The first night effect in multiple sclerosis patients undergoing home-based polysomnography.

Area of Science:

• Neurology
• Sleep Medicine
• Medical Technology

Background:

• The first night effect (FNE) is a known polysomnography (PSG) habituation phenomenon, typically observed in laboratory settings.
• A reverse FNE (RFNE), indicating improved sleep on the first night, is associated with insomnia.
• Limited data exists on FNE and RFNE in home-based PSG (H-PSG) settings.

Purpose of the Study:

• To investigate the presence and characteristics of FNE and RFNE in multiple sclerosis (MS) patients undergoing H-PSG.
• To determine if H-PSG requires multiple nights for accurate sleep assessment in different MS patient subgroups.

Main Methods:

• Retrospective analysis of a cross-sectional study involving 63 MS patients undergoing two consecutive H-PSGs without video.
• Patients were categorized into subgroups: no sleep disorder, insomnia, sleep-related breathing disorders (SRBDs), and periodic limb movement disorder/restless legs syndrome (PLMD/RLS).
• Analysis focused on differences in sleep parameters between the first and second H-PSG recordings.

Main Results:

• MS patients with insomnia did not exhibit an RFNE.
• MS patients with SRBD or PLMD/RLS showed reduced slow-wave sleep but no decrease in overall sleep efficiency.
• SRBD patients had less NREM sleep, while PLMD/RLS patients exhibited increased wake-after-sleep-onset and longer REM latency.

Conclusions:

• A significant FNE was observed in MS patients with SRBD and PLMD/RLS, necessitating two consecutive H-PSGs for accurate hypnogram generation.
• In MS patients with insomnia, the absence of RFNE suggests that a single H-PSG may be sufficient for diagnosis.
• These findings highlight the importance of considering the specific sleep disorder when determining the number of H-PSGs required for accurate assessment in MS patients.