Cystic fibrosis (CF) is a genetic disorder characterized by the production of sweat with a high salt content and mucus secretions with an abnormal viscosity.

A condition characterized by obstruction of the airway and by pauses in breathing during sleep occurring many times during the night. Obstructive sleep apnea is related to a relaxation of muscle tone (which normally occurs during sleep) leading to partial collapse of the soft tissues in the airway with resultant obstruction of the air flow.