Periodic Limb Movements
Periodic Limb Movements (PLMS/PLMD)
Periodic limb movements of sleep (PLMS) are repetitive twitching or kicking movements, usually of the legs, that happen every 20 to 40 seconds during sleep. Most people are not aware of them, but a bed partner may notice. PLMS become more common with age.
When these movements disrupt sleep and cause symptoms that are not explained by another condition, it is called periodic limb movement disorder (PLMD). Possible signs include:
- Unrefreshing sleep or frequent awakenings
- Daytime fatigue or sleepiness
- A bed partner reporting kicking or jerking legs
- Disturbed sleep for your bed partner
Most people with restless legs syndrome also have PLMS. Periodic limb movements are also linked to low iron, sleep apnea and some antidepressant medications.
Diagnosis & Treatment
How we diagnose PLMS and PLMD
Periodic limb movements are measured with an overnight in-lab sleep study (polysomnogram), which records leg muscle activity along with breathing, brain waves and oxygen levels. This also lets us check for sleep apnea, which can cause similar movements. We may also check ferritin and iron levels.
Treatment options
- Treating low iron stores
- Reviewing and adjusting medications that can increase limb movements
- Treating coexisting sleep apnea or restless legs syndrome
- Medication when movements clearly disrupt sleep
See also: Restless Legs Syndrome · Sleep Studies