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By LAURAN NEERGAARD, AP Medical Writer
WASHINGTON - Americans with advanced Alzheimer's disease (news - web sites) soon can try the first treatment proved effective for late stages of the mind-robbing illness.
Memantine should be on pharmacy shelves by January under the brand name Namenda, its marketer says. The drug has been sold for two decades in Germany, desperately sought by many U.S. families since word of its promise began spreading last year.
It was approved Friday by the Food and Drug Administration (news - web sites).
The marketer, Forest Laboratories Inc., says it has been getting over 1,000 calls a month from people waiting to buy it. Others have been buying supplies overseas via the Internet.
Memantine does not offer miraculous benefits, said the FDA, worried about giving families false hope.
The drug can delay worsening from Alzheimer's, however, allowing people to maintain functions such as going to the bathroom independently for a few months longer.
It's the first option specifically for people with moderate to severe Alzheimer's symptoms. Today's other four Alzheimer's medications are proved to work only in early stages of the disease.
Perhaps more importantly, memantine works on a different brain chemical than the other four drugs. That means for the first time, doctors can combine different Alzheimer's therapies in hopes of better results.
Today, some families import memantine from Europe for prices ranging from $147 to $240 for a month's supply. Forest Laboratories, which licensed the drug from German maker Merz Pharmaceuticals, refused to say whether U.S. prices would fall within that range, saying it had not yet decided.
Ruth Hobbs, 74, of Winchester, Ky., has been taking a combination of memantine and the older Alzheimer's drug, Aricept, for about a year in a research project.
A year ago, Hobbs couldn't remember Thanksgiving had even occurred. This year, she's planning to help cook, and her family credits the combination with allowing her to continue living alone.
"We had reached a point where we were saying, `What are we going to do about Mama?'" recalled DeEtta Blackwell, Hobbs' daughter. Now, "we're not waiting for the other shoe to drop."
About 4.5 million Americans have Alzheimer's, and a million of them are believed to suffer severe symptoms. It afflicts mainly the elderly, robbing them of memory and the ability to care for themselves. There is no known cure or prevention; medications only temporarily slow the inevitable worsening.
Memantine has been used in Germany for two decades to treat different brain disorders. In 1999, the first solid research was published that suggested memantine could help moderate to severe Alzheimer's; the drug won Europewide approval for that use last year.
In U.S. studies, some patients experienced improvements in memory and other skills, like Hobbs.
But for most, the drug instead slowed the pace of deterioration, by some measures at half the pace of those given a dummy drug. Performance was measured on cognitive tests and by tracking how well patients performed certain functions such as getting dressed or bathing themselves.
"The effect wasn't overwhelming," cautioned FDA neurologic drugs chief Dr. Russell Katz. "But they did better than they would have done if they hadn't gotten anything."
And for families facing the prospect of round-the-clock care, maintaining even some simple activities for an extra six months is very important, said Zaven Khachaturian, senior science adviser of the Alzheimer's Association.
"Having another one, that operates on a different principle, is welcome news," he said.
The four other Alzheimer's medications — Aricept, Exelon, Reminyl and Cognex — work by delaying the breakdown of a brain chemical called acetylcholine, which is vital for nerve cells to communicate. In contrast, memantine blocks excess amounts of another brain chemical, called glutamate, that can damage or kill nerve cells.
Doctors don't yet know whether memantine works better when given in early stages of Alzheimer's; those studies are under way.
New Way to Test for Alzheimer's Disease
TUESDAY, Sept. 16 (HealthDayNews) -- Determining the ratio of two biochemicals in a person's spinal fluid may help doctors evaluate patients with dementia and diagnose Alzheimer's disease (news - web sites).
The study found the ratio of the phosphorylated tau protein to beta-amyloid peptide42 was much higher in patients with Alzheimer's and was accurate in distinguishing patients with Alzheimer's from healthy people without the disease and patients with non-Alzheimer's dementias and other neurological disorders.
The researchers examined cerebrospinal fluid from 100 people who had a diagnostic evaluation for dementia and from 31 healthy people who served as controls for the study.
The study notes that diagnosing Alzheimer's and distinguishing it from other dementias relies heavily on a doctor's judgment. Diagnostic accuracy of Alzheimer's is less than 80 percent to 90 percent accurate, particularly in the early stages of the disease. The process of diagnosing the disease can be lengthy and costly.
The authors conclude this method of testing may provide a promising tool for diagnosing Alzheimer's. They write that its usefulness may be further evaluated in clinical settings.
Tue Jan 21, 1:22 AM ET Add Health - AP to My Yahoo!
By LINDSEY TANNER, AP Medical Writer
CHICAGO - A variation in a gene that is supposed to help the brain break down cholesterol may play a role in some cases of Alzheimer's disease (news - web sites), researchers say.
A study found that people with this variant form face double the risk of developing late-onset Alzheimer's, the most common form of the disease. It typically develops after age 65.
The gene, called CYP46, is involved in production of an enzyme that helps break down excess cholesterol in the brain. The research suggests that the variation might hamper production of the enzyme, resulting in a buildup in the brain of cholesterol and a gummy protein called beta amyloid.
The research, though preliminary, fits in with growing evidence that elevated cholesterol levels may raise the risk of Alzheimer's.
It also adds to evidence that genetics are involved. Late-onset Alzheimer's already has been linked to another genetic variation in a different gene involved in helping transport cholesterol throughout the body. That variation is called APOE-4.
In the new study, patients with both the CYP46 and APOE-4 variants were almost 10 times more likely to develop the mind-robbing disease than those with neither variation. They also had the highest brain levels of beta amyloid.
Autopsies also showed participants with just the CYP46 variant had significantly more beta amyloid deposits than those without the variant.
Dr. Andreas Papassotiropoulos at the University of Zurich and colleagues studied more than 400 European patients with or without Alzheimer's. The CYP46 variant was found in about 40 percent of participants.
The findings appear in January's Archives of Neurology.
Most of the estimated 4 million Americans with Alzheimer's have late-onset disease. It affects about one in 10 Americans over age 65 and nearly half of those over 85, according to the Alzheimer's Association.
An increasing number of studies suggest that cholesterol plays an important role in regulating beta amyloid.
Studies such as Papassotiropoulos' suggest that inhibiting cholesterol breakdown in the brain "might represent a viable treatment" for Alzheimer's, Dr. Benjamin Wolozin of Loyola University Medical Center in Maywood, Ill., said in an accompanying editorial.
from NEW ENGLAND JOURNAL OF MEDICINE 11/28/2002
ABSTRACT
Background Neurologic abnormalities affecting gait occur early in several types of non-Alzheimer's dementias, but their value in predicting the development of dementia is uncertain.
Methods We analyzed the relation between neurologic gait status at base line and the development of dementia in a prospective study involving 422 subjects older than 75 years of age who lived in the community and did not have dementia at base line. Cox proportional-hazards regression analysis was used to calculate hazard ratios with adjustment for potential confounding demographic, medical, and cognitive variables.
Results At enrollment, 85 subjects had neurologic gait abnormalities of the following types: unsteady gait (in 31 subjects), frontal gait (in 12 subjects), hemiparetic gait (in 11 subjects), neuropathic gait (in 11 subjects), ataxic gait (in 10 subjects), parkinsonian gait (in 8 subjects), and spastic gait (in 2 subjects). During follow-up (median duration, 6.6 years), there were 125 newly diagnosed cases of dementia, 70 of them cases of Alzheimer's disease and 55 cases of non-Alzheimer's dementia (47 of which involved vascular dementia and 8 of which involved other types of dementia). Subjects with neurologic gait abnormalities had a greater risk of development of dementia (hazard ratio, 1.96 [95 percent confidence interval, 1.30 to 2.96]). These subjects had an increased risk of non-Alzheimer's dementia (hazard ratio, 3.51 [95 percent confidence interval, 1.98 to 6.24]), but not of Alzheimer's dementia (hazard ratio, 1.07 [95 percent confidence interval, 0.57 to 2.02]). Of non-Alzheimer's dementias, abnormal gait predicted the development of vascular dementia (hazard ratio, 3.46 [95 percent confidence interval, 1.86 to 6.42]). Among the types of abnormal gait, unsteady gait predicted vascular dementia (hazard ratio, 2.61), as did frontal gait (hazard ratio, 4.32) and hemiparetic gait (hazard ratio, 13.13).
Conclusions The presence of neurologic gait abnormalities in elderly persons without dementia at base line is a significant predictor of the risk of development of dementia, especially non-Alzheimer's dementia.
Source Information
From the Department of Neurology (J.V., R.B.L., C.B.H., G.K., M.J.K., H.B.) and the Department of Epidemiology and Social Medicine (R.B.L., C.B.H.), Albert Einstein College of Medicine, Bronx, N.Y.; and Innovative Medical Research and the Center for Healthier Aging (Advanced PCS), Hunt Valley, Md. (R.B.L.).
Address reprint requests to Dr. Verghese at the Einstein Aging Study, Albert Einstein College of Medicine, 1165 Morris Park Ave., Bronx, NY 10461, or at jverghes@aecom.yu.edu.
Mon Oct 14, 6:11 PM ET
By Linda Carroll
NEW YORK (Reuters Health) - Medications to lower blood pressure may help stave off dementia and Alzheimer's disease (news - web sites), two new studies show.
One, a large European trial, found that anti-hypertensive medications reduced the risk of dementia by 55% among patients who initially had high blood pressure, according to the report published in the Archives of Internal Medicine (news - web sites).
A second study published in the same journal found that blood-pressure lowering drugs were associated with a decrease in the risk of mental decline in elderly African Americans.
"It is important to make the point that, increasingly, the medical-scientific community is recognizing that common cardiovascular risk factors--such as high blood pressure, high cholesterol and diabetes--are predictive not only for the development of vascular dementia, but also for Alzheimer's disease, the more common form of neurodegenerative dementia," Dr. Jan Staessen, the European trial's co-author, said in an interview with Reuters Health. Staessen is a researcher with the University of Leuven in Belgium.
Staessen and his colleagues determined that the drugs protected best against Alzheimer's disease. "The majority of dementia cases prevented would have been Alzheimer's," he noted.
In the European study, researchers followed 2,902 patients, who were originally part of a trial to test the impact of anti-hypertensive medications on the risk of stroke. The patients all were at least 60 years old and had no observable mental impairment.
During the original trial, 1,417 of the patients received a placebo, while 1,485 were treated with blood-pressure lowering medications. At the end of the stroke study, all the patients were allowed to take the blood-pressure lowering medications and researchers continued to monitor all study participants for any decline in mental ability.
The researchers found that mental decline was most common among patients who had been assigned to the placebo group. Among these patients, there were 43 cases of dementia (29 were Alzheimer's), as compared to 21 cases (12 Alzheimer's) among study participants who had been taking anti-hypertensive medications all along.
Findings of the study of African Americans were similar. That study, led by Michael D. Murray, followed 1,900 patients 65 or older who had no signs of mental impairment at the study's outset.
Twice during the course of the five-year study, Murray and his colleagues tested patients' mental abilities and recorded medications patients were taking.
After five years, 288 patients showed some decline in their mental ability.
After factoring in the effects of age, sex, education, initial mental function scores and heart disease, the researchers found that patients who took anti-hypertensive medications were 38% less likely to show declines in their mental abilities. "The results of this longitudinal analysis of long-term drug effects indicate that antihypertensive medications reduce the risk of cognitive impairments in older African Americans," conclude Murray, a researcher with Indiana University School of Medicine in Indianapolis, and colleagues.
Murray and his team didn't speculate as to how the drugs might protect the brain.
And while Staessen and his colleagues aren't yet sure why the blood-pressure lowering drugs help, he's got some ideas.
"Two explanations for our findings are possible," he said. "A small difference in blood pressure persisted during most of the follow-up between patients initially randomized to placebo and active treatment--blood pressures were lower in the active treatment group. So lower blood pressure might explain the better outcome."
But not all studies have shown that anti-hypertensive medications reduce the risk of mental decline, he added. An alternative hypothesis, he said, is that one of the medications, a calcium-channel blocker, might offer specific protection against Alzheimer's disease.
"Laboratory experiments have shown that intracellular calcium plays an important role in causing the death of brain cells," Staessen added. Studies have also shown that the calcium channel blocker used in the study can enter the brain and "bind to receptors in those areas of the brain affected by Alzheimer's disease, and that it can restore the neurotransmitters that become deficient in Alzheimer's."
SOURCE: Archives of Internal Medicine 2002;162.
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None
0
|
Questionable
0.5
|
Mild
1
|
Moderate
2
|
Severe
3
|
|
Memory
|
No memory loss or slight inconsistent forgetfulness
|
Consistent slight forgetfulness; partial recollection of events; "benign" forgetfulness
|
Moderate memory loss; more marked for recent events; defect interferes with everyday activities
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Severe memory loss; only highly learned material retained; new material rapidly lost
|
Severe memory loss;
only fragments remain
|
Orientation
|
Fully oriented
|
Fully oriented except for slight difficulty with time relationships
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Moderate difficulty with time relationships; oriented for place at examination; may have geographic disorientation elsewhere
|
Severe difficulty with time relationships; usually disoriented to time, often to place
|
Oriented to person only
|
Judgment & Problem Solving
|
Solves everyday problems & handles business & financial affairs well; judgment good in relation to past performance
|
Slight impairment in solving problems, similarities, and differences
|
Moderate difficulty in handling problems, similarities, and differences; social judgment usually maintained
|
Severely impaired in handling problems, similarities, and differences; social judgment usually impaired
|
Unable to make judgments or solve problems
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Community Affairs
|
Independent function at usual level in job, shopping, volunteer and social groups
|
Slight impairment in these activities
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Unable to function independently at these activities although may still be engaged in some; appears normal to casual inspection
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No pretense of independent function outside home
Appears well enough to taken to functions outside a family home
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No pretense of independent function outside home
Appears too ill to be be taken to functions outside a family home
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Home and Hobbies
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Life at home, hobbies, and intellectual interests well maintained
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Life at home, hobbies, and intellectual interests slightly impaired
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Mild but definite impairment of function at home; more difficult chores abandoned; more complicated hobbies and interests abandoned
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Only simple chores preserved; very restricted interests, poorly maintained
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No significant function in home
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Personal Care
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Fully capable of self-care
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Needs prompting
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Requires assistance in dressing, hygiene, keeping of personal effects
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Requires much help with personal care; frequent incontinence
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Score only as decline from previous usual level due to cognitive loss, not impairment due to other factors.
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