Hornig and other scientists point to autonomic nervous system dysregulation as the possible explanation for long-haulers’ tachycardia, extreme fatigue, and other persistent symptoms. The system controls involuntary physiologic processes such as heart rate, blood pressure, respiration, and digestion.
Stanford University neurologist Mitchell Miglis, MD, who specializes in autonomic nervous system disorders such as postural orthostatic tachycardia syndrome (POTS), recently coauthored a
case report about a previously healthy, 26-year-old emergency department nurse who developed classic POTS symptoms—fatigue, tachycardia—that hadn’t resolved 5.5 months after she was diagnosed with COVID-19 in March.
“One of the most common symptoms of POTS is brain fog,” Miglis noted. “It’s not clearly related to blood flow to the brain. It’s something else.”