Which sleep-related disorder is characterized by an urge to move the legs that is relieved by movement and worsens at night?

Which sleep-related disorder is characterized by an urge to move the legs that is relieved by movement and worsens at night?

• A. Narcolepsy
• B. Restless legs syndrome
• C. REM sleep behavior disorder
• D. Insomnia

Answer: (B)

Restless legs syndrome is defined by an urge to move the legs accompanied by uncomfortable sensations that begin or worsen during periods of rest, are relieved by movement, and most often worsen in the evening or at night. This pattern explains why sleep is disrupted: the need to move to relieve symptoms tends to occur when one is trying to sleep or stay asleep, leading to difficulty with sleep onset or continuity. In contrast, narcolepsy centers on daytime sleepiness and features such as sudden muscle weakness (cataplexy) or sleep attacks, not a leg‑related urge. REM sleep behavior disorder involves acting out dreams during REM sleep due to loss of normal atonia, not a persistent urge to move the legs at rest. Insomnia refers to difficulty falling or staying asleep without the characteristic leg sensations and urge to move present in restless legs syndrome.

Restless legs syndrome is defined by an urge to move the legs accompanied by uncomfortable sensations that begin or worsen during periods of rest, are relieved by movement, and most often worsen in the evening or at night. This pattern explains why sleep is disrupted: the need to move to relieve symptoms tends to occur when one is trying to sleep or stay asleep, leading to difficulty with sleep onset or continuity.

In contrast, narcolepsy centers on daytime sleepiness and features such as sudden muscle weakness (cataplexy) or sleep attacks, not a leg‑related urge. REM sleep behavior disorder involves acting out dreams during REM sleep due to loss of normal atonia, not a persistent urge to move the legs at rest. Insomnia refers to difficulty falling or staying asleep without the characteristic leg sensations and urge to move present in restless legs syndrome.