A systematic review of existing medications found that antibiotics and vaccines are associated with a reduced risk of dementia.
Across the 14 studies included in the data analysis, most of which were from the United States, the researchers identified dozens of medications that could be linked to dementia risk — for better or worse.
The study is the largest of its kind, covering more than a million cases of dementia, and while the results aren’t “immediately clear,” there are intriguing trends at play.
Although the associations between certain medications and dementia risk varied widely between studies, certain medications such as antibiotics, antivirals, and vaccines were most commonly associated with a reduced risk of dementia.
Four vaccines in particular, including those that protect against diphtheria, hepatitis A, typhoid, and hepatitis A and typhoid combination, have been linked to a reduction in dementia risk of between 8 and 32 percent.
It’s not clear why, but the international team of researchers notes that viral and bacterial infections appear to be common risk factors for dementia, and “there is growing interest in vaccination as generally protective.”
“Our results support these hypotheses and lend further weight to these agents as potentially disease-modifying or dementia-preventive,” the team concludes.
Their current research only reveals associations, so it can’t tell us what causes dementia or if and how these medications might help prevent it. What it can do, however, is point scientists in the right direction.
Despite decades of research and tens of billions of dollars, only a handful of new drugs have been approved for treating dementia. Aside from a few recent breakthroughs, most of these options only treat the symptoms of the disease, while others come with serious side effects.
As a result, some scientists have turned to already approved drugs to see if they could be repurposed to prevent cognitive decline.
Recently, for example, a drug used to induce labor was shown to protect the aging brains of mice, and in humans, those taking popular diabetes and weight loss drugs, like Ozempic, also appear to have a reduced risk of dementia. .
But it is not easy to sort through the considerable volume of drugs available.
“Bringing these huge health data sets together provides a source of evidence that we can use to help us focus on which medications we should try first,” says senior psychiatrist Benjamin Underwood of the University of Cambridge, who led the recent study with a dementia researcher. Ilianna Lourida from the University of Exeter.
The authors also found that anti-inflammatory medications, such as ibuprofen, may be associated with a reduced risk of dementia. Antihypertensives and antidepressants, on the other hand, have given conflicting results.
Recent studies suggest that dementia may be caused by brain problems due to high blood pressure or chronic inflammation, but more research is needed to determine whether medications that address these problems play a role in decline. cognitive and what is their impact on this risk.
“We hope this will help us find much-needed new treatments for dementia and speed up the process of getting them to patients,” Underwood says.
“If we can find drugs that are already approved for other conditions, we will then be able to put them into trials and, most importantly, we will be able to make them available to patients much more quickly than we would for a completely new drug. new.”
The study was published in Alzheimer’s and dementia: translational research and clinical interventions.
