Antibiotics, vaccinations and anti-inflammatory drugs found to lower risk of dementia

Dementia remains one of the most pressing public health challenges of our time. Its economic burden exceeds $1 trillion globally, with devastating impacts on individuals and caregivers.

Existing treatments are limited, focusing only on symptoms with modest effectiveness. New findings, however, suggest promising avenues in drug repurposing, shedding light on innovative ways to address this complex condition.

Alzheimer’s disease (AD) stands out among dementias due to its prevalence and severe impact. Reducing the onset of AD by even five years could lower its prevalence and associated costs by 40%. Recent advancements, such as the drugs lecanemab and donanemab, represent significant progress.

These medications target amyloid plaques in early symptomatic stages, yielding statistically significant clinical benefits. However, they address only one pathway in a multifaceted disease and carry substantial risks of severe side effects. A broader, multifaceted approach is necessary.

Dementia encompasses various pathological mechanisms, including protein misfolding, inflammation, and disrupted cellular pathways. Targeting these common mechanisms may yield treatments effective across multiple dementia types. This comprehensive approach requires exploring new drugs and repurposing existing ones, especially those with established safety profiles.

Repurposing existing drugs can accelerate clinical trials and reduce costs, making new treatments more accessible. For instance, some diabetes medications have been linked to lower dementia risks, independent of their glucose-lowering properties. However, associations between medications like benzodiazepines and dementia risk remain contested, reflecting the complexity of drug interactions with dementia-related pathways.

Data-driven approaches offer a promising path forward. Large-scale studies leveraging clinical datasets, such as the UK Biobank and electronic health records, allow researchers to identify associations between prescribed drugs and dementia risk.

These methods have identified potential candidates for repurposing, including antibiotics, antivirals, and anti-inflammatory drugs. For example, the BCG vaccine for tuberculosis has been linked to reduced dementia risk, supporting hypotheses that infections may trigger common dementias.

A systematic review by researchers from Cambridge and Exeter provides critical insights into drug repurposing for dementia. The study analyzed data from over 130 million individuals, including one million dementia cases, across 14 large-scale studies. Despite some inconsistencies, the findings identified several drug classes associated with altered dementia risk.

Notably, antibiotics, antivirals, and vaccines were linked to reduced dementia risk, reinforcing the idea that infections may play a role in its development. Anti-inflammatory drugs, such as ibuprofen, also showed promise, highlighting inflammation’s significant role in dementia’s pathology. Inflammation-related genes often intersect with those implicated in dementia, further supporting these findings.

Some blood pressure medications, antidepressants, and diabetes drugs were also associated with changes in dementia risk. However, the evidence remains conflicting, likely due to differences in study methodologies and variations within drug classes.

For instance, some medications target specific biological pathways, while others act more broadly, complicating risk assessments.

The increasing availability of large health datasets enables more sophisticated analyses of drug-dementia associations. By examining hundreds of drugs across millions of patients, researchers can identify patterns and generate hypotheses for further investigation. This reverse approach—starting with real-world data and moving to laboratory studies—offers unique advantages.

Pooling data across studies minimizes publication bias and allows for the replication of findings. Consistent patterns across diverse datasets strengthen confidence in potential drug candidates. For example, studies linking anti-inflammatory drugs to reduced dementia risk are more compelling when replicated across multiple datasets.

Researchers are also developing dementia risk prediction models using these datasets. These models incorporate various factors, including medication use, to identify individuals at higher risk and inform prevention strategies.

However, interpreting these associations requires caution, as underlying conditions often confound results. For instance, diabetes itself increases dementia risk, complicating analyses of diabetes medications.

The UK government is supporting the development of an Alzheimer’s trial platform to streamline the evaluation of potential treatments. This initiative aims to accelerate the testing of repurposed drugs and facilitate their approval for clinical use.

Dr. Ben Underwood of the University of Cambridge emphasizes the importance of repurposing existing drugs: “If we can find drugs that are already licensed for other conditions, we can get them into trials and — crucially — make them available to patients much faster.”

Systematic reviews play a crucial role in this process, pooling evidence from multiple studies to draw more robust conclusions.

Dr. Ilianna Lourida from the University of Exeter highlights the importance of considering both benefits and risks when evaluating potential treatments. She cautions against changing medications without consulting healthcare professionals, emphasizing that observed associations do not necessarily imply causation.

Despite challenges, the use of existing drugs offers a promising strategy to address dementia. By leveraging large datasets and advanced analytical methods, researchers can identify new opportunities for prevention and treatment. As the understanding of dementia’s complex mechanisms deepens, these efforts hold the potential to transform care and improve outcomes for millions worldwide.

The quest for effective dementia treatments continues to evolve, driven by innovative approaches and interdisciplinary collaboration. Combining insights from large-scale data, laboratory research, and clinical trials, researchers are uncovering new possibilities for tackling this global challenge.

While the journey remains complex, the progress made so far offers hope for a future where dementia’s impact is significantly reduced.

Note: Materials provided above by The Brighter Side of News. Content may be edited for style and length.

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