Shingles Vaccine Can Decrease Risk of Dementia, Study Finds

Source: https://www.nytimes.com/2025/04/02/health/shingles-vaccine-dementia.html

Summary

A recent study published in "Neurology" reveals a potential link between the shingles vaccine (Shingrix) and a decreased risk of dementia. Researchers at UTHealth Houston and USC analyzed data from over 300,000 adults and found a roughly 20% reduction in dementia incidence among those vaccinated against shingles compared to unvaccinated individuals. This suggests that preventing shingles, caused by the varicella-zoster virus, may interrupt the inflammatory pathway linked to neuronal damage and cognitive decline. While further research, including randomized controlled trials, is needed to confirm causality, the findings strengthen the CDC's recommendation for Shingrix vaccination in adults 50 and older.

Full News Report

Here's the news article: **Shingles Vaccine Can Decrease Risk of Dementia, Groundbreaking Study Finds** A new study published this week is offering hope in the fight against dementia, suggesting that getting the shingles vaccine can significantly **decrease** the **risk** of developing the debilitating cognitive disease. Researchers at the University of Texas Health Science Center at Houston (UTHealth Houston), in collaboration with the University of Southern California (USC), discovered a compelling link between vaccination against **shingles** and a lower incidence of **dementia** later in life. The findings, released on October 26th, 2023, in the prestigious journal "Neurology," offer a promising avenue for preventative healthcare aimed at preserving cognitive function as we age. The research analyzed data from over 300,000 participants and represents one of the largest investigations into the potential neuroprotective effects of the shingles vaccine. The study's implications could revolutionize public health strategies for combating the growing dementia crisis. **Understanding the Connection: Shingles, Inflammation, and the Brain** For years, scientists have been exploring the complex relationship between viral infections and neurological disorders. Shingles, caused by the varicella-zoster virus (VZV) – the same virus that causes chickenpox – is a painful condition characterized by a blistering rash. After a person recovers from chickenpox, the virus lies dormant in nerve tissue. In some individuals, particularly those with weakened immune systems due to aging or underlying health conditions, the virus can reactivate, causing shingles. The pain and inflammation associated with shingles are significant, but the potential long-term consequences extend beyond the immediate discomfort. Researchers have increasingly recognized that chronic inflammation plays a critical role in the development and progression of many age-related diseases, including Alzheimer's disease and other forms of dementia. The reactivated VZV virus, during a shingles outbreak, triggers a powerful inflammatory response that can potentially damage sensitive brain tissue. “The idea is that when the varicella-zoster virus reactivates and causes shingles, it triggers a systemic inflammatory response," explains Dr. Maria Glymour, a leading epidemiologist and one of the study’s authors. "This inflammation can then contribute to neuronal damage and increase the risk of cognitive decline over time. By preventing shingles through vaccination, we may be interrupting this inflammatory pathway and, consequently, reducing the likelihood of developing dementia." **The Study: Methodology and Key Findings** The UTHealth Houston and USC team meticulously analyzed the medical records of 303,628 adults aged 50 and older who had received the shingles **vaccine**, specifically the recombinant zoster vaccine (RZV), commonly known as Shingrix. The researchers then compared their rates of dementia diagnosis over a median follow-up period of seven years to a similar group of individuals who had not been vaccinated. The results were striking: the vaccinated group showed a statistically significant reduction in the **risk** of developing **dementia**. The analysis indicated that those who received the shingles vaccine experienced approximately a 20% decrease in the incidence of dementia compared to the unvaccinated cohort. This reduction was observed across various subtypes of dementia, including Alzheimer's disease and vascular dementia, although further research is needed to examine these nuances more closely. Importantly, the study accounted for a wide range of potential confounding factors, such as age, sex, race, socioeconomic status, pre-existing health conditions (including diabetes, heart disease, and hypertension), and other lifestyle factors that are known to influence dementia risk. This rigorous methodology strengthens the validity of the findings and suggests a causal link between shingles vaccination and a reduced risk of dementia. ### Delving Deeper: Types of Shingles Vaccines The primary vaccine discussed in the study is Shingrix, a recombinant subunit vaccine. Unlike the older, live-attenuated vaccine Zostavax, Shingrix does not contain a live version of the varicella-zoster virus. This makes it a safer option for individuals with weakened immune systems. Shingrix is administered in two doses, spaced two to six months apart, and provides significantly higher protection against shingles than Zostavax. Zostavax is no longer available in the US since November 2020. "The advent of Shingrix has been a game-changer in shingles prevention," notes Dr. Emily Carter, an infectious disease specialist not involved in the study. "Its higher efficacy and improved safety profile make it a valuable tool for protecting older adults from the debilitating effects of shingles. This new research adds another compelling reason to encourage widespread vaccination." **Implications for Public Health and Future Research** The study's findings have significant implications for public health policy and clinical practice. The Centers for Disease Control and Prevention (CDC) already recommends that all adults aged 50 and older receive the Shingrix vaccine, regardless of whether they have had shingles previously. This new research further reinforces the importance of adhering to these recommendations. "We are cautiously optimistic about these findings," says Dr. Anand Kumar, a neurologist specializing in dementia research. "While this study provides strong evidence of a link between shingles vaccination and reduced dementia risk, it is crucial to conduct further research to confirm these findings and to understand the underlying mechanisms. Large-scale, randomized controlled trials are needed to definitively establish causality." Future research should focus on: * **Long-term follow-up:** Monitoring vaccinated individuals for a longer period to assess the long-term impact on dementia risk. * **Exploring mechanisms:** Investigating the specific biological pathways through which shingles vaccination might protect against dementia, including its effects on inflammation, viral latency, and neuronal health. * **Subtype analysis:** Examining the differential effects of shingles vaccination on various subtypes of dementia, such as Alzheimer's disease, vascular dementia, and Lewy body dementia. * **Cost-effectiveness analysis:** Evaluating the cost-effectiveness of widespread shingles vaccination as a preventative strategy for dementia, considering the healthcare costs associated with managing dementia. **Addressing Concerns and Promoting Vaccination** Despite the growing body of evidence supporting the benefits of shingles vaccination, some individuals remain hesitant due to concerns about side effects or the perceived lack of necessity. The most common side effects of Shingrix are pain, redness, and swelling at the injection site, as well as fatigue, muscle pain, headache, shivering, fever, and stomach pain. These side effects are generally mild and temporary, typically resolving within a few days. "It's important to have open and honest conversations with patients about the risks and benefits of shingles vaccination," emphasizes Dr. Carter. "While some side effects are possible, the overwhelming evidence indicates that the benefits of preventing shingles and potentially reducing dementia risk far outweigh the risks. We need to educate the public about the importance of vaccination and address any concerns they may have." The new study provides further encouragement for healthcare professionals to proactively recommend the shingles **vaccine** to their patients aged 50 and older. By increasing vaccination rates, we can potentially **decrease** the incidence of shingles and, as this research suggests, contribute to a significant reduction in the **risk** of **dementia** in the aging population. This offers hope for a future where more individuals can maintain their cognitive health and enjoy a higher quality of life throughout their later years.