What is "obesity hypoventilation syndrome"

n. (context medicine English) A condition in which a severely overweight person fails to breathe rapidly or deeply enough, resulting in low blood oxygen levels and high blood carbon dioxide levels.

Obesity hypoventilation syndrome (also known as Pickwickian syndrome) is a condition in which severely overweight people fail to breathe rapidly enough or deeply enough, resulting in low blood oxygen levels and high blood carbon dioxide (CO) levels. Many people with this condition also frequently stop breathing altogether for short periods of time during sleep ( obstructive sleep apnea), resulting in many partial awakenings during the night, which leads to continual sleepiness during the day. The disease puts strain on the heart, which eventually may lead to the symptoms such as heart failure, leg swelling and various other related symptoms. The most effective treatment is weight loss, but it is often possible to relieve the symptoms by nocturnal ventilation with positive airway pressure (CPAP) or related methods.

Obesity hypoventilation syndrome is defined as the combination of obesity ( body mass index above 30 kg/m), hypoxemia (falling oxygen levels in blood) during sleep, and hypercapnia (increased blood carbon dioxide levels) during the day, resulting from hypoventilation (excessively slow or shallow breathing). The disease has been known since the 1950s, initially as "Pickwickian syndrome" in reference to a Dickensian character but currently under a more descriptive name.