Test-Retest Reliability of Two Consecutive Mean Sleep Latency Tests in Patients with Hypersomnia

Area of Science:

• Neurology
• Sleep Medicine
• Clinical Neurophysiology

Background:

• The reliability of consecutive daily Mean Sleep Latency Testing (MSLT) in diagnosing hypersomnia, particularly hypersomnia without cataplexy, remains under-investigated.
• Accurate diagnosis of hypersomnolence disorders is crucial for effective patient management and treatment.

Purpose of the Study:

• To evaluate the reliability and consistency of MSLT results over two consecutive days in patients diagnosed with hypersomnia without cataplexy.
• To determine if a single day of MSLT is sufficient for diagnosing pathological hypersomnia under specific protocol conditions.

Main Methods:

• A retrospective review of 29 patients with hypersomnia without cataplexy who completed a two-day consecutive MSLT protocol.
• Analysis of Mean Sleep Latency (MSL) values and agreement for pathological hypersomnia (MSL ≤ 8 minutes) between the two testing days.
• Subgroup analysis was performed for patients without sleep apnea.

Main Results:

• The average MSL was consistent across both days (10.9 minutes on Day 1 and 10.9 minutes on Day 2).
• High agreement was observed for diagnosing pathological hypersomnia between the two MSLT days (k=0.85 overall, k=0.76 in patients without sleep apnea).

Conclusions:

• A single MSLT day is sufficient for diagnosing hypersomnia in patients with subjective complaints when a meticulously controlled protocol is employed.
• The findings suggest that adding a second day of MSLT may not be necessary for patients meeting specific diagnostic criteria and protocol adherence, potentially streamlining the diagnostic process.