Obstructive Sleep Apnea Syndrome: An Under -recognized Clinical Entity with Significant Systemic Morbidities

Obstructive sleep apnea syndrome (OSAS) is a highly prevalent yet under recognized sleep disorder, characterized by repeated disruptions of breathing during sleep. Not just merely a local phenomenon of upper respiratory tract obstruction, this has many consequences that includes intermittent hypoxia, intermittent hypercapnia, reoxygenation, intra thoracic pressure changes, sympathetic activation, micro-awakenings and sleep fragmentation leading to metabolic dysregulation, endothelial dysfunction, systemic inflammation, oxidative stress, hypercoagulation, and neurohumoral changes that causes excessive daytime sleepiness, neurocognitive deterioration, endocrine, metabolic and other systemic effects including poor quality of life. There are increasing evidences to suggest that OSAS is a systemic inflammatory disease. Epidemiological studies have identified OSAS as an independent risk factor in cardiovascular diseases, metabolic syndrome and bronchial asthma. Patho-physiological changes in OSAS are causally linked to the hypertension with increase risk for heart failure, stroke and cardiovascular mortality. In addition, OSAS is associated with several other disorders and comorbidities that may affect almost every organ systems of our body. Despite having many complex systemic consequences, OSAS and its secondary effects are mostly controllable by continuous positive air pressure (CPAP). This disorder largely remains an underestimated clinical entity due to unawareness by both the patient and physician alike. There is need for awareness regarding this entity among all specialties of medicine and surgery as the so called undetected/occult disease if remain untreated may lead to significant systemic morbidities and at times mortality.