A number of medical conditions may be associated with disorders of sleep. In some cases, severe obesity alone may also lead to breathing abnormalities in sleep.
Patients who develop sleep-related breathing problems may commonly experience morning headaches, daytime sleepiness or difficulty concentrating during the day. It is vital to recognise these problems when they exist, as they may lead to worsening of the underlying condition. For conditions associated with breathing abnormalities in sleep treatment similar to that for obstructive sleep apnoea (OSA) is often effective.
A few examples of other conditions associated with sleeping disorders are:
- Hypertension (high blood pressure)
- Heart failure
- Parkinson's disease
- Chronic pain syndromes treated with opiate medications
- Muscular dystrophies including Motor Neurone Disease
Obesity hypoventilation syndrome
Some cases of severe obesity may lead to persistent underbreathing or 'hypoventilation' during sleep. People who develop obesity hypoventilation syndrome commonly experience night-time or morning headache, daytime sleepiness or difficulty concentrating during the day. They may develop progressive respiratory failure in the daytime as well.
Hypertension / High blood pressure
This disorder is frequently associated with obstructive sleep apnoea, particularly in people with difficult to control blood pressure (i.e. needing three or more blood pressure medications). In short term studies, treatment of obstructive sleep apnoea has been shown to improve blood pressure control. If someone with high blood pressure has symptoms to suggest sleep apnoea it is important to check for this condition.
Heart failure is strongly associated with both obstructive sleep apnoea and a condition called central sleep apnoea or Cheyne Stokes Respiration. In central sleep apnoea, subjects recurrently stop breathing. This is the result of abnormal control of breathing, not airway obstruction. More than 40% of people with heart failure have either obstructive sleep apnoea or central sleep apnoea or both. Treatment of obstructive sleep apnoea has been shown to improve the function of the heart in short term studies. While treatment of central sleep apnoea may improve symptoms of sleep disruption, it has not yet been shown to improve heart function.
Parkinson's disease is often associated with excessive daytime sleepiness. This may be due to the sleep disruption caused by stiffness and abnormal movements or the disease process itself. Some of the medications used to treat Parkinson's disease have been associated with—what have been described as—sleep attacks.
Chronic pain syndromes treated with opiate medications
Having a chronic pain disorder, not surprisingly, may interfere with sleep quality. It is becoming apparent, however, that being on high doses of opiate pain medications may predispose to abnormal breathing at night—which is a form of central sleep apnoea syndrome. This may contribute to additional sleep disruption and can be difficult to treat medically. Reducing the dose of opiates to the minimum required to maintain pain control may help.
Muscular dystrophies including Motor Neurone Disease
The muscle weakness caused by chronic pain disorders may cause significant underbreathing at night. This causes the waste gas carbon dioxide to build up at night and a low oxygen level during sleep. Symptoms of sleep-related breathing abnormality in neuromuscular conditions like motor neurone disease may include shortness of breath while lying flat, gasping at night and morning headaches. These symptoms can be eased considerably by a machine to assist breathing at night.