Heart rate variability is the measure of specific changes in time between successive heart beats. Current research suggests that low heart rate variability is associated with aging, decline, illness, and mortality. In a study involving 15 chronic neck pain patients and 15 healthy controls, researchers found that neck pain patients are more likely to exhibit low heart rate variability, particularly if they reported higher levels of pain intensity and disability. Further study is needed to determine how heart rate variability plays a role in neck pain or vice versa.

Journal of Manipulative and Physiological Therapeutics, June 2019