Correlation Between Chronic Neck Pain and Heart Rate Variability Indices at Rest: A Cross-sectional Study.

Objective: The purpose of this study was to correlate the heart rate variability (HRV) indices with variables of pain that were experienced by individuals with chronic neck pain.

Methods: This was a blinded cross-sectional study. Individuals with chronic neck pain (n = 15) and healthy participants (n = 15), both sedentary and between 18 and 45 years of age, were included. The neck pain was assessed with the Numerical Rating Scale at rest and during cervical movements, Neck Disability Index, Catastrophic Thoughts about Pain Scale, and Tampa Scale of Kinesiophobia. The HRV indices (linear and nonlinear) were used for assessment of autonomic function at rest (in supine, sitting, and standing positions).

Results: We observed significant correlations between the NRS, Neck Disability Index, and Catastrophic Thoughts about Pain Scale with the linear and nonlinear HRV indices (P < .05, r ≥ 0.362), so that the worst HRV indices are associated with conditions of more intense and disabling neck pain.

Conclusion: The HRV indices were significantly associated with pain intensity, disabilty, and catastrophizing in individuals with chronic neck pain.