Re: Plotnikoff G, Barber M. Refractory depression, fatigue, irritable bowel syndrome, and chronic pain: A functional medicine case report. Perm J 2016 Fall;20(4):15–242. DOI: https://doi.org/10.7812/TPP/15-242; and Hanaway P. Form follows function: A functional medicine overview. Perm J 2016 Fall;20(4):16–109. DOI: https://doi.org/10.7812/TPP/16-109.
Dear Editor,
In the Fall 2016 edition of The Permanente Journal (TPJ), one case report1 and one editorial2 were published on the topic of functional medicine. As Permanente physicians who aspire to practice medicine in an evidence-based manner, we were surprised to see these articles published in TPJ. Although we understand that TPJ tries to give voice to areas of medicine that are innovative and provide different perspectives, there are several unsubstantiated claims across these articles that we hope will not be broadly incorporated in practice by Permanente physicians.
In his editorial, Hanaway2 provides the following definition of functional medicine:
“Functional Medicine is a systems-biology-based model that empowers patients and practitioners to work together to achieve the highest expression of health by addressing the underlying causes of disease. Functional Medicine uses a unique operating system and personalized therapeutic interventions to support individuals in achieving optimal wellness.”
We certainly agree that approaching our patients in a holistic and caring manner is always best, but we are unaware of a scientific basis for the “unique operating system” and “personalized therapeutic interventions” suggested in these articles. Perhaps accidentally, Hanaway acknowledges that functional medicine does not have an adequate evidence base and relies on unproven suppositions when he writes, “As we move from Case Reports to randomized controlled trials and population-based trials, Functional Medicine research will offer insight into the best ways to improve the value of the care we offer.”2
In the case report, Plotnikoff and Barber1 discuss a 72-year-old man with long-standing depression, fatigue, irritable bowel syndrome, and chronic pain. As primary care physicians, we can envision this patient and many others like him. These are challenging clinical situations without easy answers. Though presenting an N of 1 case report, Plotnikoff and Barber suggest that many patients with multiple chronic conditions would benefit from the functional medicine approach. They propose “seven potential core imbalances” that may serve as the “root” causes of any disease:
Assimilation (digestion, absorption, microbiomics, respiration)
Defense and repair (immune function, inflammation, infection)
Energy (production, regulation)
Biotransformation and elimination (toxicity, detoxification)
Transport (cardiovascular and lymphatic systems)
Communication (hormones, neurotransmitters, cytokines), and
Structural integrity (membranes, fascia, bacterial translocation).
The patient in the case was assessed with a Comprehensive Digestive Stool Analysis 2.0 (CDSA 2.0) and a Nutritional Evaluation (NutrEval) by Genova Diagnostics.a Plotnikoff and Barber1 claim that these tests offer insight into the patient’s functional status with regard to several of the proposed core pathways comprising functional medicine. The patient was diagnosed with vitamin D deficiency, low normal dehydroepiandrosterone-sulfate (DHEAS), pancreatic insufficiency, and persistent Candida glabrata overgrowth in the stool. His treatment included pancreatic enzyme support, probiotics, a diet rich in prebiotiocs, and four weeks of daily fluconazole. Although the case report documents improvement in patient-reported outcomes scores across three scales (Brief Fatigue Inventory, Brief Pain Inventory, and Patient Health Questionnaire-9), attributing this improvement to the multitude of interventions presented in Table 3 of the article, “Stool and urine metabolic testing results and therapeutic interventions,” is dubious. Association is not necessarily causation.
Sackett et al3 provided the classic definition of evidence-based medicine as, “… the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients.” We find it somewhat audacious for Plotnikoff and Barber to quote Sackett in their conclusions. Case reports and suppositions do not represent best evidence, and conclusions based on them are not broadly generalizable to larger groups of patients. In Hanaway’s editorial,2 we noted with interest that randomized controlled trials comparing functional medicine with current standard care are underway at the Cleveland Clinic. But unless and until such clinical trials demonstrate efficacy of the functional medicine approach, we believe TPJ should not encourage Permanente physicians to incorporate functional medicine into clinical practice as it has done implicitly by publishing this case study and editorial.
Sincerely,
Craig W Robbins, MD, Medical Director, Evidence-Based Practice, Care Management Institute, Denver, CO; Meighan Elder, MD, Internal Medicine, Boulder, CO; Michelene A Kuhr, MD, Family Medicine, Boulder, CO; Mark S Hoskinson, MD, Internal Medicine, Boulder, CO
Footnotes
Dr Hanaway was Chief Medical Officer at Genova Diagnostics from 2002–2012.
References
- 1.Plotnikoff G, Barber M. Refractory depression, fatigue, irritable bowel syndrome, and chronic pain: A functional medicine case report. Perm J. 2016 Fall;20(4):15–242. doi: 10.7812/TPP/15-242. DOI: https://doi.org/10.7812/TPP/15-242. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Hanaway P. Form follows function: A functional medicine overview. Perm J. 2016 Fall;20(4):16–109. doi: 10.7812/TPP/16-109. DOI: https://doi.org/10.7812/TPP/16-109. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Sackett DL, Rosenberg WM, Gray JA, Haynes RB, Richardson WS. Evidence based medicine: What it is and what it isn’t. BMJ. 1996 Jan 13;312(7023):71–2. doi: 10.1136/bmj.312.7023.71. DOI: https://doi.org/10.1136/bml.312.7023.71. [DOI] [PMC free article] [PubMed] [Google Scholar]