ABPN Sleep Medicine and Neurological Disorders Flashcards

Which condition is characterized by bilateral leg discomfort that worsens at rest and in the evening, is relieved by movement, and interferes with sleep?

Answer: Restless legs syndrome (RLS)

Restless legs syndrome has four diagnostic criteria: urge to move legs, worsening at rest/evening, temporary relief with movement, and not solely explained by another condition.

Fatal familial insomnia is caused by a mutation in which gene?

Answer: PRNP (prion protein gene)

Fatal familial insomnia is caused by a D178N mutation in the PRNP gene, leading to prion accumulation in the thalamus and destruction of sleep-regulatory circuits.

A multiple sleep latency test (MSLT) showing a mean sleep onset latency of 4 minutes and two or more sleep-onset REM periods (SOREMPs) is MOST consistent with which diagnosis?

Answer: Narcolepsy

Narcolepsy is diagnosed by MSLT showing mean sleep latency ≤ 8 minutes and ≥ 2 SOREMPs, reflecting intrusion of REM sleep into wakefulness.

Which neurological condition is characterized by brief, involuntary jerks of the legs during sleep and is associated with periodic leg movements on polysomnography?

Answer: Periodic limb movement disorder (PLMD)

PLMD is characterized by repetitive, stereotyped limb movements (typically legs) during sleep on polysomnography, causing sleep disruption and daytime fatigue.

Continuous positive airway pressure (CPAP) is the FIRST-LINE treatment for moderate-to-severe obstructive sleep apnea. What is the primary mechanism by which CPAP prevents apneas?

Answer: It provides pneumatic splinting to maintain upper airway patency

CPAP delivers continuous pressurized air that acts as a pneumatic splint, preventing collapse of the pharyngeal soft tissues that cause obstruction.

Which condition presents with episodic hypersomnia (sleeping 16-18 hours per day), hyperphagia, hypersexuality, and behavioral changes lasting days to weeks followed by complete return to normal?

Answer: Kleine-Levin syndrome

Kleine-Levin syndrome is a rare condition predominantly affecting adolescent males, characterized by recurrent hypersomnia episodes with cognitive, behavioral, and sometimes hypersexual features.