The Alzheimer’s Disease Association estimates that 4 million Americans have Alzheimer’s disease. Alzheimer's disease (AD) slowly and progressively destroys brain cells and subsequently steals a person's memory, language, thinking, and behavior skills.

Aspirin, ibuprofen, and other non-steroidal anti-inflammatory drugs (NSAIDs) have been used with mixed results to help decrease Alzheimer's symptoms. But now a growing body of evidence suggests that long-term use of these medicines before symptoms are present may delay or prevent the onset of the disease. New research published in the September 23, 2002 issue of Neurology took the research one step further by looking at the influence of duration and timing of taking these drugs on the later development of AD. The results suggested that NSAIDs use for two or more years could delay or prevent AD development, though more research is needed to determine whether these differences are clinically significant.

About the Study

Researchers at Johns Hopkins University in Baltimore, Maryland and the University of Washington in Seattle, Washington studied 3,227 men and women age 65 and older. These participants were residents of Utah who participated in the Cache County Study, an on-going study of the influence of genetic and environmental factors on dementing disorders, like Alzheimer’s.

Interviewers asked participants about their current and past use of prescription or over-the-counter medicine. Then researchers classified participants based on their use of certain types of the drugs. The first drug category contained drugs that previous research suggested might influence AD including aspirin compounds, non-aspirin NSAIDs such as ibuprofen, and Histamine-2 receptor antagonists (H2RA) – a class of drugs that prevent or block the production of stomach acid. The second category included non-NSAID pain relievers such as acetaminophen, simple antacid/anti-gas agents, and other non- H2RA stomach remedies. This group of medications served as the “control” exposure because there was no prior reason to believe these drugs affect Alzheimer’s disease. Participants were only included in one of the categories if they took at least 4 doses per week of the drug for one month or longer.

Over the course of the three-year study, participants were screened and tested for the presence of dementia or Alzheimer’s disease. This included mental screening exams, interviews, neurological and neuropsychological examinations, and tests by trained nurses or technicians. A panel of experts in neurology, geriatric psychiatry, neuropsychology, and cognitive neurology assigned the final diagnosis of Alzheimer’s disease. Researchers compared the number of Alzheimer’s disease cases among users of a given class of medicine versus non-users.

The Findings

In general, there was no significant reduction in Alzheimer’s risk observed between the groups. However, the data did suggest that long-term use of NSAIDs might decrease the risk of developing Alzheimer’s disease by as much as 55%. Results also suggested that a longer duration of use might produce a stronger reduction in risk. These findings parallel the results of three other studies suggesting that sustained use of NSAIDs may only delay or prevent Alzheimer’s disease if taken before damage to brain cells has occurred. Adjusting for age, sex, and education had no significant effect on the results.

Although these results were not conclusive, this study had a number of limitations:

  • Researchers looked only at people who were older than 65 when they entered the study, so the influence of long-term use from a younger age remains unknown
  • There were not enough people taking each class of medication to study the effect of dosage.
  • There was no information collected on, and no adjustments made for, the use of other drugs, diet, exercise, supplement use, and other factors that may have influenced the onset or progression of AD.
  • The various risk and benefit estimates varied widely, which makes it difficult to know what the true effect of each drug was.
  • As with many studies on AD, the early stages of dementia (before diagnosis) can influence a patient’s ability to remember past behaviors (in this case the types and duration of taking several medicines)
  • There is also a very limited ability to apply these results to the general population since over 90% of participants were highly educated and had access to high-quality health care.

How Does This Affect You?

At this time, it does not appear that taking an aspirin a day will necessarily reduce your risk of Alzheimer’s disease. These findings suggest that aspirin and other NSAIDs might help delay or prevent Alzheimer’s disease, but more research is needed to determine what amount and over what period of time these medications may be helpful. If you’re already taking daily low doses of aspirin for its reported cardiovascular benefits, you may be protecting more than just your heart and blood vessels. More research may someday reveal that the aspirin is good for your brain too.

Though it seems that NSAIDs may have beneficial uses outside of pain relief, taking these medications daily is not without risk. Aspirin and other NSAIDs are well known for the harm they can do to the stomach lining, in some cases leading to ulcers. While the vast majority of patients use these medications over long periods of time without incident, you should consult your health care provider before taking them for the purpose of preventing Alzheimer’s disease or any other health condition.