Periodic Limb Movement Disorder

Reflections on PLMD as a Cause of Sleep Disruption

Periodic Limb Movement Disorder (PLMD) is a sleep-related movement disorder characterized by involuntary acts of the legs or arms during sleep in a periodic and repetitive manner. These limb movements can cause frequent arousals, thus disrupting the sleep quality of patients, leading to excessive daytime sleepiness and even fatigue. PLMD is also sometimes called nocturnal myoclonus. While PLMD can affect anyone, it occurs most often in middle-aged and older adults.

Signs and Symptoms of PLMD

In most instances, patients suffering from PLMD are likely to have:

Uncontrollable repetitive jerks/twitches of the legs (sometimes of the arms too) during sleep.
Frequent waking and sleepy disruptions with little awareness.
Excessive daytime sleepiness, fatigue, and concentration problems.
Legs generally restless, possibly in analogy with RLS.

Many persons with PLMD do not know they are performing those movements; it is only when the bed partner remarks on their acts or they have soundly grown aware from persistent daytime fatigue that they recognize the signs and symptoms.

Causes and Risk Factors

There are instances where the actual cause of PLMD sets in without clear reasons. Some of the proposed adjunctive causes have included:

Brain impairment – In essence, the PLMD is thought to be abnormal signaling from the brain controlling muscle movement most often during sleep.
Number-two; iron deficiency – When iron levels in the body are low, its production of dopamine, the neurotransmitter that regulates movement, may be affected.
Causation by drugs – A class of drugs including some antidepressants, certain antipsychotics, and some antihistamines can instigate and exacerbate PLMD symptoms.
Other medical conditions – PLMD may be influenced by conditions such as Restless Legs Syndrome (RLS), diabetes, multiple sclerosis, or spinal cord injury.

How is PLMD Diagnosed?

If PLMD is suspected, polysomnography (sleep study) is indicated to monitor limb movements in sleep, brain activity, and sleep patterns and is usually ordered by the sleep specialist. A comprehensive medical history and blood work may be performed to help rule out other possible causes such as iron deficiency or conditions affecting the nervous system.

Treatment Options for PLMD

PLMD does not need treatment except when it brings about daytime dysfunction; thus, the severity of sleep disturbance acts as an indicator for treatment. Some options available include:

Lifestyle and Behavioral Changes

Keep the same sleep hours each day.
Avoid caffeinated beverages or products, nicotine, and alcohol in the evening and before sleep.
Practice relaxation activities like mediation or gentle stretching for about one hour before trying to sleep.
Exercise regularly but not within two hours of bedtime.

Medical Treatment

Iron supplements: if low iron levels are detected.
Dopaminergic medication to control neurotransmitter involved in movement.
Benzodiazepines or muscle relaxants to help with excessive movement of limbs.

PLMD versus Restless Legs Syndrome (RLS): What Is Different?

Although PLMD and RLS are frequently inextricably linked, the two conditions remain distinct from one another.
PLMD occurs only in sleep and is attributed to involuntary action.
RLS gives rise to an irresistible urge to move the legs while awake, especially during relaxation, and moving relieves the urge.

Some individuals may experience both conditions, hence proper diagnosis is important.

Consultation for PLMD

If either you or a loved one are experiencing anxiety due to sleep disturbances, daytime sleepiness, or other nocturnal limb movements, feel free to approach Sleepologie Health and Wellness. Your sleep specialists will provide thorough assessment, recommendation, and a treatment plan specifically geared towards achieving your sleep restoration goals.