Vaccinations against tetanus and diphtheria, pneumococcus, and herpes zoster (HZ)- better known as shingles, are linked to a reduced risk of Alzheimer's disease (AD). The corresponding study was published in the Journal of Alzheimer's Disease.
Viral, bacterial, and fungal infections increase the risk of neuroinflammation, which may cause or exacerbate neurodegeneration and dementia. Vaccines may thus reduce neurodegeneration and dementia risk by reducing the risk of infection. Previous research, for example, shows that people who receive at least one influenza vaccine are 40% less likely than unvaccinated peers to develop AD.
Currently, the Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) recommends older adults receive vaccines against tetanus, diphtheria and herpes zoster, and pneumococcus. The researchers behind the current study thus sought to see how these common vaccines may affect AD risk.
To do so, they analyzed healthcare data from patients who were dementia-free for two years and then followed for eight years. Patients were at least 65 years old at the beginning of the follow-up period. Ultimately, they found that patients who had been vaccinated for tetanus and diphtheria were 30% less likely than unvaccinated peers to develop AD. Those who had received a herpes vaccination were 25% less likely to develop AD, and those who received a pneumococcal vaccine were 27% less likely to develop the condition.
To put the findings into perspective, senior author of the paper, Paul E. Schulz, MD, the Rick McCord Professor in Neurology with McGovern Medical School, highlighted that three new anti-amyloid antibodies used to treat AD slow disease progression by 25%, 27%, and 35%.
"This research highlights how important it is for patients to have ready access to routine adult vaccinations," said co-first author, Dr. Kristofer Harris, program manager in the Department of Neurology with McGovern Medical School at UTHealth Houston, in a press release.
"Over the last couple of years, the field of Alzheimer's disease has vastly expanded, especially with the recent approval of anti-amyloid antibody medications by the FDA. However, those medications require costly infrastructure in order to be administered safely. Conversely, adult vaccinations are widely available and are already routinely administered as part of a vaccination schedule. Our findings are a win for both Alzheimer's disease prevention research and for public health in general, as this is one more study demonstrating the value of vaccination," he added.
Sources: Science Daily, Journal of Alzheimer's Disease
