Korean J Psychosom Med.  2020 Jun;28(1):89-97. 10.22722/KJPM.2020.28.1.89.

Reduced Heart Rate Variability in Somatic Symptom Disorder: Associations with Alexithymia

• Lee JH
• Jang YE
• Park HY

• KMID: 2503774
• DOI: http://doi.org/10.22722/KJPM.2020.28.1.89

Abstract

Objectives
：We investigated heart rate variability (HRV) patterns in patients with somatic symptom disorder (SSD) and the relationships of these patterns with alexithymia.
Methods
：In total, 42 patients with SSD and 33 healthy controls were enrolled in this study. Demographic, psychological, and HRV data were assessed at baseline, and 24 patients with SSD were reassessed after 6 months of treatment. The psychological data included somatic symptoms and levels of depression, anxiety, and alexithymia as indicated by the somatic symptom subscale of the Symptom Checklist 90-Revision (SCL-12), Beck Depression Inventory-II (BDI-II), Beck Anxiety Inventory (BAI), and the Toronto Alexithymia Scale 20 (TAS-20), respectively.
Results
：Patients with SSD had a lower standard deviation of normal-to-normal R-R intervals (SDNN) and lower proportions of adjacent R-R intervals greater than 50 milliseconds (pNN50) compared with controls. These HRV parameters were negatively correlated with alexithymia severity. After treatment, patients exhibited significantly decreased levels of somatic symptoms and reduced anxiety and depression, but there were no significant differences in the HRV parameters. In patients with alexithymia, a high baseline SDNN and pNN50 were associated with a decrease in somatic symptoms.
Conclusions
：Patients with SSD have different HRV patterns, and several HRV parameters are associated with alexithymia severity. These findings suggest that ANS regulation is involved in the pathophysiology of SSD, mediated by alexithymia. Furthermore, these results suggest that certain HRV parameters may be associated with clinical outcomes of SSD.

Keyword

Autonomic nervous system; Heart rate variability; Somatic symptom disorder