Obesity Hypoventilation Syndrome

**Definition:** HYPOVENTILATION syndrome in very obese persons with excessive ADIPOSE TISSUE around the ABDOMEN and DIAPHRAGM. It is characterized by diminished to absent ventilatory chemoresponsiveness; chronic HYPOXIA; HYPERCAPNIA; POLYCYTHEMIA; and long periods of sleep during day and night (HYPERSOMNOLENCE). It is a condition often related to OBSTRUCTIVE SLEEP APNEA but can occur separately.

**Tree numbers:** - C08.618.085.852.850.500 - C08.618.846.565.500 - C10.886.425.800.750.850.500 - C18.654.726.750.500.600

**Synonyms:** - Pickwickian Syndrome - Obesity-Hypoventilation Syndrome