A review of data from over 23,000 people finds no evidence that low-dose aspirin or other non-steroidal anti-inflammatory drugs can prevent dementia.

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A round-up of existing evidence finds no proof that aspirin protects against dementia.

There is currently no medication that can prevent or delay the onset of dementia. The World Health Organization (WHO) estimate that 50 million people are currently living with dementia globally and that this figure will triple by 2050.

The most common form of dementia is Alzheimer’s disease. However, there are several other forms of dementia, including vascular dementia, which can occur following a stroke, and Parkinson’s dementia, which occurs in some cases of Parkinson’s disease. Some people may experience mixed dementia, which is where various forms occur at the same time.

Researchers are searching for an effective preventive treatment to stem the rising tide of dementia diagnoses, and recent research has pointed towards existing anti-inflammatory drugs.

Several previous studies have suggested that low-dose aspirin, for example, could prevent the onset of Alzheimer’s disease.

However, a recent review of the evidence finds no evidence that aspirin or any other non-steroidal anti-inflammatory drugs (NSAIDs) can prevent dementia.

In contrast, the review warns that the regular use of these drugs could do more harm than good due to an increased risk of bleeding and gastrointestinal problems.

The review follows a growing body of research that suggests that the inflammation around the amyloid plaques and tau tangles seen in people with Alzheimer’s disease could contribute to the onset of dementia.

Based on these and other findings, some scientists hypothesize that drugs such as aspirin might block harmful inflammatory processes in the brain and stop dementia from developing.

Several clinical trials have assessed whether the regular use of common anti-inflammatory drugs could help prevent the onset of dementia.

This review evaluated the evidence from these trials, including data from a total of 23,187 participants. The researchers analyzed four trials in total, one involving aspirin and three involving other NSAIDs.

The trials evaluated the ability of anti-inflammatory drugs to prevent dementia in cognitively healthy people and prevent symptoms worsening in people who were already experiencing cognitive decline.

The trial assessing aspirin’s benefit included over 19,000 older adults and compared low-dose aspirin (one daily dose of 100 milligrams) to a placebo.

The trial found no difference in the rates of dementia between the two groups. However, people allocated to the aspirin group had higher mortality rates and major bleeding events than the placebo group.

The remaining three trials looked at celecoxib (Celebrex), naproxen (Aleve), and rofecoxib (Vioxx). These are NSAIDs that doctors often prescribe to treat arthritis.

Together, these trials included 4,073 people, including healthy older adults with a family history of Alzheimer’s disease, older people with age-related memory loss, and older people with mild cognitive decline (which is often a precursor to Alzheimer’s disease).

None of the trials found any evidence that NSAIDs prevent dementia. In fact, more participants in the rofecoxib group developed dementia than in the placebo group.

All the trials ended early due to side effects that included stomach bleeding and other gastrointestinal problems, such as pain, nausea, and gastritis.

Based on these findings, the reviewers say there is no evidence that aspirin or other NSAIDs prevent dementia. They add that these drugs could be dangerous if a person consumes them regularly due to the increased risk of bleeding.

“This review found no evidence to support the use of either aspirin or other NSAIDs for the prevention of dementia and, in fact, there was some suggestion that they might cause harm.”

– Jordan et al.

The review suggests that there is no need for further trials of aspirin for dementia prevention and that any additional studies of NSAIDs should be mindful of the safety issues.

It is important to note that while this review found no evidence for the use of certain anti-inflammatory agents in the prevention of dementia, it does not show that inflammation is not part of the disease process. Research in this area is ongoing, with several promising results described recently.