Sleep apnea is a sleep disorder in which breathing stops and starts throughout the REM cycle. It is a very common condition in the US and it occurs when the upper airway becomes blocked repeatedly during sleep. If the brain doesn’t send the signals needed to continue breathing, the condition is called central sleep apnea. Sleep Apnea is generally caused by obesity, large tonsils, endocrine disorders, neuromuscular disorders, heart or kidney failure, certain genetic syndromes and premature birth.
Symptoms of sleep apnea include loud and persistent snoring, pauses in breathing during sleep, choking or gasping for air during sleep, restless sleep, and frequent visits to the bathroom. Symptoms present themselves during the day as well and include morning headaches, excessive daytime fatigue, poor concentration, depression, and sleepiness during routine activities. Sleep apnea can also cause essential tremor like symptoms. Essential tremor is not a side-effect of sleep apnea nor sleep apnea a symptom of essential tremor. But, sleep apnea can cause tremors and tremor like symptoms like muscle spasms in the hands, arms, head, and trunk.
There are risks associated with untreated sleep apnea and they can be long term depending on the severity. These include high blood pressure, irregular heartbeat, heart disease, stroke, diabetes and driving and work-related accidents. 800,000 US drivers were involved in sleep apnea related traffic accidents in the year 2000. Those with sleep apnea have 3 times greater risk of stroke among patients with moderate sleep apnea that has not been treated.
It has been found that sleep problems are a common complication of Parkinson disease, and patients with essential tremor. Since essential tremor shares a lot of features of Parkinson disease, and has been shown to have a relationship with the disease, it would make sense that essential tremor sufferers may also have symptoms such as sleep apnea. Research has found though, that those with Parkinson disease are much more likely to have sleep apnea than those that have essential tremor. Because of the difference in the movement disorders, they each present their own sleep-related issues. There have not been many studies researching these two diseases and sleep apnea, so hopefully it will be continually investigated.
Essential tremor may contribute to pathophysiological changes in the brain, which can lead to depressive symptoms and cognitive changes. These may eventually cause sleep abnormalities. After an intensive study, some sleep scores in essential tremor were intermediate between those of Parkinson disease cases and normal cases, meaning that there may be a mild form of sleep interruption and dysregulation could be present in essential tremor. It has also been shown that those with essential tremor react to medication differently, and more medications have a sleep effect to them than others. This can also cause sleep dysregulation. Those with essential tremor can also tolerate less caffeine, which can influence their sleep when caffeine is or is not consumed compared to regular intake. The other neurological effects may have something to do with the sleep disruption, as essential tremor does have depressive side effects in some people.