The relationship between asthma, sleep apnea, and other respiratory disorders and childhood metabolic syndrome

Abstract

Introduction: Obesity and the metabolic syndrome are associated with increased morbidity from chronic respiratory diseases such as asthma and sleep-disordered breathing, as well as increased risk of perioperative respiratory complications. Asthma: Asthma is the most common chronic disease of childhood, and its prevalence has risen significantly in the last few decades, in parallel with the increase in childhood obesity and metabolic syndrome. There is ever-growing evidence of an association between both, and while our understanding of this relationship far from complete, several mechanisms have been proposed. These include mechanical changes on the airways and the lungs due to excess weight, alterations in the function of airway smooth muscle, a generalized inflammatory state that induces airway inflammation and hyperreactivity, several metabolic abnormalities such as decreased vitamin D or increased oxidative stress, alterations in insulin metabolism that promotes airway remodeling, hormonal differences, and shared genetic determinants between both illnesses. Sleep-disordered breathing: This term encompasses upper airway resistance syndrome, obstructive sleep apnea (OSA), and obesity hypoventilation syndrome, all of which have been associated with obesity. Proposed mechanisms are in part similar to those mentioned for asthma, including mechanical effects of added weight in the upper airways, a systemic proinflammatory milieu, hormonal changes, and oxidative stress. As a result, these patients are also at higher risk of cardiovascular and other complications from both their obesity/metabolic syndrome and their sleep-disordered breathing. Other conditions: Patients with obesity/metabolic syndrome are also at higher risk of perioperative respiratory complications, and patients should be carefully assessed and monitored to minimize morbidity. While studies in children are lacking, obese adults are also at increased risk for acute lung injury and acute respiratory distress syndrome (ARDS), with increased length of stay and increased mortality.