Can continuous heart rate variability monitoring, combined with contextual and psychological measures be used to detect patterns of stress and recovery in medical doctors?

Background
Burnout is a rising concern among medical doctors. Heart rate variability (HRV), a non-invasive measure of autonomic nervous system activity, reflects physiological states of sympathetic (stress) and parasympathetic (recovery) activity. While HRV is known to provide insight into momentary stress responses, its utility over extended time periods remains unclear.

Aims
Understand the utility of HRV as an objective measure of stress and recovery.


Methods
A systematic review was conducted (PROSPERO: CRD42023413282) with a comprehensive search of databases and grey literature sources coupled with hand citation searching. Primary studies were eligible where they reported at least one recognised HRV parameter combined with at least one contextual or psychological assessment and assessed over a period lasting 24 hours or more.
Two independent reviewers assessed abstracts and full texts against inclusion criteria, with a third reviewer resolving disagreements. Extracted data included study population, methodological factors including HRV device, HRV parameters reported, length of HRV measurement and contextual and psychological measures used. Methodological quality was assessed using the JBI risk of bias assessment for case reports (JBI, 2020) and STARD(HRV) (Dobbs et al, 2019).

Results
After removing duplicates, 677 abstracts were screened, resulting in 39 full-text reviews. Thirteen studies met the inclusion criteria, with three subsequently excluded due to HRV reporting methods and one due to the overall poor quality of the review. Substantial heterogeneity existed, and while all studies reported an association between HRV and stress and recovery, methodological diversity was considerable. HRV measurement periods ranged from 24-48 hours, a wide variety of devices were used, the most frequently used psychological measures were the State-Trait Anxiety Inventory (n=2) (Spielberger et al,1983) and the Job Content Questionnaire (n=2) (Karasek, 1985).

Conclusions
Continuous heart rate variability monitoring combined with contextual measures proves useful in tracking stress and recovery patterns. However, further high-quality studies are required, particularly to understand the association between HRV and subjective measures of stress.