Rationale for assessing the effects of manipulative therapy on autonomic tone by analysis of heart rate variability☆☆☆★

Background: For more than 100 years, chiropractors have asserted that overall health can be improved through the use of spinal manipulative therapy. The autonomic nervous system is known to control and regulate all involuntary physiologic activities by controlling the activities of the internal organs, glands, and circulation. Recent studies document a potential relationship between the vertebral subluxation complex, autonomic tone, and cardiac function. Objective: This discussion reviews how it is possible to use heart rate variability analysis to calculate a quantitative index of autonomic function, which accurately reflects the sympathetic and parasympathetic tone and the sympathovagal balance. Discussion: The technique of heart rate analysis known as heart rate variability could be extremely useful in assessment of treatment outcomes in clinical chiropractic practice. At present, heart rate variability is in widespread use in the fields of neurology, cardiology, psychology, psychophysiology, obstetrics, anesthesiology, and psychiatry. Conclusion: Further studies in this area may lead to a better understanding of the effects of spinal manipulation on (1) the general health of an individual, (2) an individual's susceptibility to lowered immunity and recuperative capacity, and (3) conditions that lie outside the scope of musculoskeletal therapeutics and are more in line with classical chiropractic concepts. This can also contribute to a better-informed interprofessional cooperation between allopathic and chiropractic health care providers. (J Manipulative Physiol Ther 1999;22:161–5)