Neurological effects post-COVID and what history tells us about post-viral syndromes.
Results from a large retrospective study of nearly 240,000 subjects recently published in The Lancet show that in the six months after becoming ill with COVID, approximately one-third of the surviving patients were diagnosed with at least one neurological or psychological condition.1
Patients who continue to exhibit lingering symptoms or develop other disorders long after recovery from the initial virus have been designated “long-haulers.”
Some of the Lancet study highlights included:
The problem with retrospective studies.
A retrospective study uses existing data that have been recorded for reasons other than research. A retrospective case series is the description of a group of cases with a new or unusual disease or treatment. And as the investigators discussed, “a study of this kind can only show associations; efforts to identify mechanisms and assess causality will require prospective cohort studies and additional study designs.”
Also, in these cases we are relying on a positive COVID test in the majority of patients as the confirmatory evidence of COVID. Which is unique in that this is the first time in my 30 years of medical practice that mass diagnoses have been made from only a test, but in many cases without a patient examination.
Perhaps the biggest problem with this study is that we were not given ANY other variables that could be involved in these outcomes. While the virus may reveal or accelerate the presentation of certain underlying psychiatric and neurologic conditions, it is rarely just one thing that causes disease of the brain or body. Patients may have underlying issues as yet identified and the virus essentially stresses the system so problems quickly manifest as a result.
We know and I have written about this over the course of the last year that there also has been massive psychiatric sequelae from the last year of quarantine, economic hardships, wearing masks and social isolation, and a great deal of fear. So it’s difficult to say then how much the brains of some individuals may have been predisposed to developing neurological issues in the event of a COVID infection.
Are post-viral syndromes new?
The short answer is no. Post-viral syndromes have occurred throughout history. For example, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disabling and complex illness. First popularized as a diagnosis in the 1980s, but actually in existence since before the 20th century, ME/CFS is thought to result from a misguided immune response to a viral and or other pathogen. A growing number of inflammatory disease states, including neurological conditions and cancers, are tied to dysbiosis or imbalance of these human microbiome communities. Gut microbiome dysbiosis has been identified in ME/CFS is characterized by neuroinflammation, severe fatigue, excessive post-exertional exhaustion, disturbed sleep, flu-like episodes, cognitive problems, sensory hypersensitivity, muscle and joint pain, headache, bowel symptoms, and severe impairment of daily functioning. A 2018 study in the journal Frontiers in Pediatrics details the theory is that a virus overloads the immune system, causing a reaction that triggers symptoms.2
The authors of a study in 2015 suggest that the symptom of fatigue after a viral infection is due to inflammation in the brain. Viral infections such as influenza cause the occurrence of acute inflammation, and pro-inflammatory cytokines including interleukin (IL)-1β and/or antiviral cytokines including interferons (IFNs) are produced by activation of Toll-like receptors (TLRs) in the periphery.3 Viruses cause the immune system to respond and attack them. This response causes stress and inflammation in the body. The effects of this response often leave people feeling down, fatigued, and sometimes depressed.
Other historic examples of post-pandemic issues.
One of the few researchers to investigate the link between long term impacts to health was historical demographer Svenn-Erik Mamelund, PhD whose focus was on the impacts of the Spanish influenza (“flu”) event. Mamelund looked at asylum hospitalizations in Norway from 1872 to 1929 and found that the number of first-time hospitalized patients with mental disorders attributed to the Spanish flu increased by an average annual factor of 7.2 in the six years following the pandemic. In addition, he pointed out that survivors reported sleep disturbances, depression, mental distraction, dizziness, and difficulties coping at work, and that death rates in the United States from the flu during the years 1918-1920 were significantly and positively related to suicide.4
We know too that pandemic influenza A (H1N1) infection was associated with a more than two-fold increased risk of CFS/ME. Acute manifestations of swine flu varied from behavioral changes, fear of misdiagnosis during outbreak, neurological features like seizures, encephalopathy, encephalitis, transverse myelitis, aseptic meningitis, multiple sclerosis, and Guillian-Barre Syndrome.2
The rising tide of disease.
Even before COVID 19 came into our lives, we have to acknowledge that much of our world was already seeing enormous problems related to their health.
54% of children now have a chronic disease.
60% of adults have one and 40% have two chronic diseases.
1 in 5 Americans will develop an autoimmune disease.
1 in 33 children are born with autism; estimated projections are one in two in the next 15 years.
50 million individuals suffer with neuropsychiatric problems.
Every day 43 children age 19 and under are diagnosed with cancer in the U.S.
100 million people are living with unremitting chronic pain.
Without question, COVID 19 is a very serious virus. But we can’t talk about the state of our health – or lack thereof – without also considering what else may be going on that brings down the brain and our body. It is not just one thing, and that includes any virus, which is solely responsible. We’ve seen just how many disorders have a multifactorial etiology. And how many of the risks may in fact be modifiable lifestyle factors too.
It’s crucial to truly explore all facets of this virus as we would with any other condition. There is no single answer to a complex medical problem. We can’t expect a vaccine, for example, to address what is likely a host of underlying issues – just as we can’t expect a single vitamin or pill to make up for a poor diet, lack of exercise, exposure to toxins or abuse of alcohol. This, in and of itself, is already an epidemic and a crisis we must explore if we are to identify the path to good health for the wellbeing of more patients. And the future of our planet.
In hope and healing,
Dr. Suzanne Gazda
1 Taquet, M., Geddes, J.R., Husain, M., Luciano, S., Harrison, P.J. 6-month neurological and psychiatric outcomes in 236 379 survivors of COVID-19: a retrospective cohort study using electronic health records. The Lancet Psychiatry (2021)
2 Proal A, Marshall T. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in the Era of the Human Microbiome: Persistent Pathogens Drive Chronic Symptoms by Interfering With Host Metabolism, Gene Expression, and Immunity. Front Pediatr. 2018;6:373. Published 2018 Dec 4. doi:10.3389/fped.2018.00373
3 Yamato M, Kataoka Y. Fatigue sensation following peripheral viral infection is triggered by neuroinflammation: who will answer these questions?. Neural Regen Res. 2015;10(2):203-204. doi:10.4103/1673-5374.152369
4 Eghihian, G. The Spanish Flu Pandemic and Mental Health: A Historical Perspective. (2020) Psychiatric Times. https://www.psychiatrictimes.com/view/spanish-flu-pandemic-and-mental-health-historical-perspective
Additional reading from our Blog Archives:
Dr. Suzanne Gazada, Integrative Neurology