• No peer-reviewed epidemiological study supports the claim that COVID-19 vaccines increase dementia risk 140-fold compared with flu shots. A 2025 systematic review and meta-analysis of 104 million participants found COVID-19 vaccination was not associated with increased Alzheimer’s disease risk (RR 0.92, 95% CI 0.61–1.39) or vascular dementia risk (RR 1.03, 95% CI 0.55–1.94), while influenza vaccination was linked to reduced dementia risk (RR 0.87, 95% CI 0.77–0.99)¹.
• The Alzheimer’s Society explicitly states there is no evidence that COVID-19 vaccines increase dementia risk or make dementia worse².
• The “140 times” figure appears to originate from a misinterpretation of proportional reporting ratios (PRR ≈ 115–118, upper confidence interval ≈ 156–160) for “cognitive impairment” adverse events in the passive VAERS database, which measures relative reporting frequency, not actual disease incidence or risk³.
• Experts and fact-checkers have repeatedly warned that comparing raw VAERS reports between COVID-19 and influenza vaccines is invalid because of heightened reporting intensity, media attention, lack of denominator data, and unverified causality⁴.
• Therefore, the claim conflates voluntary adverse-event reporting with clinical disease risk and is contradicted by population-level health data.

Overall validity: 0%

1. Association between vaccinations and risk of dementia: a systematic review and meta-analysis
2. Coronavirus (Covid) vaccines and dementia
3. Association between COVID-19 Vaccination and ...
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