When Craig Spanza continued to suffer headaches after contracting COVID-19 in March, he thought he may be experiencing some long COVID symptoms. The Vancouver resident expected to be told by his doctor on how to cope with his constant head pain, but instead he was diagnosed as diabetic.
“It was like a little over two weeks after COVID-19 was officially over, when I found out I was diabetic,” said Spanza.
As new variants of concern emerge, there is growing certainty among medical experts that the virus could be causing diabetes, too. Two studies supported by the National Institute of Health (NIH) in the United States found that COVID-19 was causing serious damage to the beta cells in the pancreas, limiting how much insulin could be created. If there is an insufficiency of insulin, blood glucose levels will spike resulting in diabetes.
“The virus can directly damage the cells that produce insulin, which is the master key to control glucose, so less insulin, less glucose control,” said Dr. Remi Rabasa, an endocrinologist at the University of Montreal.
There are at least two other ways the virus could be causing damage inside the human body which could lead to diabetes. If infected by COVID-19, the virus can replicate in the pancreas and into other cells which surround the beta cells. The virus can also cause cells to malfunction so that they’re no longer able to properly regulate blood.
Forty-nine-year-old Spanza admitted he did have some markers for pre-diabetes, but said his bout with COVID-19 was dreadful. It resulted in him being hospitalized as he suffered from difficulties breathing, severe chest pains and a loss of sensation in his extremities.
What Spanza was describing is a severe infection, which Rabasa said “can limit the ability of insulin to act in the tissues,” and is just one of “multiple ways by which COVID-19 could trigger diabetes.”
A Sept. 15 study published on cell.com found that rising blood sugar levels were common among hospitalized COVID-19 patients. Patients required longer hospital stays and had a higher risk of “developing acute respiratory distress syndrome and increased mortality.”
Researchers of the study concluded that hyperglycemia, a spike in blood sugar levels, was being caused by COVID-19 disrupting fat cells’ production of adiponectin, a hormone that helps regulate blood sugar levels.
Rabasa, who also works at the Centre hospitalier de l’Université de Montréal said that he’s been seeing more patients who are dealing with bad cases of COVID-19 display hyperglycemia. He noted that there is “evidence that short term COVID is leading to diabetes.”
He added that we could simply be seeing high blood sugar for a short period of time, which means that while some people may not develop diabetes right away, the effects on their beta cells and tissue damage could be lingering and make them more susceptible to getting it later on.
Research at Harvard Medical School found that of 551 patients hospitalized for COVID-19 in Italy, nearly half became hyperglycemic. Patients were tracked for six months following the initial infection and researchers found that hyperglycemia remained in about 35 per cent of people.
Experts say the concern is not just that patients are contracting diabetes from COVID, but that anyone who is already diabetic that gets COVID is at a higher risk. A Scottish study found that people who already had Type 1 or Type 2 diabetes were already at greater risk of a worse outcome if they contracted COVID-19.
“Overall risks of fatal or critical care unit-treated COVID-19 were substantially elevated in those with Type 1 and Type 2 diabetes compared with the background population,” reads the study.
While infection could be one of the concerns resulting in diabetes, Rabasa said that COVID-19 also has indirect effects on how someone could become diabetic. He mentioned that the “lack of exercise and sedentary lifestyles,” that have resulted from the pandemic where more people are restricted to being at home, could also contribute to it.
“If you’ve been less active, are eating not as good as you’re supposed to, COVID is causing you stress to eat your emotions, those things drive Type 2 diabetes,” he said.
What does the data tell us?
It’s been 100 years since the discovery of insulin, a medical advancement that has allowed people with diabetes to regulate their blood sugar levels at all times. Despite the leaps in medicine and understanding that exercise and good nutrition can help stave off diabetes, there has been a “trend of more people coming forward with newly diagnosed diabetes,” according to Dr. Seema Nagpal, vice president of science and policy at Diabetes Canada.
“It’s a concern that we already see very high rates of diabetes and that this might be another contributing factor,” she said.
A 2020 analysis by McMaster University found that of patients with severe COVID-19, nearly 15 per cent developed diabetes. The authors of the study noted some people could already have been at-risk of diabetes before contracting the virus.
Nagpal noted that there hasn’t been data collected in Canada regarding the current rate of diabetes since the pandemic began. As a result, she said Diabetes Canada can’t confirm if the potential spike in diabetes rates is directly caused by COVID-19.
A New York-based study that looked at patients hospitalized at New York-Presbyterian Hospital/Weill Cornell Medical Center and affiliated campuses at Queens and Lower Manhattan Hospital found that 49.7 per cent of the 3,864 patients diagnosed between March 1, 2020 and May 15, 2020, had hyperglycemia.
While nearly half of the patients suffering from hyperglycemia is staggering, the numbers rose to “91.1% and 72.8% among intubated and deceased patients,” researchers found. The hospital stay for people with hyperglycemia was 10 days compared to five days for those without.
The authors of an August 2021 study by Stanford University definitively concluded that “SARS-CoV-2 can directly induce beta cell killing,” which would support the growing evidence that COVID-19 has direct ties to diabetes.
How to combat diabetes?
Outside vaccines and masks being ways to limit COVID-19 infections and therefore potential cases of diabetes, there are ways to mitigate risk. Diabetes Canada notes making lifestyle changes helps reduce your chance of developing diabetes.
“Eating healthy, moving more, and losing weight if you are overweight are the most effective things you can do to reduce your risk of developing Type 2 diabetes,” they write on their website.
Spanza is grateful for early diagnosis in his path to recovery, saying he’s been able to incorporate better nutrition and exercise in his diet to keep his diabetes in check. He said he watches how much carbohydrates, fat and sugar he eats and is overall a lot more aware of his dietary choices.
Since he implemented the changes, Spanza said the headaches are not as frequent and he feels physically much better.
“It feels like it’s suddenly – from the middle of October – it feels like it suddenly has been dropping off,” he said.
— with files from Jamie Maraucher and Leslie Whyte