"Our study finds that 67% of individuals with Long COVID are developing dysautonomia. That’s an estimated 38 million Americans with Long COVID dysautonomia, and millions more around the world,” says Lauren Stiles, President of Dysautonomia International and Research Assistant Professor of Neurology at Stony Brook University.
"We need the National Institutes of Health to immediately address this crisis and begin funding research aimed at developing effective treatments for Long COVID dysautonomia,” says Jacqueline Rutter, a Dysautonomia International Board Member whose family has been impacted by Long COVID.
I haven’t seen a lot of data looking specifically at the impact on people who already had some sort of dysautonomia - everything’s super new still so most studies are pretty broad. But given that the research seems to suggest COVID attacks the nervous system and that damage causes new cases, I would guess the damage could also just as easily worsen existing cases.