There’s plenty of evidence that sleep apnea can increase the risk of stroke. However, a stroke can cause sleep disorders – including apnea.
Strokes almost always result in sleep problems in the weeks and months after the stroke event. These sleep problems can be persistent in older people – the demographic most vulnerable to strokes. Sleep problems after a stroke can become chronic or life-long sleep disorders if left untreated.
Stroke damage can cause Central Sleep Apnea
Strokes can cause a host of problems and disabilities (both acute and chronic). It depends on what part of the brain is damaged. It also depends on the extent of that damage. Specifically, injury to the brain stem from a stroke can cause the most serious sleep disorder: apnea that originates in the brain: ‘central apnea’. This finding is based on a number of studies – including a 2014 study in the US that proved a correlation between brain stem injury from ischemic stroke and post-stroke apnea in 355 individuals over the age of 65 who had recently had a stroke.
Common stroke caused sleep disorders
Many stroke victims experience sleep problems immediately after a stroke. Many continue to suffer from a range of symptoms that interrupt normal, healthy sleep cycles and sleep quality for months, or even years, after a stroke. Again, it all comes down what part of the brain has been damaged, to what extant, and the age and health of the stroke victim.
Acute sleep disorders that can be caused by stroke include:
- Excessive sleepiness – with relentless daytime sleepiness despite sleeping well at night.
- Insomnia – mild to severe, with some sufferers finding it difficult to fall asleep, and others to stay asleep for more than a couple of hours at a time or per night.
Causal links between apnea sleep disorders and stroke
Apnea can cause stroke and stroke can cause apnea. Stroke victims who already have obstructive sleep apnea (OSA) can then go on to develop central sleep apnea (CSA) caused by the stroke. This can increase the risk for further strokes.
OSA and CSA together is termed ‘Complex Sleep Apnea Syndrome. The risk of stroke (and other sleep disorders) is highest in these patients. The risk level can be life threatening in people with CSAS, if the sleep disorder is left untreated.