Yale University study focused on people with self-reported symptoms.
A new study shows some of the most common chronic symptoms among people who began experiencing the problems after receiving a COVID-19 vaccine.
The most common symptoms were exercise intolerance, excessive fatigue, numbness, brain fog, and neuropathy, researchers reported in the paper.
Insomnia, palpitations, myalgia, tinnitus, headache, burning sensations, and dizziness were also experienced by at least half of the participants in the study, which was funded in part by the U.S. National Institutes of Health (NIH).
Participants reported a median of 22 symptoms, with a ceiling of 35.
The study focused on people “who report a severe, debilitating chronic condition following COVID-19 vaccination” that “began soon after COVID-19 vaccination and persisted in many people for a year or more,” the researchers said.
The study was led by Dr. Harlan Krumholz of the Department of Internal Medicine at the Yale School of Medicine and Yilun Wu of the Yale School of Public Health’s Department of Biostatistics.
It was published on Nov. 10 as a preprint ahead of peer review.
Methods
The paper comes from Yale’s Listen to Immune, Symptom and Treatment Experiences Now (LISTEN) research, which examines both so-called long COVID and post-vaccine adverse events.
Researchers began recruiting participants in May 2022. Participants filled out a survey, and researchers had access to their health records.
The study featured adults who reported post-vaccination problems from May 2022 through July 2023. The 388 people who also reported so-called long COVID, or lingering symptoms after COVID-19 infection, were excluded. Another 146 people who didn’t completely fill out the survey were also ultimately left out.
The median age of the participants was 46, and 80 percent were female. Approximately 88 percent live in the United States.
The design of the study means no causality could be confirmed, the researchers said. While they acknowledged the chronic symptoms could be caused by the vaccines, they alleged they could also be unrelated and have occurred by change, but also said the clustering of symptoms soon after vaccination “suggests a potential relationship.”
Known side effects of the vaccines include heart inflammation, severe allergic shock, and Guillain-Barré Syndrome.
