New research suggests that both infection control and anti-inflammatory medications may play significant roles in reducing dementia risk, offering potential new avenues for prevention strategies.
Infection Control Shows Promise in Dementia Prevention
A comprehensive evidence review published January 21 in Alzheimer's and Dementia: Translational Research & Clinical Interventions has found that preventing or treating infections could be a key approach to warding off dementia. The review, led by Dr. Benjamin Underwood from the University of Cambridge, examined 14 studies involving more than 130 million people and 1 million dementia cases.
The researchers discovered that vaccines, antibiotics, antiviral medications, and anti-inflammatory drugs were all associated with reduced dementia risk. These findings lend support to theories proposing viral and bacterial infectious causes for common dementias.
"We urgently need new treatments to slow the progress of dementia, if not to prevent it," said Dr. Underwood. "If we can find drugs that are already licensed for other conditions, then we can get them into trials and — crucially — may be able to make them available to patients much, much faster than we could do for an entirely new drug."
The research team initially set out to identify existing drugs that could be repurposed for dementia treatment. While they found conflicting evidence regarding several drug classes including blood pressure medications, antidepressants, and diabetes drugs, the pooled data revealed a consistent association between infection control measures and lower dementia risk.
NSAIDs Show Protective Effects in Long-Term Use
In a separate study published in the Journal of the American Geriatrics Society, researchers from Erasmus MC University Medical Center in Rotterdam found that long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin and ibuprofen was associated with a 12% reduction in dementia risk.
The Dutch study tracked nearly 12,000 healthy participants over an average of 14 years. Among the participants, 81% had used NSAIDs at some point, with 2,091 eventually developing dementia. Importantly, the protective effect was only observed with long-term NSAID use, not with short or medium-term use.
"Our study provides evidence on possible preventive effects of anti-inflammatory medication against the dementia process," said senior researcher Dr. M. Arfan Ikram, chair of epidemiology at Erasmus MC. "There is a need for more studies to further consolidate this evidence and possibly develop preventive strategies."
Interestingly, the researchers found that a person's cumulative dose of NSAIDs did not seem to affect their dementia risk, suggesting that "prolonged rather than intensive exposure to anti-inflammatory medication may hold potential for dementia prevention."
Inflammation's Role in Dementia Pathology
Both studies highlight inflammation as a significant contributor to dementia development. The Cambridge-led review noted that "inflammation is increasingly being seen to be a significant contributor to a wide range of diseases, and its role in dementia is supported by the fact that some genes that increase the risk of dementia are part of inflammatory pathways."
This growing body of evidence suggests that controlling inflammation, whether through direct anti-inflammatory medications or by preventing infections that trigger inflammatory responses, may help protect brain health.
Cautions and Limitations
Researchers from both studies emphasized that their findings show associations rather than definitive cause-and-effect relationships.
"Because a particular drug is associated with an altered risk of dementia, it doesn't necessarily mean that it causes or indeed helps in dementia," explained Illianna Lourida, a research fellow with the University of Exeter who worked on the infection control study.
The Dutch research team specifically cautioned against recommending long-term NSAID treatment for dementia prevention, noting the potential for adverse effects, particularly the increased risk of dangerous bleeding among seniors.
"Although our results are an indication of the important role of inflammation in the treatment of dementia, they do not justify the recommendation of long-term treatment with NSAIDs for the prevention of dementia, given its potential adverse effects," they concluded.
Future Research Directions
Both research teams called for additional studies to further explore these promising findings. The goal would be to develop targeted preventive strategies that maximize benefits while minimizing risks.
As the global burden of dementia continues to grow, with approximately 55 million people currently living with the condition worldwide, these studies offer promising new directions for prevention efforts. By focusing on modifiable risk factors like inflammation and infection, researchers hope to develop effective interventions that could significantly reduce dementia incidence in the coming decades.
For now, experts recommend that patients consult with their healthcare providers before making any changes to their medication regimens, as individual risk factors and health conditions must be carefully considered.
