Psychometric analysis of the Three-Factor Eating Questionnaire-R21: results from a large diverse sample of obese and non-obese participants

“…Obesity is a risk factor for several diseases, such as diabetes, heart disease, fatty liver, sleep apnea and some cancers, [1][2][3] and is associated with substantial direct and indirect costs. 4 The worldwide prevalence of obesity has increased dramatically over the last decade, and there is an urgent need to better understand the eating behavior in humans and how obesity might be treated.…”

Relationship Between Obstructive Sleep Apnea and Increased Thoracic Periaortic Adipose Tissue

“…19 These informations consolidate the assumption that BMI is not a beneficial estimation factor of OSA, whether abdominal fat indices is better susceptible factor for estimation. [25][26][27] In conclusion, our findings indicate significantly higher values for thoracic periaortic adipose tissue in OSA than controls, being associated positively with AHI levels and strongly predicted by AHI levels in OSA subjects, while not differing with respect to gender and smoking status.…”