Definition:

Obesity hypoventilation syndrome (OHS) is defined as the triad of obesity (BMI of 30 or higher), daytime hypoventilation, and sleep-disordered breathing in the absence of any other cause of hypoventilation. The features include marked obesity, somnolence, twitching, cyanosis, periodic respiration, polycythemia, and right ventricular hypertrophy and failure. Patients with untreated OHS have a significant risk of death. While continuous positive airway pressure (CPAP) treatments may temporize cardiopulmonary disease progression, simultaneous pursuit of weight reduction is central to long-term management of this condition.