There was once a wise and kind king called Vagus who ruled over the land of Autonomia. His was a peaceful kingdom, until it was suddenly invaded by a fearsome enemy whose forces ravaged the land, killing many and leaving others weak and helpless. The evil enemy, Covidus, would withdraw for a time and invade with renewed force. The helpless King Vagus was left injured and bereft of control.
The vagus nerve is the best-known member of the autonomic nervous system. It's a big nerve connecting the brain to the heart and other internal organs. An ongoing study from Spain analyzing 22 test subjects with vagus nerve dysfunction (VND) suggests damage to the vagus nerve could be an important driver of some of the most distressing features of long COVID.
If I understand the report properly, the investigators used standard ultrasound measurements of the vagus nerve in the neck and the thorax. Since different people can have contrasting perspectives of what they see on an ultrasound scan, different observers often read scans independently without knowing which subject is which (this is known as “blinding”).
Authors of the study said, "In this pilot evaluation, most long COVID subjects with vagus nerve dysfunction symptoms had a range of significant, clinically-relevant, structural and/or functional alterations in their vagus nerve, including nerve thickening, trouble swallowing, and symptoms of impaired breathing. Our findings thus point at vagus nerve dysfunction as a central pathophysiological feature of long COVID."
We should be able to discover rapidly if Vagus is a king in the land of long COVID, a bit player, or just a bystander. That would be firm knowledge and something to build on.
Richard is a retired family doctor who lives in the UK. Until 2020 he was Professor of the Shared Understanding of Medicine at the University of Birmingham UK. For 20 years he produced weekly summaries of research articles from the main medical journals. Here we are giving you his personal comments on Long Covid research as it appears in the medical press. They are meant as pointers rather than complete summaries. Readers wanting more detail are advised to use the links provided to the original article. Richard welcomes feedback from readers but regrets that he cannot provide medical advice.