Neurologic symptoms of long COVID are vast, common, hard to treat, disabling, and can mimic dozens of other syndromes, with some symptoms as serious as those seen in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and postural orthostatic tachycardia syndrome (POTS).
Now, recent evidence has suggested long COVID is primarily an autonomic nervous system disorder.
Their lives may never be the same.
Lindsay S. McAlpine, MD, a specialist in the neurologic sequelae of COVID-19 at the Yale School of Medicine and director of the Yale NeuroCOVID Clinic, New Haven, Connecticut, treats patients who struggle with neurologic symptoms even after disease recovery.
“Some people have the brain fog and the shortness of breath; some have the palpitations and the headaches ... it’s kind of a mix and match,” she said.
Dr. McAlpine’s research has been slowly building up into what could bring about a significant breakthrough in treating some of the most misunderstood and difficult-to-treat symptoms of long COVID.
The Effect of Vascular Inflammation on Long COVID
The National Institute of Neurological Disorders and Stroke recently awarded her a 5-year K23 grant to support her ongoing study, “Magnetic Resonance Imaging Biomarkers of Post-COVID-19 Cerebral Microvascular Dysfunction.”
Using advanced MRI techniques to identify microvascular dysfunction biomarkers in the brain, McAlpine hopes to unearth and better understand the pathophysiology behind neurologic issues post-COVID.
Dr. McAlpine said, “What we’re seeing is that there’s a unique signature of vascular inflammation in long COVID that is distinct from acute COVID. And it has to do with endothelial apathy and platelet dysfunction.”
She’s also looking into whether microvascular dysfunction could increase one’s risk for small vessel disease. Her research is quantitatively building an overall pathophysiology piece by piece.
“We’re quantifying cognitive dysfunction and using objective testing ... a very rigorous 3-hour protocol to really identify the patterns of weakness until we find deficits in memory working and declarative memory, deficits in executive functioning, and others. Those are the three pieces that I’m trying to piece together: The MRI, the blood work, and the cognitive testing,” she said.
Ultimately, Dr. McAlpine believes long COVID will eventually be classified as a peripheral autonomic disorder. The damage being wrought to the whole body also damages the brain’s vasculature, and Dr. McAlpine’s MRI techniques probe at this connection.
“Some of my MRI techniques are dependent on the very subtle changes in blood flow to different regions in response to demand. Brain fog has been a key symptom of POTS and ME/CFS. And it’s now a key symptom of long COVID ... what I’m looking at in some of my studies is how and in which parts of the brain are affected by this,” she said.
Dr. McAlpine’s interest in COVID’s effect on our nervous system goes back all the way to the first wave of patients with COVID, where she noticed an unusually high incidence of ischemic stroke.
“We recognized that COVID really has a huge impact on the vessels ... there’s quite a bit of vascular inflammation. In terms of neurology, we were seeing quite a bit of ischemic stroke, which is unusual,” she said.
Patients don’t normally present with stroke while infected with a virus. Seeking answers, she conducted a stroke study in patients with acute COVID and found profound endotheliopathy — damage to key cells in the lining of blood vessels — leading to a cascade of dysfunction and clotting.