Question:

I have noticed that my husband trembles and experiences tremors while he is sleeping. He is not aware of them. He says he is fast sleep. Also he is a very deep sleeper. These tremors don`t disturb him but I just want to make sure that they don`t point to some disorder.

Answer:

The answer to this question really depends upon further history about the nature of the “tremors” you mention. Potential causes of such symptoms range from normal physiology in sleep to significant but treatable sleep disorders. Normal causes of shakes, jerks or tremors may include sleep starts, or sudden jerks as one is falling asleep, and periodic limb movements, most commonly seen in the first third of the night.

Sleep disorders that may cause “tremors” ranges from disorders that fragment or briefly arouse the patient from sleep, such as sleep apnea or periodic limb movement disorder, to parasomnias, such as REM behavior disorder, to a wide range of uncommon sleep-related movement disorders. In this answer, I will address the potential sleep disorders that may be contributing to your husband’s symptoms.

Obstructive sleep apnea (OSA) affects up to 5% of middle aged adults in America. It is due to the recurrent complete or partial closure of the airway during sleep. When one of these breathing disturbances occurs during sleep, a brief arousal usually results in order to establish normal breathing again. During this arousal, it is very common for patients to jerk or shake their body or limbs, depending on the severity of the sleep apnea. As a result, individuals with OSA suffer from fragmented sleep and tend to feel unrefreshed upon awakening as well as sleepy and tired during the daytime.

The main risk factors for the development of sleep apnea include being overweight and having specific anatomic abnormalities (such as large tonsils) that may narrow the airway. Aside from unrefreshing sleep and daytime sleepiness, individuals with sleep apnea often complain of loud snoring, headaches upon awakening, a poor sense of well-being, decreased ability to concentrate and reduced alertness. Increasing research also suggests that OSA may impact other medical conditions, including blood pressure control and risk for cardiovascular disease (such as heart attacks, heart failure and stroke). Thus, it is important to diagnose and treat this condition. The diagnosis typically requires a sleep study.

Periodic limb movement disorder is another sleep condition that can lead to brief awakening associated with jerks, primarily in the legs. The main symptom seen with this is frequent leg jerks during sleep that disrupt sleep, resulting in unrefreshing sleep and daytime sleepiness. Often times, an individual’s bed partner is the first to complain about this problem. This condition also requires a sleep study to make the diagnosis and treatment is generally managed with medical therapy. Of note, these leg jerks may be part of normal sleep in some patients, particularly if they occur in the first third of the night and the patient is not aware of them nor do they complains of the associated symptoms.

Of the parasomnias that may result in abnormal movements in sleep, REM behavior disorder is the most likely to initially present as jerks or tremors, usually associated with dreams. Patients will often recall the dream and are usually attempting to act out a part of the dream when the movements occur. Usually, these movements are purposeful, such as running or hitting, and are often associated with bad or violent dreams. To diagnose this condition, a detailed history and sleep study are required.

There are a number of unusual movement disorders that can be associated with sleep (i.e. Alternating Leg Muscle Activation, Excessive Fragmentary Myoclonus, etc.). These often have specific features in the history that will help with making the diagnosis. A seizure disorder should also be considered, though this would be unusual to happen regularly only during sleep.

To determine if there is sleep disorder present as the cause for your husband’s problems, a thorough history and physical examination are needed. A referral to a Sleep Specialist by your husband’s Primary Care Physician should be considered to help sort out whether further testing is needed. Once a history and physical examination have been performed, the Sleep Specialist will decide if further evaluation is necessary. If a primary sleep disorder is discovered, you should maintain hope as most of these are treatable.

To learn more about sleep and sleep disorders, please visit the American Academy of Sleep Medicine website. In addition to information, the website contains a list of Sleep Centers across the country so that you may locate one near you.

Good luck and here’s to better sleep!

For more information:

Go to the Sleep Disorders health topic.