In case anyone is wondering why I’m linking to all of these studies that are unrelated to acupuncture, it’s because the direction I’m trying to go in my work is a means to make sense of the different HRV responses in individuals.  There are quite varied responses, but they tend to remain consistent within the individual.  Do they have significance to clinical outcomes?  Can they help to tailor treatment?
Biomed Res Int. 2015; 2015: 431725.
Published online 2015 Oct 18. doi:  10.1155/2015/431725
PMCID: PMC4628754
Burnout Is Associated with Reduced Parasympathetic Activity and Reduced HPA Axis Responsiveness, Predominantly in Males
There is mounting evidence that burnout is a risk factor for cardiovascular disease (CVD). Stress-related dysregulation of the sympathetic and parasympathetic system and the hypothalamic pituitary adrenal (HPA) axis may explain the enhanced risk for CVD. To test this hypothesis, 55 patients (34 males and 21 females) with burnout on sickness absence and 40 healthy participants (16 males and 24 females) were exposed to a psychosocial stressor consisting of mental arithmetic and public speech. Physiological variables (i.e., blood pressure, heart rate, cardiac output, vascular resistance, cortisol, and alpha-amylase) were measured. Basal levels, reactivity, and recovery were compared between groups. In male patients, baseline systolic blood pressure was higher, whereas basal alpha-amylase and cortisol reactivity were lower than in healthy males. In female patients, a tendency for lower basal cortisol was found as compared to healthy females. Furthermore, reduced basal heart rate variability and a trend for elevated basal cardiac output were observed in both male and female patients. Burnout is characterised by dysregulation of the sympathetic and parasympathetic system and the HPA axis, which was more pronounced in males than in females. This study further supports burnout as being a risk factor for CVD through dysregulation of the sympathetic and parasympathetic system and the HPA axis.
This finding gave me much food for thought.

“In contrast to prediction, reduced cortisol reactivity to an acute psychosocial stressor was observed in male(burnout) patients, which suggests hyporeactivity of the HPA axis, rather than hyperactivity. Although the simultaneous predominance of the sympathetic system and hyporeactivity of the HPA axis was not predicted, this pattern has been found previously in the context of chronic stress, burnout, and vital exhaustion and gives rise to unfavourable alterations in immune functioning fostering risk for CVD

[4].”