Excessive Sleepiness in OSA: Is it more then an Airway Problem?

Areas of brain with reduced gray matter assoc. with OSA

Chronic Obstructive Sleep Apnea may lead to neurological damage that may cause persistent fatigue even after corrective treatment.

In a study by Joo EY Tae/ Sleep, it showed brain damage to the areas thought to be responsible for wakefulness. These particular regions are quite sensitive to low levels of oxygen and can be damaged as a result of chronic Obstructive Sleep Apnea. This injury is thought to be reversible but when it is not, it may explain why some people remain fatigued despite proper treatment.

Patients with persistent fatigue despite the use of CPAP were examined and found to have changes in their brain’s white mater.

In these patients, the fibers in the brain responsible for producing the wake promoting chemicals were reduced despite corrective treatment with CPAP. This may be a factor in patients with chronic residue fatigue.

Selected fiber tracts show changes in white matter in patients with sleepiness

A study by Zhu in Frontal Neurol showed neurological damage lasting 4 weeks in laboratory mice. 25% of the wake promoting neural fibers remained diminished despite a return to normal sleep.


Excessive Sleepiness is a common symptom in patients with Obstructive Sleep Apnea. Sometimes, despite treatment; the fatigue remains. Studies suggest that in certain cases, it may be do to residual neurologic damage to the wake promoting fibers. Fortunately, medications are available to help in these conditions.

Richard Hamburg MD, DDS