Abstract
This study describes the credentials and scope of training of physician and nonphysician practitioners working for US companies marketing unproven stem cell procedures.
More than 700 US clinics advertise unproven stem cell treatments.1 Hematopoietic stem cell transplants to treat various hematologic disorders are evidence-based whereas most other stem cell interventions are investigational. This study examined the characteristics and scope of training of clinicians performing unproven stem cell procedures.
Methods
Through systematic internet searches and content analysis, a 2016 study identified 351 US companies marketing unproven stem cell procedures provided at 570 clinics. The largest concentrations of companies were in California, Florida, and Texas.2 Focusing on companies in these 3 states and identified in the 2016 study,2 we excluded companies that ceased marketing stem cell procedures by January 2018. From company websites, we extracted information related to characteristics and training of all identified professionals. For physicians, we examined state medical board licensing databases to confirm qualifications and compared information obtained from the Federation of State Medical Board (FSMB) Physician Data Center (PDC). The PDC contains specialty board certifications from the American Board of Medical Specialties (ABMS), whereas most information in state medical board databases is self-reported. When discrepancies were found, information from the PDC was used.
To determine scope of training, 2 coders with medical expertise (W.F. and J.F.) used their judgment to independently review conditions each company claimed to treat and determined whether at least 1 physician at the company had the appropriate residency or fellowship training required to treat such conditions. Given the prevalence of companies treating orthopedic indications with stem cells, we compared orthopedic with nonorthopedic facilities using a 2-sided χ2 test calculated using JMP Pro14 (SAS Institute Inc), with a P < .05 considered statistically significant. Companies were classified as orthopedic if they exclusively treated orthopedic conditions based on the ABMS Guide to Medical Specialties3 and the judgment of both coders. Coders recognized that different specialists could treat the same conditions. Generalists were considered not to have specialty training to administer advanced stem cell procedures. Coders were in all cases able to reach agreement concerning company classification and scope of training.
Results
Of 183 identified companies, 166 continued to advertise in 2018. In total, 608 clinicians were identified, of whom 401 (66%) were physicians. Physician assistants, nurses, and complementary and alternative medicine practitioners were the most common nonphysicians (Table 1). Five companies were staffed completely by podiatrists, 2 by naturopaths, 1 by dentists, and 1 by practitioners with unclear qualifications. Forty percent of companies were solo practices; 27% had 2 to 3 practitioners; 14%, 4 to 5 practitioners; and 19%, 6 or more practitioners.
Table 1. Professional Backgrounds of Physicians and Nonphysicians Providing Stem Cell Interventions in California, Florida, and Texas.
| Profession | Individuals, No. (%) |
|---|---|
| Physicians | |
| Doctor of medicine | 338 (55.6) |
| Doctor of osteopathy | 56 (9.2) |
| Medical degree (eg, MBBS) from non-US schools | 7 (1.2) |
| Total physicians | 401 (66.0)a |
| Nonphysicians | |
| Physician assistants | 55 (9.0) |
| Nurses | 34 (5.6) |
| Complementary and alternative medicine practitioners | 32 (5.3) |
| Podiatrists | 29 (4.8) |
| Physical therapists | 18 (3.0) |
| Otherb | 13 (2.3) |
| Scientists with a master’s degree or doctorate in philosophy | 10 (1.6) |
| Unclear qualifications | 10 (1.6) |
| Dentists | 6 (1.0) |
| Total nonphysician clinicians | 207 (34.0) |
| Total clinicians | 608 (100) |
Mean age of 55 years (range, 32-97 years). Mean licensed years of practice of 25 years (range, 2-61 years).
Includes respiratory therapists, estheticians, clinical laboratory technicians, athletic trainers, radiology practitioner assistants, and support staff.
Among the 401 physicians, 91.5% were male and 80.5% completed medical training in the United States. Physicians represented 20 different types of residencies, including orthopedics (30.8%), anesthesiology (15.9%), physical medicine and rehabilitation (10.8%), and family medicine (10.4%) (Table 2). Physicians completed training in 25 different fellowships, including orthopedics (28.5%), sports medicine (24.3%), and pain medicine (21.8%) (Table 2).
Table 2. Residency and Fellowship Training of Physicians Offering Stem Cell Interventions in California, Florida, and Texas.
| Specialty | No. (%) | |
|---|---|---|
| Residencies | Fellowships | |
| Addiction medicine | 2 (0.8) | |
| Anesthesiology | 66 (15.9) | 2 (0.8) |
| Cardiology | 5 (2.1) | |
| Colon and rectal surgery | 2 (0.8) | |
| Cosmetic surgery | 7 (2.9) | |
| Critical care | 2 (0.8) | |
| Dermatology | 5 (1.0) | |
| Emergency medicine | 4 (1.0) | 2 (0.8) |
| Family medicine | 43 (10.4) | 1 (0.4) |
| Gastroenterology | 1 (0.4) | |
| General surgery | 20 (4.8) | 4 (1.7) |
| Geriatrics | 2 (0.8) | |
| Internal medicine | 25 (6.0) | |
| Interventional radiology | 1 (0.4) | |
| Neurological surgery | 16 (3.9) | 4 (1.7) |
| Neurology | 3 (0.7) | 1 (0.4) |
| Obstetrics and gynecology | 6 (1.4) | 1 (0.4) |
| Occupational medicine | 1 (0.2) | 1 (0.4) |
| Ophthalmology | 1 (0.2) | |
| Orthopedics | 128 (30.8) | 68 (28.5) |
| Otolaryngology | 11 (2.7) | 2 (0.8) |
| Pain medicinea | 52 (21.8) | |
| Pathology | 3 (0.7) | |
| Pediatrics | 4 (1.0) | |
| Plastic surgery | 20 (4.8) | 7 (2.9) |
| Physical medicine and rehabilitation | 45 (10.8) | 6 (2.5) |
| Radiology | 9 (2.2) | 5 (2.1) |
| Rheumatology | 1 (0.4) | |
| Sleep medicine | 2 (0.8) | |
| Sports medicineb | 58 (24.3) | |
| Urology | 4 (1.0) | |
| Vascular surgery | 1 (0.2) | |
Pain medicine fellowships were primarily physicians trained in anesthesiology and physical medicine and rehabilitation.
Sports medicine fellowships were primarily physicians trained in orthopedics and family medicine.
Of the 157 companies with a physician, 81 companies (52%) that advertised stem cell treatments had at least 1 physician with formal training matching the conditions claimed to treat. Among orthopedic-focused practices, 68 (77%) had 1 or more physicians with appropriate specialty training. Only 13 companies (19%) that marketed stem cells for nonorthopedic indications had physicians practicing within their scope of training (P < .001).
Discussion
Many clinicians provided stem cell interventions for conditions outside their scope of training. Unlicensed stem cell interventions pose risks.4 Clinicians practicing beyond their scope of training could increase risks to patients.5
This study has several limitations. The analysis was limited to clinicians from 3 states and did not include clinicians who entered the marketplace after 2016. Assessing scope of training relied on coders’ judgment based on residency and fellowship training and did not consider that some physicians may have additional training. Scope of training was underestimated because it was defined at the company level.
In 2018, the FSMB6 reported that 17 of 51 boards investigated complaints, and 8 took disciplinary actions related to physicians’ performing unlicensed stem cell procedures. State medical boards should consider investigating licensees suspected of violating professional standards when providing unproven stem cell interventions, especially those advertising treatment outside their scope of training.
Section Editor: Jody W. Zylke, MD, Deputy Editor.
References
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