A meta-analysis by researchers at St. Peter’s University Hospital in New Brunswick, New Jersey, found women were more affected than men by new-onset thyroid diseases, such as Graves’ disease and subacute thyroiditis, following COVID-19 mRNA vaccination.

by John-Michael Dumais The Defender

This article was published on The Defender—Children’s Health Defense News & Views Website on May 14, 2024.

COVID-19 mRNA vaccines can cause a low but notable risk of new-onset thyroid diseases, according to a meta-analysis conducted by researchers at Saint Peter’s University Hospital in New Brunswick, New Jersey.


Vikram Gill, a medical doctor and co-author of the meta-analysis, shared the study via poster presentation at the American Association of Clinical Endocrinology annual meeting May 9-11, according to MedPage Today. The study was published in the May issue of Endocrine Practice.

The study analyzed 77 cases of thyroid-related autoimmune diseases among people with no prior history of autoimmune disorders before receiving an mRNA COVID-19 vaccine.

The meta-analysis identified 38 cases of Graves’ disease and 39 cases of subacute thyroiditis among the 77 total cases of new-onset thyroid diseases following vaccination.

Women were more affected than men by a ratio of approximately 2:1. This aligns with the general trend of women being more susceptible to autoimmune diseases compared to men, the authors noted.

The average age of men diagnosed with post-vaccination autoimmune diseases was around 44. For women, it was approximately 41.

Graves’ disease is an autoimmune disorder that causes hyperthyroidism, a condition in which the thyroid gland produces excessive amounts of thyroid hormones. The immune system mistakenly attacks the thyroid gland, leading to inflammation and overproduction of thyroid hormones.

Common symptoms include weight loss, rapid heartbeat, irritability and eye problems (known as Graves’ ophthalmopathy or orbitopathy).

Subacute thyroiditis—also known as de Quervain thyroiditis—is a temporary inflammatory condition of the thyroid gland. It typically presents with a painful, tender, and enlarged thyroid gland, along with symptoms of hyperthyroidism such as weight loss, rapid heartbeat and heat intolerance.

As the inflammation subsides, patients may experience a period of hypothyroidism before the thyroid function returns to normal.

About 80 percent of people in the U.S. have received at least one dose of the COVID-19 vaccine, with about 70 percent considered fully vaccinated, according to CDC data compiled by USA Facts.

Acquired Through MGN Online on 01/20/2016

Onset of Graves’ occurred about 40 days after first vaccine dose

To conduct the meta-analysis, Gill and his co-author Dr. Hongxiu Luo searched for articles reporting Graves’ disease and subacute thyroiditis cases following COVID-19 mRNA vaccinations from 2019 to November 2023.

The study revealed that the onset of Graves’ disease occurred approximately 40 days after the first vaccine dose, while subacute thyroiditis emerged sooner, around 11 days post-vaccination.

More than half of the patients with Graves’ disease developed hyperthyroidism symptoms after the first dose, while nearly 45% showed symptoms after the second dose. Only about 5% exhibited signs following the third dose.

Similarly, in the subacute thyroiditis group, almost 54% presented with hyperthyroidism symptoms after the first dose, roughly 44% after the second dose, and approximately 5% after the third dose.

The meta-analysis also investigated the presence of anti-thyroid peroxidase (anti-TPO or TPO antibodies) and antithyroglobulin (anti-Tg antibodies) in patients with subacute thyroiditis. Anti-TPO and anti-Tg are autoantibodies that target the thyroid gland and are often associated with autoimmune thyroid disorders.

Out of 32 patients tested, only five (15.6%) were positive for anti-TPO, while the remaining 32 patients (74.4%) were negative. Additionally, 11 out of 33 patients tested (33.3%) were positive for anti-Tg and 22 patients (66.6%) were negative, wrote Gill and Luo.

Authors: Results don’t mean ‘vaccines are not efficacious or are dangerous’

Gill emphasized the importance of provider awareness about the potential link between COVID-19 vaccines and autoimmune diseases, stating that “the incidence is highest for the first dose.”

Samarth Virmani, an independent expert from Houston Methodist Hospital who was not involved in the study, described the meta-analysis as “interesting” and highlighted its potential to inform future vaccine development.

“While COVID now is somewhat in the past, this kind of study will help act as a basis for future vaccines that may come out in future pandemics,” Virmani told MedPage Today.

The meta-analysis contributes to the growing body of research exploring the potential links between COVID-19 vaccination and autoimmune disorders.

“Our study doesn’t mean that these vaccines are not efficacious or are dangerous,” Gill said. “It just means that these autoimmune diseases may rarely emerge.”

This article was originally published by The Defender—Children Health Defense News & Views Website under Creative Commons license CC BYNC-ND 4.0.0.