A pattern-based heart rate variability approach in somatic symptom disorder: Evidence from the SOMA.SSD study

Area of Science:

• Psychosomatic Medicine
• Autonomic Nervous System Research
• Cardiology

Background:

• Heart rate variability (HRV) is explored as a marker for autonomic dysfunction in somatic symptom disorder (SSD).
• Previous studies using single HRV parameters yielded inconsistent findings.
• Pattern-based HRV analysis offers a more integrated approach to characterizing autonomic regulation.

Purpose of the Study:

• To investigate the utility of a four-pattern HRV classification in patients with SSD.
• To examine the association between HRV patterns and psychopathology in SSD.
• To assess the longitudinal stability of these associations.

Main Methods:

• A cohort of 148 SSD patients (SOMA.SSD) was classified into four HRV patterns: normal, low, relatively high sympathetic, and relatively high vagal.
• Resting-state HRV was measured via 5-minute ECG recordings.
• Psychopathology was assessed using PHQ-15, PHQ-9, and SSD-12 at baseline, 6, and 12 months, with statistical analyses including ANOVA and linear mixed-effects models.

Main Results:

• No significant baseline differences in symptom levels were found across the four HRV pattern groups.
• Patients with a low HRV pattern reported significantly higher somatic symptom severity, depressive symptoms, and SSD-related distress compared to the normal HRV group.
• These differences persisted over 12 months, with no significant time or interaction effects observed. Other HRV patterns showed no association with psychopathology.

Conclusions:

• A pattern-based HRV classification is feasible and clinically relevant in SSD patients, particularly identifying the significance of a low HRV pattern.
• This approach may facilitate physiologically informed subtyping in psychosomatic research.
• The findings suggest potential implications for future clinical stratification of SSD patients based on HRV patterns.