Autonomic Balance Differences Through Heart Rate Variability Between Adults with and Without Chronic Low Back Pain.

BACKGROUND

Chronic pain has been reported as one of the leading causes of disability in the world, being associated with a potential impact on autonomic balance.

OBJECTIVE

The aim was to compare sympathetic and parasympathetic activity through heart rate variability (HRV) between adults with and without chronic low back pain (CLBP).

METHODS

An observational study was conducted in which HRV parameters were recorded using time-domain measures-root mean square of successive differences between consecutive RR intervals (rMSSD), minimum and maximum heart rate variability (Min HR and Max HR), and mean heart rate (Mean HR)-and nonlinear measures-Poincaré plot indices SD1 and SD2, Stress Score (SS), and sympathetic/parasympathetic ratio (S:PS).

RESULTS

The results showed statistically significant differences between groups (p < 0.05), with higher parasympathetic activity parameters in the group of healthy subjects (rMSSD: p < 0.001; SD1: p = 0.030) and higher sympathetic activity in the CLBP group (SD2, SS, and S:PS ratio: p < 0.001). All parameters showed large effect sizes.

CONCLUSIONS

These findings show the association between autonomic balance mechanisms and pain regulation in adults with CLBP.