Sleep Apnea and Sleep-Related Movement Disorders

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Sleep Apnea and Sleep-Related Movement Disorders

By Admin

Many sleep disorders have been linked to sleep apnea, either as symptoms of apnea events or as comorbid relationships, and while the precise nature of these relationships are unknown in most cases, increased research in these areas continues to give us more information on the complex mechanisms involved. Sleep-related movement disorders, for example, have been known to develop as a result of apnea events over prolonged periods of time. Problems such as restless legs syndrome are extremely common among individuals with sleep apnea syndromes, making sleep more difficult and causing further harm to the patient. In these cases, treatments such as continuous positive airway pressure (CPAP) therapy can have a combined effect, not only treating the sleep apnea but also the sleep-related movement symptoms. By screening for these common sleep disorders, doctors and sleep specialists can better assess a patient’s condition and develop a more effective treatment plan that helps both the patient and any bed partner who must cope with the periodic sleep disturbances on a regular basis.

Types of Sleep-Related Movement Disorders

The most common sleep-related movement disorders listed in the International Classification of Sleep Disorders - Third Edition (ICSD-3) include restless legs syndrome (RLS), periodic limb movement disorder (PLMD), rhythmic movement disorder (RMD), bruxism (teeth grinding), and sleep-related leg cramps. All of these disorders involve muscle contractions that occur during sleep. While there is some overlap between these disorders, each represents a persistent and repetitive problem with one form of movement or another.

Restless Legs Syndrome (RLS)

Restless legs syndrome is a common disorder involving discomfort in the legs and intense urges to move or kick during sleep. Unlike some other sleep-related movement disorders, restless legs syndrome involves conscious, voluntary movements, but the impulse to move can be quite extreme. The patient is often awakened from sleep by the discomfort and the urge to move, rather than the movement itself. This disorder is known to cause considerable morbidity and often overlap with other disorders. Research has shown that patients with restless legs syndrome not only have high rates of obstructive sleep apnea, but also diabetes, asthma, and insomnia.

Periodic Limb Movement Disorder (PLMD)

Unlike restless legs syndrome, periodic limb movement disorder involves involuntary movements that occur periodically during sleep. During periodic limb movements, the patient is usually unaware of the behavior, making the movements dangerous to anyone close to them. For this reason, management of the condition can be difficult, and patients often experience mood disturbances and a diminished quality of life. Periodic limb movements occur in roughly 30 percent of those aged 65 or older, and can often be idiopathic, developing on their own or a response to sleep changes or other factors. But in more serious cases, the persistence of these movements, especially during PAP-therapy, can be an indicator of insufficient treatment, increased resistance, or other problems. PLMD has also been linked to stroke and cardiovascular events in patients with sleep apnea.

Bruxism (teeth grinding)

Sleep bruxism is the grinding or clenching of teeth during sleep. This behavior is extremely common, both in the general public and among patients with sleep apnea. Reports of prevalence range from around 8 to 31 percent in the general population, and from 40 to 54 percent among those with sleep apnea. In fact, studies have found a statistically significant association between apnea-hypopnea index (AHI) severity and the extent of tooth wear in patients with obstructive sleep apnea. Fortunately, the use of CPAP therapy is highly effective in eliminating the episodes altogether. For those without sleep apnea, oral appliances such as mouth guards can be used to keep the teeth apart during sleep. Without treatment, significant damage can be done to teeth, gums, and other areas of the mouth and jaw. While the symptoms of bruxism can be difficult to detect in the beginning, they can cause significant harm in the long term and can be costly as well, resulting in dental and/or orthodontic work to repair the damage.

Rhythmic Movement Disorder (RMD)

Rhythmic movement disorder (RMD) is a neurological disorder that involves involuntary rhythmic movements during sleep or sleep onset. Often involving the head and neck, these movements are often associated with other disorders, diseases, or psychiatric conditions. As with periodic limb movement disorder, rhythmic movement disorder can cause potential harm to the patient if left untreated. Sometimes called sleep-related rhythmic movements (SRRMs), these disturbances are often linked to sleep-disordered breathing such as sleep apnea. In these cases, treatment with CPAP is recommended to reduce the apnea-hypopnea events that can contribute to rhythmic movement problems.

Sleep-Related Leg Cramps

Sleep-Related Leg Cramps (also known as “nocturnal leg cramps”) are cramps in the leg muscles during sleep, before sleep, or during waking. These contractions can be painful and usually occur in the calf or the lower leg or foot. Some patients also have residual pain after the cramping passes, and the frequency of events ranges from occasional episodes to persistent problems over time. Sleep-related leg cramps are often idiopathic, but can also be linked to other sleep disorders. Like other sleep-related movement disorders, nocturnal leg cramps have shown reductions from consistent use of CPAP, but for patients without a sleep apnea diagnosis, use of massage therapy, heating pads, or cold packing before bed can help reduce the symptoms.

Sleep Hygiene and Sleep Disorder Treatment

Good sleep hygiene, when practiced regularly, can do a lot for any sleep problems. Over time, these habits help to restore proper functioning and vitality, and contribute to more effective memory and immune system functions. Avoidance of any aggravating factors, regular exercise, reduced caffeine intake, and regular scheduled sleep times can help synchronize your daily habits with the body’s natural circadian rhythms. But in addition to these efforts, accurate diagnosis and examination by a medical professional are essential to sleep health and overall wellbeing. When sleep disorders persist, a number of effective treatments are available, but other possible disorders or underlying conditions should be considered in determining the best treatment option available. Some pharmacotherapeutic approaches have been effective in reducing sleep-movement symptoms, for example, dopaminergic medications, gabapentin, benzodiazepines, or in some cases, opioids. But these medications can affect other conditions, and must be balanced holistically to maximize the positive effects of the drug and minimize any possible side effects or interactions. This is why lifestyle changes and improved sleep hygiene are good starting points for any sleep-related disturbances. Even when patients are already using CPAP, which is effective in reducing sleep-related movements as well as sleep apnea, it is important to keep track of any additional sleep disorder symptoms, as they can be signs of other problems in need of attention. Whether occasional or persistent, these types of night movements should be addressed proactively to ensure the health and safety of patients as well as any partners or loved ones who share their space.