Multiple Sclerosis: Communication Breakdown

by Food and Drug Administration (FDA)

Shari Ferko feared the worst when she was diagnosed with multiple sclerosis in 1990. Her ability to walk was declining and she might soon need a cane and eventually a wheelchair, she thought. She wasn't even sure she'd be around to see her children grow up.

"It was a scary prospect," says the Dallas mother of two, whose children were 7 and 8 at the time. "I thought, 'These kids need their Mom. Will I even see them graduate from high school?'"

But Ferko did see her children graduate, and today, at age 48, she chases after a grandchild when she isn't working at a desk job as a nurse three days a week. "I'm still not using a cane and I only use a wheelchair for long distances," says Ferko, who didn't let her disease keep her from touring Europe last year.

Ferko takes medications to help relieve fatigue, spasms, blurred vision, and bowel and bladder problems, all common symptoms of multiple sclerosis (MS).

An estimated 400,000 Americans have MS, according to the National Multiple Sclerosis Society (NMSS). Every week, about 200 people in the United States are diagnosed with the disease. But many are managing their symptoms and staving off debilitation with medications.

Today, five FDA-approved treatments to lessen the likelihood of MS attacks are on the market. Three of them also slow the progression of disability in this often- incapacitating disease.

A Prime-of-Life Disease

MS is a non-contagious, lifelong chronic disease that causes symptoms such as weakness, muscle stiffness, poor coordination and balance, tingling, numbness, tremors, blurred vision, and slurred speech. According to the National Institute of Neurological Disorders and Stroke (NINDS), about half of all people with MS also experience memory and concentration problems.

"It's a disease that strikes people typically in the prime of their life," says Susan McDermott, M.D., an FDA neurologist. In rare instances, it can develop in children or older adults, but MS is diagnosed most frequently in people between the ages of 20 and 50, according to the NMSS.

Ferko's first symptom — loss of vision in one eye — appeared when she was 23. She was diagnosed with inflammation of the optic nerve (optic neuritis), and treatment with steroids restored her sight, she says. It wasn't until five years later that her second symptom appeared — numbness and tingling in one leg. More bouts with optic neuritis and bowel and bladder problems followed, along with mobility problems. "I had a slow, progressive decline in my ability to walk long distances, decreased sensation in my hands, and I would tire easily," says Ferko.

Experts recognize three main forms of MS. In its most common form — relapsing-remitting — an attack, or relapse, is followed by a period of decreased or no symptoms (remission) until the next flare-up. "A relapse can leave some residual disability, or it can resolve completely over the course of weeks or months," says Marc Walton, M.D., Ph.D., a neurologist and director of the FDA's Division of Therapeutic Biological Internal Medicine Products.

A second form of MS — primary-progressive — brings on a gradual decline and disability without specific attacks. In the third form — secondary-progressive — MS starts out as relapsing-remitting but eventually takes on a course of gradual progressive disability with few or no relapses.

MS ranges from a very mild, hardly noticeable disease in some people to a very severe, paralyzing disease in others. About 20 percent of people with MS have a benign form of the disease, according to the NINDS. After the first attack, they show minimal, if any, progression and remain fully functional for long periods of time. "However, a majority of people with MS will go on to eventually have significant disability," says Walton.

Research indicates that despite disability, most people with MS have a life expectancy only a few years shorter than normal.

Communication Breakdown

The exact cause of MS is unknown. "So many things have been implicated," says McDermott. "The general consensus is that most people who have MS have a genetic predisposition to it, but something in the environment triggers it," such as a virus, bacteria, a toxic chemical, or some other agent. "Gender also seems to play a role," says McDermott, "as women are more commonly affected than men."

Although the disease trigger still eludes researchers, they do know that MS interrupts the body's intricate communication network of nerves. In a healthy individual, nerve fibers act like electrical cables, transmitting electrical impulses, or messages, at high speeds between the brain, the spinal cord, and the rest of the body. The fibers are insulated by a fatty coating called myelin.

In a person with MS, experts say the immune system appears to attack the brain and spinal cord. This attack inflames random patches of plaques, causing lesions that destroy the nerve-protecting myelin. Scar tissue replaces the myelin, a process known as demyelination. When electrical impulses zip through the nerve fibers and reach the scarred areas, they "short circuit," slowing or preventing communication.

The loss of myelin "disrupts the way we receive signals, the way we give commands to our muscles to allow us to move, and the integrating activity that the brain and spinal cord needs to process sensory and motor movement information to allow us to function normally," says Stephen Reingold, Ph.D., research counselor and former vice president for research programs at the NMSS. Continued scarring combined with damage to the nerve fibers may result in permanent disability.

About the Author

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