A lack of data tracking Canadians who have had COVID-19 could hamper efforts to understand potential post-infection conditions like diabetes and brain fog, experts have warned.
They say the impact of the pandemic on Canada’s healthcare systems and society could last for years, but preparing for it is challenged by the data gap.
dr Kashif Pirzada, an emergency room physician at Toronto’s Humber River Hospital, said reliance on rapid at-home tests for COVID-19 is a major hurdle in data collection.
“They are not tracked centrally and there are very few resources available to these patients,” he said, although COVID-19 appeared to cause diabetes, brain fog or other conditions “very often.”
“If five or 10 percent of our population becomes disabled, which are some of the rates we’re looking at, that’s going to be a big problem for our workforce and for overall health,” said Pirzada, who is also an associate professor at McMaster University.
dr Akshay Jain, an endocrinologist in Surrey, BC, said Canada “will potentially see an avalanche of diabetes cases due to the COVID pandemic.”
But Jain said that, as far as he knows, Health Canada is not collecting data on the aftermath of COVID-19.
People with mild symptoms often failed to contact their doctors, making the data worse, said Jain, who also highlighted reliance on home testing as a problem.
“I just think the health care system as well as the public needs to be aware of both the immediate short-term and long-term effects of COVID,” Jain said.
“You know, the effects of the pandemic will keep us busy for many years to come. I think we need to be aware of that and look out for conditions like diabetes and the complications that come with it.”
When asked if and how it tracks post-COVID-19 conditions and people who have had the disease, Health Canada provided a series of links to information about vaccinations and a daily update of new cases.
“Health systems are the responsibility of each province and territory,” it said.
Jain said studies in the United States and Germany show that the risk of developing diabetes is about 46 percent higher for those who have had COVID-19 than for those who have not been infected.
It’s not clear why people with COVID-19 develop diabetes, Jain said.
One theory is that COVID-19 is causing an “inflammation tsunami” that increases insulin resistance, he said, while another is that steroids used to treat severe COVID-19 could lead to diabetes.
About nine percent of Canadian adults have been diagnosed with diabetes, Jain said. But prediabetes and undiagnosed diabetes push the number down to nearly 30 percent, he said.
“This is already a very high number, and then if you add COVID, those numbers are likely to go even higher.”
In October 2020, Madhu Rao from Toronto tested positive for COVID-19. Eighteen months later, he said he still felt “breathless at times.”
Rao said he’s worried it has something to do with his heart because he’s read that COVID-19 causes heart problems.
An investigation instead revealed that he was a “borderline diabetic” with high blood sugar levels, Rao said.
He said he had no problems with his blood sugar before contracting COVID-19 and described himself as otherwise healthy and active with a weight within the normal range.
His doctor told him she treated many patients with high blood sugar levels and some who developed diabetes after COVID-19, and put him on a strict diet, he said.
“She told me all I can do is delay the start any further.”
A November 2020 study in the journal Diabetes, Obesity and Metabolism states that 14.4 percent of COVID-19 patients have been diagnosed with diabetes.
“Recent reports have shown that newly diagnosed diabetes may carry a greater risk of poor prognosis for COVID-19 than no diabetes or pre-existing diabetes,” it said.
“Hence, COVID-19 patients with newly diagnosed diabetes should be treated early and appropriately, and closely monitored for the onset of full-blown diabetes and other cardiometabolic disorders over the long term.”
Jain said he agrees and “anyone with mild COVID” should speak to a doctor about getting screened for diabetes.
Another condition commonly associated with COVID-19 is the feeling of confusion known as brain fog. A March analysis of several studies on the subject in the Journal of the Neurological Sciences found that up to 32 percent of patients reported brain fog about three months after contracting COVID-19.
Prof Teresa Liu-Ambrose, Canada Research Chair at the University of British Columbia’s Djavad Mowafaghian Center for Brain Health, said there was not enough data to know how many Canadians were affected by the disease, how permanent it was and what the symptoms and consequences are.
Liu-Ambrose said the Canadian Longitudinal Study on Aging, a long-term nationwide research project, is mapping subjects’ brains and assessing their cognition over the next three years to identify differences between people with COVID-19 and those without COVID-19.
However, she said memory fog is largely a subjective complaint, so it might be difficult to quantify.
dr Jurgen Maslany, from Saskatchewan, tested positive for COVID-19 in March and then went back to work about two weeks after he thought he had made a full recovery.
But after tending to one patient, he couldn’t remember the details of what they discussed and realized “something was wrong.”
“And so I immediately took myself off work because it wasn’t safe,” Maslany said.
There was also a feeling of fear, although he wasn’t sure if that was a symptom of brain fog or if he was worried about it.
“It felt like something was kind of chemically shut off in my head,” he said.
It took about three weeks for the symptoms to plateau and now he feels normal again, he said.
But Liu-Ambrose said no one knows what will happen if the brain fog is left untreated.
“Any long-term impact of COVID-19 on the brain and our cognition can be significant,” Liu-Ambrose said.
“These changes could potentially be related to or predict a future decline or risk of dementia. We don’t know – but there certainly is a possibility if these subjective complaints reflect actual changes in the brain.
“It’s an emerging area that needs to be addressed and studied on a larger scale.”
Even a low risk of post-COVID illness could add up to a significant healthcare burden given a high number of COVID cases.
Jain, the diabetes expert, said American data showed an additional 18 cases of diabetes per 1,000 people if they had COVID-19.
This could put “thousands more Canadians at risk of developing type 2 diabetes,” he said, necessitating closer monitoring for diabetic complications like heart attack, stroke, kidney damage and vision loss.
“When we look at the bigger picture together, we see a tremendous strain on Canada’s healthcare system that we haven’t yet acknowledged but is just waiting to happen.”
As for ex-COVID-19 sufferers, Rao said it’s probably a good idea to pay attention to every single symptom after they get the disease.
“Had I just ignored it as physical fatigue or something, I wouldn’t have noticed my blood sugar levels rising.”
Maslany, speaking both as a doctor and as a person experiencing the ongoing aftermath of COVID-19, said it was “vitally important to keep an eye on the complications of this disease.”
“I’m not confident that we’ll be able to find specific therapeutic options, especially in the short term, but I think it’s important to collect the data,” he said.
“First of all, you can’t analyze and fix a problem if you don’t have all the right data.”
This report from The Canadian Press was first published on June 4, 2022.