Medical commentator John Campbell, Ph.D., analyzed a South Korean peer-reviewed study that found statistically significant increases in the incidence of Alzheimer's disease and mild cognitive impairment in people who received a COVID-19 vaccine — particularly mRNA vaccines — within three months of post-vaccination.

A South Korean peer-reviewed study found statistically significant increases in the incidence of Alzheimer's disease and mild cognitive impairment in people who received a COVID-19 vaccine — particularly mRNA vaccines — within three months of post-vaccination.

The South Korean researchers — who on May 28 published their findings in QJM: An International Journal of Medicine — said they undertook the study due to concerns of COVID-19 vaccine side effects, "particularly potential links to neurodegenerative diseases such as Alzheimer's disease."

Medical commentator John Campbell, Ph.D., who analyzed the study on a July 22 episode of his YouTube show, asked why Western countries such as the U.S. or U.K. aren't investigating such potential links. "Why is it often the Asian countries that seem to be leading the way in openness on this?"

According to Campbell, part of what's preventing Western countries is that governments and pharmaceutical companies have refused to release low-level participant data. "Could it be that researchers in the West are working under limitations?"

In the South Korean study, researchers analyzed data from the Korean National Health Insurance Service from more than half a million residents of Seoul, South Korea, age 65 and older.