How a Shingles Shot May Guard Against Dementia

New evidence suggests that AS01-based vaccines, beyond their established role in preventing shingles and respiratory syncytial virus (RSV), may also reduce the risk for dementia. The supportive data, published on June 25 in the journal npj Vaccines, underscores the importance of maintaining up-to-date immunizations, particularly among older adults. 

1. Dementia risk dropped after AS01 vaccines.
Patients who received the shingles (Shingrix) or RSV (Arexvy) vaccines — both containing the AS01 adjuvant — had a significantly lower risk for dementia over 18 months compared to those who received the flu vaccine, with an 18% lower dementia diagnosis rate for shingles vaccine and a 29% lower rate for RSV vaccine.

2. Even greater protection when both vaccines were used.
Receiving both AS01 vaccines was linked to a 37% reduced dementia risk, suggesting a possible additive effect.

3. It’s the adjuvant, not the vaccine itself.
The consistent protective signal observed in both shingles and RSV vaccine populations points to the AS01 adjuvant as the probable key factor.

4. What’s in AS01? A powerful immune combo.
The adjuvant includes MPL and QS-21, known to affect brain inflammation and Alzheimer’s-related alterations. MPL stimulates immune cells, while QS-21 enhances the immune response.

5. More research needed, but promising.
Experts stress that these are observational data and short-term, but the research adds weight to the growing case for broader vaccine benefits, including possible brain protection.

Bottom line: While it’s too early to change clinical practice, these findings hint that adjuvanted vaccines like Shingrix and Arexvy may do more than prevent infections; they might help guard against dementia, too.