Many long COVID symptoms resemble those of postural orthostatic tachycardia syndrome (POTS), but those patients did not meet the diagnostic criteria for POTS, according to an abstract presented in April at the AAN Annual Meeting.
The study included 50 patients from a large COVID recovery clinic who underwent standard autonomic testing at UT Southwestern Medical Center. Before the testing, all patients were evaluated with supine and standing orthostatic vitals and completed symptom questionnaires, the study authors wrote.
Of the 50 long COVID patients, only six met heart-rate criteria for POTS by tilt table; 10 had mild, non-specific autonomic impairment; eight had mildly abnormal testing attributable to medication effects; and 24 had normal testing. One had severe diffuse autonomic failure with neurogenic orthostatic hypotension, and three had mild length-dependent sudomotor impairment.
Lead author Meredith Bryarly, MD, an assistant professor of neurology at UT Southwestern Medical Center, said many of the symptoms reported in long COVID resemble symptoms of POTS, including fatigue, orthostatic intolerance, cognitive impairment, brain fog, and syncope.
“Because the symptoms were so similar to POTS, I was surprised that there were not more post-COVID patients who met the diagnostic criteria for POTS," she wrote in an email. “Also, a subset of POTS patients report an infection prior to developing symptoms. It seemed reasonable to me that a viral infection like COVID could precede POTS as well. As we saw more and more patients referred from the post-COVID clinic, it became clear that the post-COVID patients were a more diverse group than what we see in POTS."
Dr. Bryarly said patients with POTS are predominantly young women, but the group with post-COVID had a much larger age range;those with post-COVID had symptoms for one to two years while many POTS patients report symptoms for 10 years or longer.
Although the research group presented data on 50 patients to the American Autonomic Society meeting in November 2022, it later expanded the study to 80 patients and presented those findings at the AAN Annual Meeting. The researchers also are collaborating with Dr. Nathaniel M. Robbins, an assistant professor of neurology at Dartmouth Hitchcock Medical Center, as that center has done similar testing on a number of post-COVID patients.
Nizar Souayah, MD, FAAN, professor of neurology and neurosciences at Robert Wood Johnson Medical School and the Neurological Institute of New Jersey at Rutgers New Jersey Medical School in Newark, said the two conditions have a lot in common, and it reflects what he sees in his patients. While 24 patients had normal test results, he noted, it was important to note that more than half had abnormal results.
“The autonomic dysfunction in COVID is not coming as a single factor, but it is a combined set of issues—numbness and tingling, a little bit of depression, fatigue, cognitive impairment—it's a whole package," said Dr. Souayah, who also is founding director of the Comprehensive COVID-19 Neurology Care Center of Excellence. “Their perception is different from other patients."
“While our data has shown that only a small subset have POTS (15 percent), a similar therapeutic approach may be beneficial in treating some of the post-COVID symptoms," wrote Dr. Bryarly. “Namely, a focus on non-pharmacologic interventions—good hydration, increased salt intake, avoidance of triggers, graduated exercise protocol, compression garments—as these interventions can be helpful in treating orthostatic intolerance, fatigue, and syncope."
Drs. Bryarly and Souayah had no disclosures.