Association between vaccinations and risk of dementia: a systematic review and meta-analysis
Bibliographic record
Abstract
IMPORTANCE: Dementia is a highly prevalent issue in older people. Whilst the prevention of dementia is a public health priority, the role of vaccinations is still largely unexplored. OBJECTIVE: The aim of this systematic review is to evaluate whether common adult vaccinations are associated with a reduced risk of dementia. DATA SOURCES: PubMed, Embase and Web of Science were searched from inception to 1 January 2025. STUDY SELECTION: Observational studies comparing dementia and mild cognitive impairment incidence between vaccinated and unvaccinated adults aged ≥50 years. DATA EXTRACTION AND SYNTHESIS: Four reviewers independently extracted data and assessed study quality using the Newcastle-Ottawa Scale. Risk ratios (RRs) and 95% confidence intervals (CIs) were pooled using a random-effects model. MAIN OUTCOMES AND MEASURES: Incidence of dementia, including its subtypes. RESULTS: Twenty-one studies (n = 104 031 186 participants) were included. Vaccination against herpes zoster was associated with a reduced risk of any dementia (RR 0.76, 95% CI 0.69-0.83) and Alzheimer's disease (RR 0.53, 95% CI 0.44-0.64). Influenza vaccination was linked to a reduction in dementia risk (RR 0.87, 95% CI 0.77-0.99), as was pneumococcal vaccination (RR 0.64, 95% CI 0.47-0.87) for Alzheimer's disease. Tetanus, diphtheria, pertussis (Tdap) vaccination was also associated with a significant reduction for any dementia (RR 0.67, 95% CI 0.54-0.83). CONCLUSIONS AND RELEVANCE: Adult vaccinations, particularly against herpes zoster, influenza, pneumococcus and Tdap, are associated with a lower risk of dementia. Vaccination strategies should be incorporated into public health initiatives for dementia prevention. REGISTRATION: https://osf.io/x3d4f/.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.014 | 0.041 |
| Meta-epidemiology (narrow) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.019 | 0.034 |
| Bibliometrics | 0.006 | 0.007 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.003 | 0.002 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.002 | 0.002 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".