Heart rate variability across recording conditions: Associations with depression and burnout in inpatients with...

Heart rate variability (HRV) is a non-invasive marker of the autonomic nervous system and may be a promising mental health indicator. However, the existing literature lacks clarity regarding which HRV parameter and recording condition feasibly reflects the severity of depression and burnout. This study aimed to evaluate HRV across recording conditions in relation to depression and burnout severity in inpatients with stress-related disorders.

Inpatients (n = 153) diagnosed with burnout syndrome and either depressive episode or adjustment disorder (aged 27-64 years, 88 female) were included. At baseline and after up to 8 weeks of treatment, HRV was assessed during "supine", "standing", "post-exercise", and over 24 h, while symptom severity was rated with the Shirom-Melamed-Burnout-Measure (SMBM) and the Beck Depression Inventory-II (BDI-II).

Non-linear associations emerged between SMBM score and normalized high and low frequency (HF & LF) HRV during "standing". Results provided little evidence for associations between BDI-II score and any assessed HRV parameter at baseline. After treatment, mean heart rate and 5-min heart rate recovery during "post-exercise" decreased, while root mean square of successive differences, standard deviation of NN interval (SDNN), HF, and LF during "supine" and 24-h SDNN increased.

Our results suggest that HRV may not be a reliable indicator of depression severity at the beginning of treatment. The post-exercise and supine recordings appear to be best suited for detecting changes in HRV over a short period of time.

NCT05874856 on May 22, 2023.