Shingles Vaccine Linked to Slower Biological Aging in Older Adults

Shingles vaccination not only protects against the disease but may also contribute to slower biological aging in older adults, according to a new USC Leonard Davis School of Gerontology study. Using data from the nationally representative U.S. Health and Retirement Study, researchers examined how shingles vaccination affected several aspects of biological aging in more than 3,800 study participants who were age 70 and older in 2016. Even when controlling for other sociodemographic and health variables, those who received the shingles vaccine showed slower overall biological aging on average in comparison to unvaccinated individuals. The study, "Association between shingles vaccination and slower biological aging: Evidence from a U.S. population-based cohort study," is published in the Journals of Gerontology, Series A: Biological Sciences and Medical Sciences. Shingles, also called herpes zoster, is a painful, blistering skin rash caused by the reactivation of the chickenpox virus, or varicella zoster. Anyone who has had chickenpox is at risk of shingles; while shingles can occur at younger ages, the risk is higher for those 50 and older and immunocompromised individuals. Vaccination, which has generally only been provided to older people, offers protection from shingles as well as a lower chance of postherpetic neuralgia, or long-term pain after a shingles infection. While vaccines are designed to protect against acute infection, recent research has highlighted a possible connection between adult vaccines, including those for shingles and influenza, and lower risks of dementia and other neurodegenerative disorders, said Research Associate Professor of Gerontology Jung Ki Kim, the study's first author. "This study adds to emerging evidence that vaccines could play a role in promoting healthy aging by modulating biological systems beyond infection prevention," she said. Measuring the body, not the calendar Unlike chronological aging, biological aging refers to how the body is changing over time, including how well organs and systems are working. Two people who are both 65 years old may look very different inside: one may have the biological profile of someone younger, while another may show signs of aging earlier. In the new study, Kim and co-author Eileen Crimmins, USC University Professor and AARP Professor of Gerontology, measured seven aspects of biological aging: inflammation innate immunity (the body's general defenses against infection) adaptive immunity (responses to specific pathogens after exposure or vaccination) cardiovascular hemodynamics (blood flow) neurodegeneration epigenetic aging (changes in how genes are turned "off" or "on") transcriptomic aging (changes in how genes are transcribed into RNA used to create proteins) The team also used the measures collectively to record a composite biological aging score. Surprising results beyond shingles prevention On average, vaccinated individuals had significantly lower inflammation measurements, slower epigenetic and transcriptomic aging, and lower composite biological aging scores. The results provide more insight into the possible mechanisms underlying how immune system health interacts with the aging process. Chronic, low-level inflammation is a well-known contributor to many age-related conditions, including heart disease, frailty, and cognitive decline. This phenomenon is known as "inflammaging," Kim said. "By helping to reduce this background inflammation—possibly by preventing reactivation of the virus that causes shingles, the vaccine may play a role in supporting healthier aging," she said. "While the exact biological mechanisms remain to be understood, the potential for vaccination to reduce inflammation makes it a promising addition to broader strategies aimed at promoting resilience and slowing age-related decline." These potential benefits could also be persistent. When analyzing how the time since vaccination affected results, Kim and Crimmins found that participants who received their vaccine four or more years prior to providing their blood sample still exhibited slower epigenetic, transcriptomic and overall biological aging on average versus unvaccinated participants. "These findings indicate that shingles vaccination influences key domains linked to the aging process," Crimmins said. "While further research is needed to replicate and extend these findings, especially using longitudinal and experimental designs, our study adds to a growing body of work suggesting that vaccines may play a role in healthy aging strategies beyond solely preventing acute illness."