THE ROLE OF SLEEP IN THE PATHOGENESIS OF OBESITY AND OBSTRUCTIVE SLEEP APNEA IN ADULTS: A SYSTEMATIC REVIEW

Abstract

Obesity and obstructive sleep apnea (OSA) are common, clinically important and mutually reinforcing conditions associated with metabolic, cardiovascular and respiratory morbidity. Although obesity is widely recognized as a major modifiable risk factor for OSA, the relationship between sleep, weight regulation and sleep-disordered breathing is not limited to mechanical narrowing of the upper airway. The aim of this systematic review was to synthesize current evidence on the role of sleep duration, sleep quality, circadian disruption and sleep fragmentation in the pathogenesis of obesity and adult OSA. Scientific publications indexed in PubMed were reviewed, with priority given to systematic reviews, meta-analyses, prospective cohort studies, randomized controlled trials and major clinical reviews. The evidence indicates that short sleep duration is associated with future obesity and central obesity, while experimental sleep restriction promotes increased energy intake, impaired insulin sensitivity and adverse metabolic changes. Obesity contributes to OSA through upper-airway soft tissue enlargement, reduced lung volumes, increased pharyngeal collapsibility and altered ventilatory control. Conversely, OSA may worsen metabolic dysfunction through intermittent hypoxia, sleep fragmentation, sympathetic activation, oxidative stress and inflammation. These findings support a bidirectional model in which insufficient sleep, obesity and OSA interact through behavioral, endocrine, inflammatory and respiratory mechanisms. Adult patients with obesity should therefore be routinely assessed for sleep health and OSA risk, while OSA management should include weight and metabolic strategies in addition to airway-directed therapy.