Research published Monday has confirmed a link between Covid infection and a debilitating heart condition called POTS, or postural orthostatic tachycardia syndrome, that has been diagnosed in some patients with long-term Covid.
The findings, published in the journal Nature Cardiovascular Research, are consistent with previous reports from doctors that Covid can cause POTS, an autonomic nervous system disorder often characterized by rapid heartbeat, low blood pressure, fainting and dizziness.
Doctors often don’t recognize the condition, experts say, because it can be confused with a host of other health problems, including anxiety and dehydration. Many patients spend years trying to get the right diagnosis.
One of the earlier discoveries with long covid was that it can be linked to POTS and this new research builds on that, said lead study author Dr. Alan Kwan, a cardiologist at Cedars-Sinai Medical Center.
POTS was also linked to a lesser extent to Covid vaccination with an mRNA vaccine, according to the new study.
Researchers analyzed data from nearly 300,000 patients from Cedars-Sinai Health System in Los Angeles County from 2020 to 2022 who either received at least one dose of a Covid vaccine or had a confirmed case of Covid. The vast majority of people vaccinated in the study received an mRNA vaccine — from Pfizer-BioNTech or Moderna. People with a confirmed case of Covid were not vaccinated.
While the researchers found a small but increased risk of POTS after Covid vaccination and the first dose in particular, the risk was greater after a Covid infection itself: Getting Covid was linked to a five times greater risk of POTS than vaccination.
“The main message here is that while we see a possible link between Covid-19 vaccination and POTS, preventing Covid-19 through vaccination is still the best way to reduce your risk of developing POTS,” said Kwan.
He added that the study has limitations, including that the results were based on patient data from a single health system. He also said the link between POTS and Covid vaccination needs to be confirmed with further studies.
It’s unclear why the Covid vaccines would cause the condition, Kwan said, but added it may be related to the immune response generated by the injections.
Dr. Ofer Levy, the director of the Precision Vaccines Program at Boston Children’s Hospital, agreed.
He noted that the Pfizer and Moderna vaccines have been associated with a small risk of myocarditis. That condition, he said, may also be related to the immune response generated by the injections. Yet the risk of myocarditis is significantly higher after a Covid infection than after vaccination.
Researchers need to investigate immune responses to injections further, because “the better we understand how the side effects work, the smarter we can get at designing better vaccines in the future,” Levy said.
Other vaccines have also been linked to POTS in early reports, but further research has not established a causal relationship.
The HPV vaccine Gardasil, for example, was thought to cause POTS based on early reports, but later reviews found that it didn’t, said Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center, who was not involved in the new research.
However, the link between an infection – including Covid – and POTS is more established.
“Many conditions can cause POTS, including viral infections such as SARS-CoV-2, the virus that causes Covid-19,” Dr. Bala Munipalli, a physician who heads the Post-Acute Sequelae of Covid Clinic at the Mayo Clinic in Jacksonville, Florida, said in an email.
POTS after other types of infections isn’t uncommon, Schaffner said. The condition has been linked to a number of viral or bacterial infections, including the flu, mononucleosis, and Lyme disease.
Dr. Daniel Dudenkov, a physician at the Mayo Clinic, said that while Covid vaccines may be linked to POTS, it’s important to keep in mind that a Covid infection itself is more likely to lead to POTS.
“Vaccines remain an important strategy to fight Covid and its consequences,” he said.
Schaffner agreed, saying the post-vaccination event is “rare.”
“The risk of this happening is much higher with Covid than with the vaccine. So please get vaccinated,” he said.
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