What does it mean to be a COVID-19 Long-Hauler?
Some of the serious aspects of COVID-19 are long-term symptoms that persist for a significant period after SARS-CoV-2 infection and acute symptoms have apparently resolved. People experiencing these conditions have been called “long-haulers” and are a consequential proportion of those infected with SARS-CoV-2. Particularly, many patients who recovered not only from the severe disease, COVID-19, but also mild and moderate disease, have experienced long-term consequences. In this context, we discuss the most common persistent symptoms and general causative factors of long-haul COVID-19.
The ranges of symptoms are sufficiently diverse in that their direct underlying causes may differ due to the differences in viral loads and tissue distribution and in the subsequent immune responses. Let’s consider a few factors in detail. Recently, postural orthopedic tachycardia syndrome (POTS) has gained attention (2). POTS may be associated with autoantibodies to adrenergic receptors(3), suggesting that inappropriate immune response to SARS-CoV-2 can cause damage to the autonomic nervous system. POTS is associated with greatly elevated heart rates resulting from small movement or standing creating dizziness and fatigue. It is diagnosed by immobilizing the patient on a tilting table and measuring changes in heart rate between the horizontal and vertical. While not unique to COVID-19, it apparently can be triggered by the infection with SARS-CoV-2. Although it is treatable, recovery process can be lengthy, and the condition may never completely resolve.
There are obviously a greater variety of long-term issues than can be adequately discussed in this type of forum. There are far more questions than there are answers. What are the mechanisms of these conditions? In a practical sense, are some, or all, of these discrete, underlying health conditions (i.e., chronic respiratory illness including asthma, obesity, diabetes or cancer) even though initiated by the same virus? What therapies will be available for prevention or treatment? How long will they persist? Will most of them eventually resolve? They represent a major aspect of COVID-19 that is perhaps not yet widely appreciated. None of this is presently well understood, and it needs to be, as we are, in a sense, in a new world living with, and treating, COVID-19 long-haulers.
- A. Carfi, R. Bernabei, F. Landi, C.-P.-A. C. S. G. Gemelli Against, Persistent Symptoms in Patients After Acute COVID-19. JAMA 324, 603-605 (2020).
- A. Fedorowski, Postural orthostatic tachycardia syndrome: clinical presentation, aetiology and management. J Intern Med 285, 352-366 (2019).
- A. Fedorowski et al., Antiadrenergic autoimmunity in postural tachycardia syndrome. Europace 19, 1211-1219 (2017).
- J. B. Cruz Rodriguez, R. A. Lange, D. Mukherjee, Gamut of cardiac manifestations and complications of COVID-19: a contemporary review. Journal of investigative medicine : the official publication of the American Federation for Clinical Research 68, 1334-1340 (2020).
- J. F. Ludvigsson, Case report and systematic review suggest that children may experience similar long-term effects to adults after clinical COVID-19. Acta Paediatr, (2020).
- A. M. Baig, Deleterious Outcomes in Long-Hauler COVID-19: The Effects of SARS-CoV-2 on the CNS in Chronic COVID Syndrome. ACS Chem Neurosci 11, 4017-4020 (2020).
- M. Panigada et al., Hypercoagulability of COVID-19 patients in intensive care unit: A report of thromboelastography findings and other parameters of hemostasis. J Thromb Haemost 18, 1738-1742 (2020).
- N. Tang, D. Li, X. Wang, Z. Sun, Abnormal coagulation parameters are associated with poor prognosis in patients with novel coronavirus pneumonia. J Thromb Haemost 18, 844-847 (2020).
- S. Abu-Rumeileh, A. Abdelhak, M. Foschi, H. Tumani, M. Otto, Guillain-Barre syndrome spectrum associated with COVID-19: an up-to-date systematic review of 73 cases. J Neurol, (2020).