Hyperarousal dynamics reveal an overnight increase boosted by insomnia.

Area of Science:

• Psychology
• Neuroscience
• Sleep Medicine

Background:

• Hyperarousal is a core symptom in anxiety, stress-related disorders, and insomnia.
• Previous research conceptualized hyperarousal inconsistently, leading to mixed evidence.
• The daily variability of hyperarousal and its link to sleep quality in insomnia remain understudied.

Purpose of the Study:

• To investigate the daily dynamics of state hyperarousal in individuals with insomnia.
• To explore the relationship between day-to-day variations in hyperarousal and subjective sleep quality.

Main Methods:

• Employed ecological momentary assessment over 9 days in 169 individuals with insomnia and 38 controls.
• Utilized exploratory factor analysis to identify a hyperarousal factor (tension, distress).
• Applied adaptive LASSO regression to analyze the association between sleep quality and hyperarousal fluctuations.

Main Results:

• A distinct hyperarousal factor was identified, with higher scores in the insomnia group.
• Hyperarousal peaked in the morning and decreased throughout the day in both groups.
• Individuals with insomnia exhibited a stronger overnight increase in hyperarousal, particularly after nights of poorer sleep quality.

Conclusions:

• Subjective sleep quality is significantly associated with overnight modulations of hyperarousal.
• The findings highlight the interplay between sleep and hyperarousal dynamics in insomnia.
• Interventions targeting sleep quality may be beneficial for disorders characterized by hyperarousal.