New Therapies Can Ease Cognitive Symptoms for MS Patients

Patients with multiple sclerosis, or MS, can experience a wide array of symptoms, and the severity of their disease can range from relatively benign to disabling. MS affects the central nervous system (brain and spinal cord), disrupting communication to the rest of the body.

In MS, areas of the central nervous system become inflamed in patches called plaques. The nerve covering, called myelin, begins to break down in the affected areas. Myelin helps transmit electrochemical messages between the brain, the spinal cord, and the rest of the body. Where the myelin is damaged, scarring and lesions can develop, slowing or blocking these neurological signals. This results in diminished or lost function, the hallmarks of MS. Symptoms often include:

• Visual disturbances
• Muscle weakness
• Trouble with coordination and balance
• Sensations such as numbness, prickling, or "pins and needles"
• Thinking and memory problems (cognitive symptoms)

Cognitive symptoms occur when lesions develop in brain areas responsible for information processing. The deficits tend to become more apparent as the information to be processed becomes more complex. Fatigue may also add to processing difficulties.

Most MS patients experience muscle weakness in their extremities and difficulty with coordination and balance, according to the National Institute of Neurological Disorders and Stroke. Some notice vision disturbances, such as blurred or double vision, red-green color distortion, or even blindness in one eye. Some have spastic episodes and lack coordination, while others experience bladder and bowel problems. A few MS patients actually have no symptoms.

Multiple sclerosis affects women more often than men. It often begins between the ages of 20 and 40. Usually, the disease is mild, but some people experience rather significant disability. There is no cure for MS, but medicines may slow it down and help control symptoms. Physical and occupational therapy can also help.

Cognitive Problems Common with MS
In The MS Information Sourcebook, the National MS Society estimates that approximately 50% of people with MS will develop some degree of cognitive dysfunction - memory loss, difficulty concentrating, slowness in their thinking speed, and difficulty solving problems. In most cases, however, the dysfunction will not be severe enough to significantly interfere with their daily activities.

Finding therapies to help ease those cognitive disorders is the focus of two research studies at Froedtert & the Medical College of Wisconsin. Julie A. Bobholz, PhD, a Neuropsychologist and Associate Clinical Professor of Neurology, has been actively involved in leading the two studies.

What causes cognitive problems in MS? "The strongest correlate is the disease burden," Dr. Bobholz says. "Risk for cognitive problems depends on the volume of lesions in the brain, the amount of atrophy of brain tissue and to some degree the location of the lesions."

But, she adds, other factors can also trigger such cognitive problems. "Cognitive dysfunction in MS can also be associated with depression, anxiety, stress, sleep disturbance, and fatigue."

Because of the wide variety of symptoms, MS can be difficult to diagnose. No one knows what causes MS, but it's thought that it might be an autoimmune disease, in which the human body begins to attack its own tissues and organs. Initially, patients will undergo a variety of tests to rule out other conditions.

Research Enhances Diagnoses, Treatments
With advances in neuroimaging, notably MRI and fMRI (functional MRI), researchers have learned that when lesions form in the brain, the brain compensates by finding other pathways to perform functions that once originated in the diseased parts, Dr. Bobholz says. "As the lesions reach a certain volume / number, however, the brain cannot compensate, and this leads to impairment in functions."

The two research studies underway at MCW are examining medication options for management of memory and attention problems that occur in MS, says Dr. Bobholz. "At MCW, our research focus is moving towards finding ways to manage the cognitive symptoms that occur with MS.

In one research study, providers at Froedtert & the Medical College Neurosciences Center are examining the effects of Aricept (donepezil hydrochloride), on memory loss in MS. Using functional MRI, researchers can examine a patient's organizational processes and responses to medication while they are performing memory tasks in the MR scanner.

The second study is designed to study the effects of Ritalin (methylphenidate) in patients experiencing MS-related attention problems. Both studies - which are only taking place at Froedtert & the Medical College - are currently enrolling patients. For information about joining either study, patients should call 414-456-4661 to talk to the study coordinator.

Barbara Abel
HealthLink Contributing Writer

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.