The obesity hypoventilation syndrome.

We only need to look around us to see that we are in an epidemic of obesity and obesity-related medical problems. The obesity hypoventilation syndrome is a disorder in which an obese person with normal lungs chronically hypoventilates. Obesity impairs ventilatory mechanics, increases the work of breathing and carbon dioxide production, results in respiratory muscle dysfunction, and reduces ventilatory response to hypercapnia. Sleep-disordered breathing is present in most patients with the obesity hypoventilation syndrome. When noninvasive ventilation can be successfully introduced, hypoventilation can usually be corrected. Weight loss is the desirable long-term treatment for the obesity hypoventilation syndrome. This paper concisely overviews the physiologic factors that lead to the obesity hypoventilation syndrome and discusses therapies for it.