A significant study involving over 130,000 individuals in the United States has revealed a notable association between the shingles vaccine, Shingrix, and the respiratory syncytial virus (RSV) vaccine, Arexvy, and a reduced risk of dementia. The findings suggest a potential protective effect of these vaccines against cognitive decline, marking a promising area for further research in dementia prevention.
The retrospective cohort study, which analyzed electronic health record data, found that older U.S. adults who received the AS01-adjuvanted shingles or RSV vaccines experienced a lower risk of dementia diagnosis within 18 months. Specifically, those who received the RSV vaccine (Arexvy) showed a 29% lower risk of dementia compared to individuals who received the flu vaccine. The shingles vaccine (Shingrix) was associated with an 18% reduced risk.
Researchers hypothesize that the AS01 adjuvant, a component common to both Shingrix and Arexvy designed to boost the immune response, may play a crucial role in this observed protective effect. While the exact immunological mechanisms are still being investigated, the consistent findings across both vaccines point towards the adjuvant's involvement rather than solely the prevention of the target infections themselves, given the short timeframe of the observed effect.
This study builds upon previous research that hinted at a link between the shingles vaccine and reduced dementia rates. However, its large scale and methodology provide stronger evidence for this association. Some theories suggest that certain viral infections, including those prevented by these vaccines, might contribute to dementia risk, making vaccination a potential avenue for prevention.
While these findings are compelling, experts emphasize the need for further clinical and mechanistic studies to confirm the protective effects and understand their duration. As stated by researchers, > "It is likely that both the AS01 shingles and RSV vaccines provide some protection against dementia." The study opens new avenues for understanding dementia pathology and developing novel preventive strategies beyond current interventions.