Painkillers such as ibuprofen that are widely used for headaches and arthritis may also reduce the risk of Alzheimer's disease, a degenerative, fatal disorder for which there is little treatment.
The link has been reported before, but a study published in today's issue of the journal Neurology is the first to analyze a large number of patients over a long period of time. The study was conducted by researchers from the Johns Hopkins University and the National Institute on Aging.
They found that people taking nonsteroidal anti-inflammatory medications for as little as two years had half the risk of Alzheimer's disease as those not taking the drugs. Acetaminophen, which has no anti-inflammatory activity, was found to have no effect on Alzheimer's risk. Aspirin, a potent anti-inflammatory agent, appeared to have little or no effect, but scientists believe that may be because the dosages were too low.
"This is a very promising area of research, and it's an area that we should move on very quickly, given how important this disease is and the profound impact it can have on society, particularly as the baby boomers age," said Dr. Walter F. Stewart, lead author on the study and an adjunct professor of epidemiology at the Hopkins School of Public Health.
"The medical care costs associated with Alzheimer's are just overwhelming, let alone the personal trauma," he said.
But Stewart and other physicians are urging people not to begin taking the medicines in hopes of preventing Alzheimer's. Instead, they are recommending the link first be explored in a clinical trial to establish proof.
For the report published today, researchers analyzed the medical data on 1,686 people from 1980 to 1995, looking at what medicines they took and for how long. They drew from the Baltimore Longitudinal Study of Aging, a program in which physicians have examined 2,300 area residents and collected all kinds of medical data since 1958. Because information has been accumulated over years into a database, and it hasn't been skewed by specific research theories, the information is considered much less biased than other data.
'Very significant study'
"It's a very significant study, and it really illustrates the power of this group that we have in Baltimore," said Dr. Paul Fishman, professor of neurology at the University of Maryland Medical School and chairman of the medical and scientific advisory board for the local Alzheimer's society.
During the time covered by the study, use of nonsteroidal anti-inflammatories tripled among participants. Ibuprofen accounted for nearly half of this type of painkiller, with Naprosyn following at 15 percent, and a variety of other prescription and over-the-counter drugs making up the rest.
There are side effects to chronic painkiller use. Doctors identified peptic ulcers and impaired kidney function, and said others might emerge in the trial.
The report brings optimism to families struggling with an illness that attacks the brain and leaves relatives unable to speak, walk or feed themselves.
"Maybe I've been doing something good for myself, and I don't even know it," said Mary French, an Annapolis woman who takes ibuprofen every day for arthritis. Her mother died of Alzheimer's at age 75 a year ago, and French, 52, has long feared she would face the same fate. She has even knitted baby clothes for future grandchildren, in case she becomes ill before they are born.
As her mother's caregiver for five years, French said, she discovered the dementia of Alzheimer's put them through trials worse than other relatives endured with cancer and heart disease.
"You watch their mind slowly slip away from you every day, and you watch what their body goes through. They can't walk, they start falling, they're very frightened, afraid to go out of the house," she said. "They don't become children, but they become helpless as children."
American society spends $100 billion annually on Alzheimer's disease.
According to the Alzheimer's Association, it is the third-most-expensive illness, after heart disease and cancer, and the fourth leading cause of death in adults. Four million Americans have the disease, and as many as 100,000 a year die from it.
But so far, only two drugs are on the market. Both relieve symptoms of Alzheimer's, but they do not prevent the disease and do little to slow its progression.
The new finding grew from earlier research in animals and other studies, as well as the thinking that inflammation may be a key to the Alzheimer's disease process. While the mechanism is unclear, scientists have some theories about what may be happening.
As people age, nerve cells generate an abnormal protein called amyloid in small amounts. In the brains of people with Alzheimer's, there are larger deposits of amyloid. These deposits may be poisonous to the cells. The immune system may try to get rid of the deposits, a response that could trigger the inflammation seen in patients' brains.
Others theorize that the inflammatory cells may actually be processing the amyloid and creating toxins, said Dr. Peter J. Whitehouse, director of the Alzheimer's Center at University Hospitals of Cleveland and a neurology professor at Case Western Reserve University.
"There are a number of different components of the inflammation that may be playing a role," Whitehouse said.
In any case, researchers speculate that the nonsteroidal anti-inflammatory medicines may interfere with this process, thereby lessening the harmful effects.
Collaborating with Stewart on the study were Dr. Claudia Kawas and Maria Corrada, both of the Johns Hopkins School of Medicine, and Dr. E. Jeffrey Metter of the National Institute on Aging.
Pub Date: 3/10/97