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Ask the Doc: Q & A with Edward Kasarskis, MD, PhD Edward Kasarskis, M.D., Ph.D. is Director of the multidisciplinary ALS Center at the University of Kentucky Neuroscience Center in Lexington, Kentucky, professor in the Department of Neurology at the University of Kentucky, and Chief of Neurology at the VA Medical Center in Lexington KY.
Q: We just heard on the evening news that there are new drugs for the treatment of multiple sclerosis. Could any of these medications benefit an ALS patient? A: The short answer to your question is, unfortunately, no. But to understand why, it's important to know more about the differences between multiple sclerosis (MS) and ALS. People with ALS and their families often ask me whether these diseases - which both have the word "sclerosis" in their name - are similar. They both affect the central nervous system (the brain and spinal cord) and both can cause significant paralysis, immobility and severe disability. So superficially, they might appear to be in the same family of diseases and hence, respond to the same drugs. MS is an autoimmune disease that causes damage to nerves through the body's own immune defense system turning on itself. The body's immune cells attack the myelin sheath, the protective covering that surrounds the axons of nerve cells. When this nerve covering is damaged, the electrical nerve signals that usually connect one part of the brain to another slow down, or even stop. Think of this as an electrical "short-circuit" within the central nervous system. If the electrical signal is stopped, the message never gets through, and the intended action never occurs. With ALS, the pathways from the brain to the spinal cord also show "sclerosis," but it's because the nerve cells themselves and their connecting axons have degenerated and disappeared. Both involve what can be called "hardening" or sclerosis (loss of the myelin wrapping) but by two completely different mechanisms. With MS, the symptoms can come and go, often with long periods of few or no symptoms at all. With ALS, clear progressive weakness is the norm. Most people with MS will continue to walk and function with minimal disability for 20 or more years after they develop the disease with proper treatment. Some of the symptoms of MS can mimic ALS: muscle spasms, problems moving arms or legs, difficulty walking, weakness, muscle spasms, and trouble speaking, chewing and swallowing. MS tends to affect women more frequently than men, while ALS is the opposite. MS is typically diagnosed earlier in life, between 20 and 40, while ALS most often is diagnosed in the 60's. When neurologists are deciding whether a person has MS, they can find more definitive results from testing (e.g., an MRI) to confirm the diagnosis compared to ALS. For example, a person with MS may have white blood cells, evidence of chemical breakdown of myelin, and excess antibodies in the spinal column, identified through a spinal tap. Frequently, one can actually see the loss of myelin on the MRI scan in MS. The medications used to slow the progression of MS include interferons (such as Betaseron®), Copaxone®, and sometimes methotrexate or other chemotherapy approaches. They're all used to reduce the autoimmune attack that is the cause of dysfunction in MS. The new drugs that you heard about on the evening news are unlikely to help people with ALS; they all are designed to modulate the immune system at one level or another. There have been attempts to assess the impact chemotherapeutic agents and other immune therapies have on ALS, but they were found to not be effective in stopping the progression of the disease. There is little evidence that these drugs work for people with ALS. It is still the goal of research that one day we will have similarly effective drugs for ALS as we now do for MS. If you would like to submit questions for a future Q & A, please send your questions to alsinfo@alsa-national.org. Please understand that we won’t be able to address all questions and we won’t be able to respond to individuals personally. |
