skip to main content

Narcolepsy Type 2 — SCE Neurology MCQ

Instant feedback + full explanation. One question, done properly.

HardSleep DisordersNarcolepsy Type 2SCE Neurology

A 50-year-old man has daily unrefreshing sleepiness, sleep inertia and long unbroken nocturnal sleep. Actigraphy confirms adequate sleep opportunity. Polysomnography excludes obstructive sleep apnoea and shows no sleep-onset REM period; MSLT mean sleep latency is six minutes with one sleep-onset REM period. He has never had cataplexy. Which diagnosis is most likely?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: C — Idiopathic hypersomnia

Idiopathic hypersomnia is supported by objective pathological sleepiness with fewer than two sleep-onset REM periods after exclusion of insufficient sleep and other sleep disorders. Narcolepsy type 2 requires at least two SOREMPs across overnight polysomnography and MSLT, while type 1 also requires cataplexy or documented hypocretin deficiency. Sleep inertia and prolonged unrefreshing sleep further support idiopathic hypersomnia.

Reference: European narcolepsy guideline: https://pubmed.ncbi.nlm.nih.gov/27359185/