This article looks at a group of sciatica patients versus a control group measuring HRV.  They contend that standing HRV is more indicative than supine HRV, and that (as in the previous post) nonlinear measures, DFA α 1, are more sensitive.  I am looking at DFA α1 in my project.  In particular, I like to look at the highest and lowest values during a treatment.  I’m wondering if these swings in HRV are indicative of resilience.  It’s still quite rough, so will let you know.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3644230/

Abstract
Background

A chronic pain condition may result in altered autonomic nervous system regulation in various patient populations. We evaluated whether autonomic regulation differs between sciatica patients referred to spine surgery and age-matched healthy controls analyzed with heart rate variability techniques (HRV).

Methods

HRV of patients (n = 201) and healthy controls (n = 138) were measured in standing conditions (5 min). High frequency (HF) power as an index of cardiac vagal modulation and the low-to-high-frequency (LF/HF) ratio and short-term fractal scaling exponent α1 as indices of sympathovagal balance were analyzed. Pain intensity was assessed on a Visual Analog Scale (VAS) and perceived disability with Oswestry Disability Index.

Results

The Oswestry and VAS scores were higher in the patients than in the controls (p < 0.0001 for both). HF power was markedly lower for the patients compared to the controls (p < 0.0001). The LF/HF ratio and α1were higher in the patients than in the controls (p < 0.01 for both). After adjusting for sex, smoking, BMI, and leisure-time physical activity, HF power (p = 0.011) and α1 (p = 0.012) still differed between the groups. Among the patients, HF power was slightly associated with the duration of chronic pain (r = −.232, p = 0.003).

Conclusions

Sciatica patients referred to spine surgery had altered cardiac autonomic regulation expressed as decreased vagal activity and an increased sympathovagal balance toward sympathetic dominance when compared with age-matched healthy controls.