Detecting Who Will Likely be Sufferers of Alzheimers

Monday, March 19th 2001, 12:00 am
By: News On 6

ST. LOUIS – Patients with certain memory problems, called mild cognitive impairment, are likely to have early Alzheimer's disease, a new study has found.

"Alzheimer's disease and aging aren't the same," said Dr. John Morris, an author of the study, which appears in the March issue of Archives of Neurology. "When we see a deviation from healthy aging, I'm suspicious that it's early Alzheimer's."

If the researchers are right, patients with early signs of the disease may be treated sooner, expanding the $600million-a-year market for Alzheimer's medicines. At the same time, the U.S. Food and Drug Administration is debating whether to let drug makers treat mild cognitive impairment as a separate disorder and target the symptoms with specific medicines.

"In order to spend research dollars, you need an indication," or new treatment category, said Michael Gold, director of clinical pharmacology at Bristol-Myers Squibb, which is developing an Alzheimer's drug that it wants to market for the mild cognitive disorder. Though current medicines are used for signs of mild cognitive impairment, "we can't market for that" without FDA approval, he said.

In the study, researchers tracked 400 volunteers with mild or no memory loss. After 91/2 years, all of the volunteers who had displayed subtle signs of memory loss developed Alzheimer's, the study found.

Patients with mild cognitive impairment, or MCI, fail memory tests such as recalling facts from a paragraph that they read earlier, and have trouble performing tasks that they previously did well, such as completing tax returns.

At least 2.5 million elderly people may have mild cognitive impairment, FDA medical consultants said last week, and some estimated that the number might be higher.

Alzheimer's patients have an advanced form of dementia, a chronic deterioration that causes symptoms including confusion and an inability to carry out basic tasks such as getting dressed. Four million people in the United States have been diagnosed with Alzheimer's, the degenerative brain disease.

Earlier diagnosis may help researchers find ways to slow the progress of the disease.

"Current medications can maintain cognitive ability," Dr. Morris said.

Drug makers packed the FDA meeting room last week in an effort to determine whether the agency will decide mild cognitive impairment can be treated separately from Alzheimer's, greatly expanding the potential market for Alzheimer's drugs.

"I don't think it'll be cost-effective for the industry to push for this claim if it's only going to be for those people who go on to [develop] Alzheimer's," said Dr. Mary Ganguli, a professor of psychiatry and epidemiology at the University of Pittsburgh, and an FDA panel expert. "That's not my experience in the clinic."

If a broader interpretation of MCI were adopted, more patients might accept such a diagnosis because it wouldn't carry the stigma of Alzheimer's, and more people might seek treatment, panel members said.

"We also have to be cognizant of individuals who suffer from these problems," said Dr. Howard Weiner, professor of neurology at Brigham & Women's Hospital in Boston, and an FDA expert. "The stigma, the label of Alzheimer's disease is not a pleasant one, so segregating them can be helpful."

FDA experts said that although studies show that most patients with mild cognitive impairment eventually develop Alzheimer's, a separate category is needed for patients who don't progress to Alzheimer's.