RPSGT RPSGT Sleep Disorders & Pathophysiology 5

Question 1

Which criterion best distinguishes idiopathic hypersomnia from narcolepsy type 1 on MSLT?

Accepted Answer

Mean sleep latency under 8 minutes with fewer than 2 SOREMPs

Answer

Idiopathic hypersomnia shows a mean sleep latency ≤8 minutes on MSLT with fewer than 2 sleep-onset REM periods, distinguishing it from narcolepsy which requires ≥2 SOREMPs.

Question 2

Restless legs syndrome (RLS) is most closely associated with dysfunction in which physiological system?

Accepted Answer

Iron-dopamine metabolism in the basal ganglia and spinal cord

Answer

RLS pathophysiology involves impaired iron metabolism reducing dopaminergic function in the basal ganglia and spinal cord, explaining the response to dopaminergic medications.

Question 3

A 35-year-old shift worker complains of inability to sleep at the right times and excessive sleepiness at work. Actigraphy over 14 days shows normal total sleep time but misaligned timing. What is the most likely diagnosis?

Accepted Answer

Shift work sleep disorder

Answer

Shift work sleep disorder is characterized by insomnia and/or excessive sleepiness caused by a work schedule that overlaps with the usual sleep period.

Question 4

Which of the following is the minimum SpO2 threshold and duration used by AASM to score sleep-related hypoxemia in adults?

Accepted Answer

SpO2 below 88% for at least 5 minutes cumulative during sleep

Answer

Per AASM criteria, sleep-related hypoxemia in adults is scored when SpO2 is below 88% for ≥5 cumulative minutes during sleep.

Question 5

In the pathophysiology of obstructive sleep apnea, which anatomical factor is the PRIMARY determinant of pharyngeal collapsibility?

Accepted Answer

Negative intraluminal pressure during inspiration relative to upper airway muscle tone

Answer

OSA occurs when inspiratory negative intraluminal pressure exceeds the capacity of pharyngeal dilator muscles (especially genioglossus) to maintain airway patency.

RPSGT Exam Practice Test

RPSGT Exam Practice Test

RPSGT RPSGT Sleep Disorders & Pathophysiology 5