#17,262
Although the possibility that some COVID patients might develop prolonged, and even permanent, health conditions following infection and `recovery' was broached very early in the pandemic (see here, here, and here), what was once a trickle of studies and reports on `Long COVID' has become a steady stream.
While I don't blog every study that comes out, over the past 10 days alone we've looked at:
EID Journal: Postacute Sequelae of SARS-CoV-2 in University Setting
Neuron: Virus Exposure and Neurodegenerative Disease Risk Across National Biobanks
JAMA: Persistent COVID-19 Symptoms at 6 Months After Onset and the Role of Vaccination Before or After SARS-CoV-2 Infection
I admittedly could have blogged any of a half dozen more that have been published since the first of the year. The question is no longer whether `Long COVID' exists, it is simply how big of an impact is it going to have going forward.
While we've seen a number of studies on the pulmonary, neurological and cardiovascular impacts of COVID infection, we haven't seen much published on its impact on autoimmune diseases like Hashimoto thyroiditis, rheumatoid arthritis, or Sjögren syndrome.
That is, until today, where we look at the preprint of a very large German matched cohort study that finds a strong association between past COVID infection and the development of a wide variety of autoimmune conditions.
The irony is that a lot of people have avoided the COVID vaccines over (unproven) fears it might adversely affect their immune systems, while here we have pretty strong evidence that `natural infection' may be linked to that very outcome.
I've only reproduced the Abstract, and the Conclusion from the full report, so you'll want to follow the link to read it in its entirety.
Incident autoimmune diseases in association with a SARS-CoV-2 infection: A matched cohort studyFalko Tesch, Franz Ehm, Annika Vivirito,Danny Wende, Manuel Batram, Friedrich Loser, Simone Menzer, Josephine Jacob, Martin Roessler, Martin Seifert, Barbara Kind, Christina König, Claudia Schulte, Tilo Buschmann, Dagmar Hertle, Pedro Ballesteros, Stefan Baßler, Barbara Bertele, Thomas Bitterer, Cordula Riederer, Franziska Sobik, Lukas Reitzle, Christa Scheidt-Nave, Jochen Schmittdoi: https://doi.org/10.1101/2023.01.25.23285014
Abstract
Objectives
To investigate whether the risk of developing an incident autoimmune disease is increased in patients with previous COVID-19 disease compared to people without COVID-19.
MethodA cohort was selected from German routine health care data covering 38.9 million individuals. Based on documented diagnoses, we identified individuals with polymerase chain reaction (PCR)-confirmed COVID-19 through December 31, 2020. Patients were matched 1:3 to control patients without COVID-19. Both groups were followed up until June 30, 2021. We used the four quarters preceding the index date until the end of follow-up to analyze the onset of autoimmune diseases during the post-acute period. Incidence rates (IR) per 1000 person-years were calculated for each outcome and patient group. Poisson models were deployed to estimate the incidence rate ratios (IRRs) of developing an autoimmune disease conditional on a preceding diagnosis of COVID-19.
Results
In total, 641,704 patients with COVID-19 were included. Comparing the incidence rates in the COVID-19 (IR=15.05, 95% CI: 14.69-15.42) and matched control groups (IR=10.55, 95% CI: 10.25-10.86), we found a 42.63% higher likelihood of acquiring autoimmunity for patients who had suffered from COVID-19. This estimate was similar for common autoimmune diseases, such as Hashimoto thyroiditis, rheumatoid arthritis, or Sjögren syndrome. The highest IRR was observed for autoimmune disease of the vasculitis group. Patients with a more severe course of COVID-19 were at a greater risk for incident autoimmune diseases.
ConclusionsSARS-CoV-2 infection is associated with an increased risk of developing new-onset autoimmune diseases after the acute phase of infection.
(SNIP)
Conclusion
In this large matched cohort study, COVID-19 was associated with an increased risk of being newly diagnosed with autoimmune disease 3-15 months after SARS-CoV-2 infection. The strength of the association with SARS-CoV-2 infection was most pronounced for autoimmune diseases in the vasculitis group. A more severe course of COVID-19 was associated with a higher likelihood of being newly diagnosed with autoimmune disease. Incident autoimmune diseases were significantly more common in the post-COVID-19 period in all age and sex groups.
The autoimmunity hypothesis is supported by a body of evidence linking viral infections to the pathogenesis of autoimmune diseases as well as results from recent clinical and basic research demonstrating persisting autoantibodies and serological autoreactivity following SARS-CoV-2 infection in a subset of patients. Further epidemiologic, clinical and basic science research is warranted to determine whether SARS-CoV-2 infection triggers the onset of autoimmune disease, to identify the underlying mechanisms and persons at risk, and to investigate effective means of prevention or early treatment
