This is a summary, written by members of the CITF Secretariat, of:
Son K, Jamil R, Chowdhury A, Mukherjee M, Venegas C, Miyasaki K, Zhang K, Patel Z, Salter B, Yuen ACY, Soon K, -Lau K, Cowbrough B, Radford K, Huang C, Kjarsgaard M, Dvorkin-Gheva A, Smith J, Li QZ, Waserman S, Ryerson CJ, Nair P, Ho T, Balakrishnan N, Nazy I, Bowdish DME, Svenningsen S, Carlsten C, Mukherjee M. Circulating Antinuclear Autoantibodies in COVID-19 Survivors Predict Long-COVID Symptoms. European Respiratory Journal, 2022, 2200970; DOI: 10.1183/13993003.00970-2022.
The results and/or conclusions contained in the research do not necessarily reflect the views of all CITF members.
A study funded by the CITF and the Canadian Institutes of Health Research and led by Dr. Manali Mukherjee (McMaster University) has found two things: that in most people with persistent COVID symptoms, long COVID does not last forever and a possible link between long COVID and autoimmune disease. The results are published in the European Respiratory Journal.
- Although 75% of COVID-19 infected individuals recovered at the 12-month mark after becoming ill with the virus, 25% still had at least one of the three most common symptoms: coughing, fatigue, and breathlessness.
- Patients with persistent symptoms had antibodies associated with autoimmune illnesses, as well as raised levels of cytokines, which cause inflammation.
- Nearly 80% of the COVID-19 patients had two or more of these antibodies in their blood six months after the infection. This fell to 41% after a year.
- In patients who recovered, a reduction in autoantibodies and cytokines was matched by their symptoms improving. Those who had elevated antibody and cytokine levels after one year were those whose symptoms persisted.
- COVID-19 patients who had more severe disease developed a stronger autoimmune response evident three months after recovering from COVID-19. Most of the healthy volunteers had no sign of these antibodies in their blood. In those who had experienced a non-COVID respiratory infection, levels of these antibodies were also comparatively low.
- For most patients in the study, even if they had autoantibodies soon after their infection, this resolved after 12 months. However, in some patients, autoantibodies persist, and these patients may require clinical assistance.
Consenting adults, with a positive PCR test for SARS-CoV-2 and no previous diagnosis of autoimmune disease were recruited via community self-referrals, physician referrals, and hospital in/out-patient post-discharge follow-ups between August 2020 and September 2021 from St. Joseph’s Healthcare Hamilton, Vancouver General Hospital, and St. Paul’s Hospital in Vancouver. Of the 106 participants, 26 recovered from COVID-19 at home, 35 were admitted to the ICU, and 45 were hospitalized but not ICU-admitted.
COVID-19 patients were compared to other adults with respiratory infections who had respiratory symptoms consistent with COVID-19 but who were not seropositive 1-3 months post-recovery of their infection and/or symptoms.
Dr. Mukherjee suggests patients with persistent long COVID symptoms should see a rheumatologist, instead of or in addition to a respirologist or infectious disease specialist, as the former specialize in autoimmune disorders and can better assess the development of rheumatological complications and the need for an early intervention.