Researchers from the Karolinska Institutet have identified increased odds of postural orthostatic tachycardia syndrome (POTS) in patients with long COVID, publishing their findings in Circulation: Arrhythmia and Electrophysiology on September 30, 2025.1
POTS was reported in approximately 1 in 3 patients with severe long COVID, vs under 1% of the general Swedish population prior to the COVID-19 pandemic. This highlighted a need to screen for POTS in patients with long COVID experiencing significant increases in heart rate while changing position from lying down to standing or during exertion.1
Key takeaways:
- Researchers from the Karolinska Institutet found POTS in approximately 31% of patients with severe long COVID.
- The condition was significantly more common in younger women, suggesting sex-specific vulnerability.
- Patients with POTS showed reduced physical activity and shorter walking distances during exercise tests.
- Simple, inexpensive tests such as the head-up tilt and Active Stand Test can help detect POTS in long COVID patients.
- A prior JAMA Internal Medicine study linked female sex, older age, and high BMI to increased long COVID risk.
“Previous, smaller studies have shown that there is a connection, but now we can say with certainty that POTS is a very common condition in patients with long COVID. This is valuable knowledge for both health care professionals and patients,” said Mikael Björnson, PhD student at the Karolinska Institutet.1
POTS evaluation
The study was conducted to evaluate the presence and clinical impact of POTS in long COVID patients.2 Highly symptomatic nonhospitalized long COVID patients were included in the analysis, with highly symptomatic defined as sick leave of 50% or greater.
Among this population, differences in demographics and clinical outcomes were compared between those with vs without POTS at a median 12 months following acute COVID-19 infection. Examinations included a 48-hour electrocardiogram, head-up tilt test, and Active Stand Test conducted by a cardiologist.2
There were 467 long COVID patients included in the final analysis, 31% of whom were diagnosed with POTS, 27% did not fulfill POTS criteria, and 42% did not present with clinical signs of POTS. Mean ages in these groups were 40, 44, and 47 years, respectively.2
POTS outcomes
A significant reduction in physical activity was reported in patients with POTS. This group also had an increased heart rate during the 6-minute walk test, both while walking and at rest after the walk.2