COVID-19 “long-hauler” has worked itself into our vernacular, but a Canadian study is looking into exactly what that means.
The goal of the COVID-19 Prospective Cohort Study, the first Canadian study to look at one-year outcomes in patients and their caregivers, is to raise the standard of care for patients who have had COVID-19 and to provide clinical pathways and guidelines that may help clinicians and policymakers make better decisions.
Angela Cheung and Margaret Herridge are co-leads of the study that aims to “try to understand what it means to be a long-hauler” – a COVID-19 survivor who is suffering long-term symptoms.
They are treating long-haulers now but Cheung says “it’s a little bit early to know that piece per se.” The only thing the doctors know for sure is what they learned from their previous research on severe acute respiratory syndrome (SARS) and acute respiratory distress syndrome (ARDS).
Cheung is an internal medicine specialist and scientist at University Health Network in Toronto. Herridge is a respiratory and critical-care specialist at University Health Network and a scientist at the Toronto General Research Institute. Their previous research on SARS and ARDS makes them the ideal co-leads of CANCOV.
CANCOV is currently recruiting patients who have tested positive for COVID-19 in British Columbia, Alberta, Ontario and Quebec. The study includes patients who were not sick enough to be admitted to hospital and were told to stay home and isolate; those who were sick enough to be admitted to hospital; and those sick enough to be admitted to an intensive care unit (ICU) and required mechanical ventilation. There are multiple centres in each of the provinces providing clinical and research follow-up for these patients.
The researchers aim to follow 2,000 COVID-positive patients and 500 caregivers. To date, 390 people are enrolled in Ontario. That includes 378 COVID-positive patients and 12 caregivers, usually family members but sometimes close friends. Of the patients, 103 were not hospitalized; 55 were hospitalized but did not require admission to the ICU; and 65 required ICU care. Another 155 participants have enrolled in antibody testing.
Caregivers are included to see how they were affected by the experience, as previous research into ARDS showed that people who care for patients also experience anxiety, depression and post-traumatic stress disorder.
Cheung says the program was started in Ontario in March “when we saw that the numbers were going up.” Initially an Ontario effort, the study was funded by the University of Toronto COVID-19 Action Initiative. It has since become a national effort and is now funded by the Canadian Institute of Health Research. According to Cheung, “depending on how the pandemic goes, we plan to add more centres.”
The researchers are working with other post-COVID clinics because “the program needs partnership from patients and other post-COVID clinics to help understand this,” says Cheung.
While CANCOV is running its many research projects, it is also providing clinic care to patients. More than 100 investigators are involved with CANCOV and have both clinical and research expertise – including, but not limited to, in cardiology, neurology, psychiatry, respirology, hematology and dermatology.
Patients are tested and fill out questionnaires at follow-up visits that are tailored to their individual clinical issues. Their exercise capacity is tested and their oxygen saturation monitored. They are given physical exams, including tests of muscle strength, and their cognition is tested.
Blood samples are taken to look at the patient’s genes and see if and how they have been modified by the infection. Antibody testing and immune analysis are also performed. The blood is also analyzed for immune and cytokine profiles. Cytokines are small proteins that allow cells to communicate with each other, including by signalling the cells involved in the immune response.
The researchers are starting to see that “COVID-19 does affect patients differently,” says Cheung. “There are some patients who have a cough and a cold, or a headache, and they get better – back to their baseline … certainly over a couple of weeks and sometimes over months.
“There are those who have had residual symptoms even though they may (no longer) be infectious. They have residual symptoms as long as six months.”
One 35-year-old Canadian woman has been dealing with COVID-19 since March. “Everyone is just told you either recover or you die,” Ashley Antonio told the Washington Post recently. “There’s never talk of all the people that are trapped somewhere in the middle with all of these long-term effects. We’re not recovered. We’re just not COVID-positive anymore.”
Cheung says some patients were so sick that they required mechanical ventilation in an ICU and are now “still very weak and not back to their baseline.”
“There is a whole spectrum,” she says.
They are “seeing people who have symptoms and are trying to understand why they have symptoms.” The researchers are “trying to tease out quite a few things…. How is it different and how is it similar to other viruses.”
Cheung says that their previous research showed that people who recovered from SARS and ARDS “may still be short of breath and weak but, over time … the PFTs (breathing tests) do return to normal, especially if they had no pulmonary disease prior to the illness.”
The study showed that five years after suffering from ARDS, patients still had exercise and psychological issues. The researchers also demonstrated that the decreased physical quality of life and increased costs and use of healthcare services are also important consequences of severe lung injury.
“I think in general we should be careful because we don’t really know who can get really sick and (for) who it may be like a flu. We have to be careful not just for (the) long term but because of that simple fact,” stresses Cheung.
“There are patients who have longer symptoms and this is distressing to them and it’s too early to tell what causes these long-term issues.”
Cheung has a message for people: “The numbers are high and people should take care. We need to pay attention to this. Try not to go out as much and really just do essential things. Try to keep physical distancing, wash hands and wear a mask.”