Pre-print study cited to falsely link COVID vaccines to Parkinson's and Alzheimer's diseases

What is the claim? 

Social media users have been circulating a 2024 study from South Korea, claiming that COVID-19 vaccines are linked to a sharp increase in diseases such as Alzheimer's and Parkinson's. The People’s Voice published an article with the headline "Study Concludes COVID Jabs Make People Ret****d (intellectually disabled)'" that has been widely shared in this context. 

The claims made on social media (Source: X/Facebook/Modified by Logically Facts)

According to a Facebook post, a Japanese neuroscientist, Dr. Hiroto Komano, discussed this study, asserting that mRNA vaccines negatively impact brain function, potentially leading to cognitive diseases like dementia and Alzheimer’s. Similar claims were echoed across other platforms like X (formerly Twitter). Archived versions of similar posts can be accessed here, here, and here.

The article referenced in the claim was published by The People’s Voice, a platform previously fact-checked by Logically Facts for disseminating misinformation and conspiracy theories. The article (archived here) cites an interview with Dr. Hiroto Komano, purportedly a prominent Japanese neuroscientist, who referenced a study conducted in South Korea purportedly demonstrating that mRNA vaccines are detrimental to brain health.

This interview with Dr. Komano (archived here) has been widely shared on social media, reinforcing claims that COVID-19 vaccines have adverse effects on cognitive function. The interview includes slides from a supposed study titled "A potential association between COVID-19 vaccination and development of Alzheimer's disease," where Komano claims a significant increase in mild cognitive impairment (MCI) among vaccinated individuals compared to those who are unvaccinated. Archived versions of social media posts sharing this interview are accessible here, here, and here.

However, this claim is false. The study referenced in the video interview and The People’s Voice article has not undergone peer review and remains in the pre-print stage. Furthermore, it does not establish a definitive connection between COVID-19 vaccines and a heightened risk of neurodegenerative diseases such as Alzheimer’s or Parkinson’s.

What we found 

The study referenced in both the article and the video interview was published in the Quarterly Journal of Medicine (QJM), an international medical journal. Conducted by four researchers—Jee Hoon Roh, M.D., Ph.D., Inha Jung, Yunsun Suh, and Min-Ho Kim, Ph.D.—in Seoul, South Korea, it was released on May 28, 2024. The study aimed to investigate the potential connection between "COVID-19 vaccination and the onset of Alzheimer’s Disease (AD) and its early stage, mild cognitive impairment (MCI)."

The study involved a sample of 558,017 individuals aged 65 or older randomly selected from a 50 percent sample. It established two groups: vaccinated and unvaccinated participants. According to the 'Results' section, the paper acknowledges that no significant relationship was found with vascular dementia or Parkinson’s disease. It does not assert or substantiate a link between COVID-19 vaccines and these neurodegenerative conditions.

The study concludes by highlighting the need for further research into "potential links" between COVID-19 vaccination and increased incidences of Alzheimer’s disease and MCI.

Screenshot of the study and its results. Source: QJM.

It's critical to note that the 2024 study has not undergone peer review and remains in the pre-print stage. Peer review plays a crucial role in evaluating the accuracy and originality of scientific research and ensuring the integrity of published data. Pre-print manuscripts are preliminary versions of scientific papers shared publicly before undergoing peer review.

The Alzheimer’s Society in the United Kingdom has stated that there is no evidence that COVID-19 vaccines impact dementia or contribute to its development. Additionally, a peer-reviewed 2022 study published in the British Medical Journal (BMJ) found no increased risk of rare neurological events following COVID-19 vaccination and emphasized the need for continued research in this area.

The World Health Organization and other studies maintain that COVID-19 vaccines effectively protect against severe illness, hospitalization, and death caused by the virus.

Logically Facts has previously fact-checked claims published by The People's Voice, which can be accessed here, here, and here. 

The verdict

A pre-print paper lacking peer review has been inaccurately cited to claim that COVID-19 vaccines are associated with a significant increase in diseases like Parkinson's and Alzheimer's. The study itself does not assert a definitive link between the vaccines and these diseases, emphasizing the necessity for further research to establish any potential connection.

The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19, including symptoms, prevention, and available treatment, please refer to the World Health Organization or your national healthcare authority.