You can find out more about NPF's National Medical Director, Dr. Michael S. Okun, by also visiting the NPF Center of Excellence, University of Florida Center for Movement Disorders & Neurorestoration.
Over the last decade or more, several new therapies have emerged and subsequently been touted as restorative and/or curative for Parkinson’s disease. In many cases, practitioners have offered a substantial fee for each treatment, and they have administered these treatments in an office or hospital setting – sometimes repeating the treatment 30 times or more. Touted therapies, which have fallen into this “curative” category include fee for stem cell infusions, fee for glutathione infusions, and, most recently, fee for chelation. Though there may be reasonable rationales for each of these therapies, scientific evidence is lacking, and chelation should only be administered under institutional review board-approved (IRB) protocols, and only for research purposes. Parkinson’s disease patients should not be paying for chelators, and they should be warned of potential risks of therapy. Past What’s Hot columns have focused on fee for stem cell and fee for glutathione therapies, and this month’s column will address chelation therapies.
Chelation is the process where a chemical forms a connection or complex with a heavy metal, and thereby functionally inactivates it. The word chelate is derived from the Greek word meaning claw. One way to remember what a chelator does is to remember that it simply claws or grabs a circulating metal ion. Chelators can be used to detoxify heavy metals in the body, and are most commonly prescribed for lead, mercury or arsenic poisoning.
Common uses for chelators include root canal treatments and agents used in contrast materials for MRI scanning (gadolinium). Diseases such as hemochromatosis (iron overload) have been treated with the chelator defuroxamine. This particular chelator can be very effective in addressing the iron overload which is known to result in the disease state – however, there may also be potential side effects associated with the drug such as cardiovascular, pulmonary, auditory and ocular issues. Another common chelator that has been used is ethylenediamine tetra-acetic acid (EDTA). EDTA was previously thought to possibly prevent atherosclerotic artery hardening. The mechanism was theorized to act through removal of calcium deposits in blood vessel walls. EDTA therapy has however, been disproven for atherosclerosis. Similarly, EDTA has been turning up on websites and in doctor’s offices as the touted cure for other diseases including Alzheimer’s and Parkinson’s disease – despite a lack of scientific evidence or data from clinical trials. We do not recommend EDTA, or any other chelators for Parkinson’s disease. For those patients who are determined to try EDTA, please remember that using disodium EDTA instead of calcium EDTA has resulted in reported deaths.
The idea of using a chelator for Parkinson’s disease is not completely far-fetched. It is known that iron accumulates in the Parkinsonian brain, and iron seems to accumulate in important brain areas known to be part of the neurodegenerative process – including the substantia nigra. Additionally, there are a few animal experiments that have shown a protective effect of chelation against the development of Parkinson’s disease. It has been hypothesized by many groups that oxidative stress may result in an iron imbalance, and this imbalance may in some way contribute to the brain degeneration seen in Parkinson’s disease patients. However, it remains to be proven that removing iron from the brain of a Parkinson’s disease patient will have any clinically beneficial or disease-modifying effects.
Patients should be wary of any practitioner offering a fee for chelation therapy to treat or to cure Parkinson’s disease. If a practitioner offers to send your blood, urine or hair to an expert (for a fee) in order to demonstrate a link to your Parkinson’s disease, we suggest that you consider declining this offer. Many of the practitioners touting chelation will send the specimens to their own unregulated mail away laboratories, and results will often reveal positive or impossible scenarios – such as elevations in multiple heavy metals (for example, lead, mercury and arsenic are all elevated which is a very unlikely scenario). If you are worried you have a heavy metal toxicity, you should see your neurologist for a comprehensive visit including an exposure history and examination. A good neurologist should be able to detect common heavy metal clinical manifestations, such as neuropathy or unique lines on the finger nails (e.g. Mees lines). Parkinsonian symptoms would represent an uncommon manifestation of heavy metal toxicity, except in the cases of Manganese exposure in miners and in welders. In manganese exposure, the MRI is usually abnormal (as opposed to the relatively normal MRI in Parkinson’s disease, see previous What’s Hot column). A neurologist can also send a urine sample to an approved and credible 24-hour laboratory to test for the presence of heavy metals.
In conclusion, patients should be wary of any clinic performing chelation therapy for Parkinson’s disease. These clinics should only be performing chelation under an IRB-approved research protocol, and patients and insurance companies should not be charged for what would be defined as an experimental therapy. Further, patients should be informed that chelation therapy has many associated risks. The storybook may not be completely closed on chelation therapy for Parkinson’s disease, however scientists and physicians must carry the burden of developing the direct link between iron deposition and neurodegeneration, and in proving that developing a drug that can cross the blood brain barrier and remove the iron will ultimately prove to be a viable and a meaningful treatment approach.
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