Depression is characterized by prolonged feelings of sadness. You are considered clinically depressed if there is no obvious cause for your sadness or withdrawal or your reaction to life’s circumstances is exaggerated or prolonged.
Recent research has shown that sleep apnea can lead to depression. While some people report that symptoms of both conditions occurred simultaneously, others experience sleep deprivation/apnea before the symptoms of depression appear. Either condition can increase your risk factor for the other.