Symptoms:

Symptoms are usually worse during sleep, and periods of apnea (episodes of stopped breathing) are usually present. Often patients themselves do not complain of shortness of breath during the day.

Symptoms include:

• Bluish coloration of the skin caused by lack of oxygen
• Daytime drowsiness
• Fatigue
• Lethargy
• Morning headaches
• Swelling of the ankles
• Waking up from sleep unrested
• Waking up many times at night

Persons with this disease are extremely sensitive to even small doses of sedatives or narcotics, which can make their already inadequate breathing much worse.

Signs and tests:

The health care provider will perform a physical exam. Tests will be done to rule out other causes. For example, muscular dystrophy can make the rib muscles weak, and emphysema damages the lung tissue itself. A small stroke can affect the breathing center in the brain.

Tests that may be done include:

• Blood gases
• Chest x-ray
• Hematocrit and hemoglobin blood tests
• Lung function tests
• Overnight oxygen level measurements (oximetry)
• Serum bicarbonate
• Sleep study (polysomnography)