• Symptoms -- what a person with sleep apnea feels
• Signs -- what other people can see (and hear)
• Medical consequences -- health problems found in persons with sleep apnea

Sleepiness is the cardinal symptom of sleep apnea. In some cases it may be all but unnoticeable. In others, it can be incapacitating. Driving may become impossible (and dangerous). Sleep may overtake a person in the middle of a conversation. President Taft had severe sleepiness at certain times in his illness.

Persons with sleep apnea may use other words to describe the way they feel, for example "tired" or "fatigued."

The symptoms of sleep apnea can develop so gradually that a person may not realize they have become ill. When persons begin to benefit from treatment for sleep apnea, it is common for them to realize only then how poor they had been feeling for years beforehand.

Sleepiness occurs because the brain wakes up when significant drops in airflow occur. As a result, the brain does not have long, uninterrupted periods of sleep. Sleep is said to be "fragmented." (Imagine if the telephone rang 5 times each hour you slept.)

Most patients with sleep apnea fall asleep quickly. Some, however, may complain of insomnia.

As we will mention below, sleepiness can cause its own complications, for example automobile crashes and other traumatic injuries.

Sleep apnea can affect the brain in other ways. Some persons will not feel as mentally sharp as their normal. Some persons will have a change in personality. There have been reports of depression associated with sleep apnea.

Family members, friends, and co-workers may observe some of the consequences of sleep apnea.

Snoring is a common sign of obstructive sleep apnea.

It is often possible to hear other abnormalities in the breathing sounds made by a person with sleep apnea. A pause in breathing sounds may be heard. Patients with obstructive sleep apnea may make choking-like noises. They may also make sounds with an almost explosive character, as their airway suddenly re-opens after being completely obstructed. Persons who grind their teeth during sleep are more likely to have sleep apnea, but it is unknown if this is a consequence or fellow-traveler of sleep apnea.

Some persons with advanced sleep apnea may develop a ruddy complexion.

On some occasions, a physician or dentist may observe the cause of a patient's sleep apnea, including enlarged tonsils or an enlarged tongue or a "disproportionate" jaw size. A disproportionate jaw is one that is too small for the size of the tongue.

In some cases, rigorous data are lacking, but experts have at least the impression that obstructive sleep apnea (OSA) occurs more commonly in persons with the following:

• Cardiovascular consequences of OSA:
  • hypertension (high blood pressure)
  • heart failure
  • atherosclerosis (heart attacks, angina)
  • atherosclerosis (stroke)
  • atrial fibrillation
  • ventricular arrhythmias
  • pulmonary hypertension
   
• Other consequences of OSA:
  • trauma (traffic accidents)
  • glaucoma
  • snoring spouse syndrome
  • diminished libido
  • in children: illness like attention deficit hyperactivity disorder (ADHD)
  • in children: slowed growth
   
• Other associations with OSA:
  • obesity
  • obesity syndromes, such as Prader-Willi syndrome
  • polycystic ovary disease
  • renal failure
  • hypothyroidism
  • Marfan syndrome
  • Charcot-Marie-Tooth disease
  • post-polio syndrome
  • gastro-esophageal reflux
  • worsening of epilepsy

Hypertension and heart failure are strongly linked with sleep apnea. OSA appears to be a cause of hypertension. It appears that sleep can be either a cause or an effect of heart failure. Recent trials have demonstrated that treating sleep apnea in patients with heart failure is beneficial.

Persons with sleep apnea have an elevated risk of motor vehicle collisions. The risk returns to normal when the sleep apnea is successfully treated.