What is PLM in sleep study?

People with PLMD experience repetitive jerking, cramping, or twitching of their lower limbs during sleep. These are known as periodic limb movements (PLMS) and happen every 5 to 90 seconds for up to an hour.

How do you diagnose PLMS?

Diagnosis. The gold standard for diagnosis of PLMS is a sleep study called a polysomnogram. As part of this study, superficial electrodes are placed on the legs and sometimes even the arms. These are able to detect any muscle contraction or movements.

What is a PLMS arousal?

Purpose. Periodic limb movements in sleep (PLMS) are related to arousal, sympathetic activation, and increases in blood pressure (BP), but whether they are part of the arousal process or causative of it is unclear. Our objective was to assess the temporal distribution of arousal-related measures around PLMS.

What is PLM movement?

Periodic limb movements (PLMs) are characterized by stereotyped, repetitive, non-epileptic movements of the limbs, more frequently in legs. They occur during wakefulness preceding sleep onset (PLMW) and during sleep (PLMS).

How does the PLM index affect the LM?

We investigated to what extent changes in PLM criteria for leg movement duration, intermovement interval and combination of bilateral leg movements (LM) influence the PLM index.

How is PLM index related to other sleep disorders?

PLM index < 5 In OSA & other sleep disorders, increased N1 (light sleep), decreased REM (OSA more severe) Sleep Study Sample Report EEG Data: sleep architecture & arousals This patient has relatively normal sleep stages and efficiency and latency for the sleep lab.

Why does the frequency of PLMS increase with age?

The frequency of PLMS is influenced by the time of night and the patient’s sleep position. Although the prevalence of PLMS increases with age, the periodic limb movement index (number of periodic limb movements per hour of sleep) does not. PLMS occur as one of two patterns.

How is the PLM-arousal index and Nonarousal index calculated?

Arousals were scored for those patients studied within the last 4 yr of data collection and in specific sleep recording rooms; assignment to these rooms was essentially but not formally random. The PLM-arousal index and the PLM-nonarousal index were calculated as the number of events per hour of sleep ( 1 ).