Sleep-based heart period variability in panic disorder with and without nocturnal panic attacks

Area of Science:

• Psychiatry
• Cardiology
• Sleep Medicine

Background:

• Panic disorder is characterized by recurrent panic attacks.
• Nocturnal panic attacks (NP) occur during sleep, distinct from daytime panic.
• Autonomic nervous system dysfunction is implicated in panic disorder.

Purpose of the Study:

• To investigate heart period variability (HPV) during sleep in individuals with nocturnal panic (NP) compared to those with only daytime panic attacks and non-anxious controls.
• To explore the relationship between fear of relaxation/sleep and autonomic function in panic disorder subtypes.

Main Methods:

• Ambulatory sleep monitoring to assess heart period variability (HPV).
• Comparison of HPV measures between NP participants, daytime panic participants, and non-anxious controls.
• Self-report questionnaires assessing fear of relaxation and sleep.

Main Results:

• Significantly reduced time-derived HPV during sleep was observed in the NP group (n=32) compared to daytime panic (n=17) and control (n=17) groups.
• NP participants reported greater fear of relaxation and sleep than the other groups.
• Findings align with neurovisceral models predicting reduced HPV in dysregulated behavioral adaptation.

Conclusions:

• Reduced sleep-time heart period variability is associated with nocturnal panic disorder.
• Autonomic dysregulation during sleep may be a key feature of NP.
• Further research into neurovisceral integration in NP is warranted.