Effect of chiropractic treatment on primary or early secondary prevention: A systematic review with a pedagogic approach

Introduction: The chiropractic vitalistic approach to the concept of 'subluxation' as a cause of disease lacks both biological plausibility and possibly proof of validity. Nonetheless, some chiropractors purport to prevent disease in general through the use of chiropractic care. Evidence of its effect is needed to be allowed to continue this practice. The objective of this systematic review was therefore to investigate if there is any evidence that spinal manipulations/chiropractic care can be used in primary prevention (PP) and/or early secondary prevention in diseases other than musculoskeletal conditions. Method: We searched PubMed, Embase, Index to Chiropractic Literature, and some specialized chiropractic journals, from inception to October 2017, using terms including: "chiropractic", "subluxation", "wellness", "prevention", "spinal manipulation", "mortality". Included were English language articles that indicated that they studied the clinical preventive effect of or benefit from manipulative therapy/chiropractic treatment in relation to PP and/or early treatment of physical diseases/morbidity in general, other than musculoskeletal disorders. Also, population studies were eligible. Checklists were designed in relation to the description of the reviewed articles and some basic quality criteria. Outcomes of studies were related to their methodological quality, disregarding results from those unable to answer the research questions on effect of treatment. Results: Of the 13.099 titles scrutinized, 13 articles were included (eight clinical studies and five population studies). These studies dealt with various disorders of public health importance such as diastolic blood pressure, blood test immunological markers, and mortality. Only two clinical studies could be used for data synthesis. None showed any effect of spinal manipulation/chiropractic treatment. Conclusion: We found no evidence in the literature of an effect of chiropractic treatment in the scope of PP or early secondary prevention for disease in general. Chiropractors have to assume their role as evidence-based clinicians and the leaders of the profession must accept that it is harmful to the profession to imply a public health importance in relation to the prevention of such diseases through manipulative therapy/chiropractic treatment.