An OHSU doctor studies how multiple sclerosis attacks the brain's ability to store, organize and recall data
By Oz Hopkins Koglin of The Oregonian staff
Jonathan Harris concentrates on a magazine article about multiple sclerosis, a disease he's had for 22 years. This is his third reading of the article, not only because it is interesting but because he is struggling to retain what he's read.
"I lose track," said the 39-year-old former firefighter.
Multiple sclerosis is best known for causing physical disability, but Harris found out the hard way that MS sometimes affects the brain's ability to store, organize and recall information.
That startling realization came when Harris was no longer physically able to fight fires and he went back to school to study for a new career in business. A top-ranking student when he was studying in college to be a firefighter, Harris discovered MS was affecting his memory and ability to process information. Originally his goal was to graduate in three years, but he was not keeping up with his classes and finally had to quit.
"Something happens to your ability to find the things that are in your mind and relay them to others," Harris said.
Cognitive problems are a common but hidden symptom of multiple sclerosis that is underrecognized by many people, including doctors, said Dr. Dennis N. Bourdette, director of the Multiple Sclerosis Center of Oregon at Oregon Health Sciences University.
The fact is that 10 to 15 years after onset, more than 50 percent of MS patients will be unemployed because they become disabled, usually because of cognitive, not physical impairment, Bourdette said.
He was co-author of a recent drug study that brought the mental complications of MS to light while offering hope that cognitive impairment might be slowed in some patients.
The study, published in the December issue of the Annals of Neurology, showed that patients with relapsing multiple sclerosis were almost 50 percent less likely to worsen cognitively compared with those who did not receive the drug Avonex.
Most patients have the relapsing form of MS characterized by irregular cycles of attacks followed by periods of remission. There is no cure for MS, but Avonex is one of a relatively new group of drugs on the market to slow progression of physical symptoms.
In the study, the drug appeared also to be most effective in slowing decline of a patients' ability to focus, sustain and shift attention, particularly when information was presented rapidly; and it decreased the chances of decline in a patients' ability to learn information and remember it later.
Multiple sclerosis is a chronic, often disabling disease of the central nervous system that interferes with the brain's ability to send and receive messages.
It is thought to be caused by an immune system reaction in which the body's defense system mistakenly attacks the insulation around nerve cells and is replaced by scar tissue. The scar tissue can block or distort nerve signals. Cognitive dysfunction occurs when MS damages certain areas of the brain, scientists say.
Twice as many women as men develop MS, and most often it affects people between the ages of 20 and 40. An estimated 400,000 Americans have multiple sclerosis, about 5,600 of them in Oregon and Clark County, Wash., according to the National Multiple Sclerosis Society, Oregon Chapter.
Cognitive impairment is subtle, and that is probably why it is more likely to be noticed by health professionals who treat a large number of MS patients than by physicians who see an occasional MS patient, said Muriel D. Lezak, OHSU professor of neurology who led the behavioral, social and cognitive measurements part of the Avonex study.
"These patients have difficulty keeping in mind two things at once," Lezak said. "They can do one thing at a time well. If they do it in a quiet room with no interruptions, it may get missed by physicians" who aren't familiar with cognitive symptoms of the disease.
Sometimes patients have to lead the way in informing physicians of their cognitive problems, but many are intimidated and ashamed because they feel they are getting stupid, said Lance Christian, a social worker and program coordinator for the National Multiple Sclerosis Society, Oregon Chapter.
"When I talk to people I like to emphasize it is not that their intelligence is decreasing, it is just that the brain is becoming more inefficient in terms of processing," Christian said.
Cognitive dysfunction can create many difficulties for MS patients and their families, but health professionals at the OHSU program and the National Multiple Sclerosis Society, Oregon Chapter, recommend some general coping strategies. They include:
He considers himself fortunate that his cognitive deficits are few, so far, compared with some MS patients he meets in his support group, where he is a co-facilitator.
"They forget to turn the stove off; forget they left something in the oven. I have never had those problems," Harris said.
But a lot of people with MS will drive down the road and suddenly have to pull over because they forgot where they are or where they are going, he said.
Harris has not had that happen to him.
"I can take care
of my kids. I'm still able to drive."
You can reach Oz
Hopkins Koglin at 503-221-8376 or by e-mail at email@example.com