There may be a double whammy when it comes to the covid-19 pandemic and diabetes. Scientists are warning that people with preexisting diabetes have a higher risk of developing serious complications from the viral illness, while the infection may also raise people’s risk of developing a new case of diabetes. But it’s not completely certain why this relationship between the two conditions exists.
It was apparent early on that chronic health problems like type 1 and type 2 diabetes can increase the risk of a life-threatening infection from the coronavirus that causes covid-19. One study from the UK has suggested that having either type of diabetes may increase the chance of death by two- to threefold, while also finding that around 30 percent of people who died of covid-19 had type 2 diabetes at the time.
But there’s also been growing evidence that this link goes both ways—that having the virus raises a person’s risk of developing new-onset diabetes. In some cases, covid-19 patients have rapidly developed diabetic ketoacidosis, a severe complication where blood sugar spikes dramatically and can cause coma if not immediately treated with high doses of insulin.
Diabetes is simply defined by the lack of bodily control over your blood sugar. This can happen a few different ways, but it’s often connected to the hormone insulin, which regulates blood sugar. People with type 1 diabetes are unable to produce insulin, usually from an early age. People with type 2 diabetes, usually developed in adulthood, either lose the ability to produce insulin or their bodies stop responding to it as normal. There are also other forms of diabetes that can happen temporarily, such as gestational diabetes during pregnancy.
It’s a complicated disorder, caused by a combination of genetic and environmental factors, including stress. But scientists are suspecting that covid-19 infection may bring its own unique influence to the table. This weekend, a group of experts in diabetes research signed a letter published in the New England Journal of Medicine, putting forth the theory that the virus can have a “diabetogenic effect” that goes beyond the stress put on the body from any severe infection.
It’s well established that the virus infects our body’s cells by binding to their angiotensin-converting enzyme 2 (ACE2) receptors. These receptors are readily found in the cells of the throat, where the virus often makes its home. But they’re also found in the cells that make up our pancreas and other key organs that regulate insulin and our metabolism. So it’s plausible, the authors write, that infection could somehow affect the body’s blood sugar-related functions, while those same functions, if already damaged from diabetes, could make the infection more harmful.
The authors also cite research showing that some people who caught the original SARS virus (a close relative of the coronavirus behind covid-19) over 15 years ago also developed acute cases of diabetes.
Right now, though, there’s still a lot of unknowns, the authors caution.
“Whether the alterations of glucose metabolism that occur with a sudden onset in severe covid-19 persist or remit when the infection resolves is unclear,” they wrote.
Even if these diabetic symptoms aren’t long-lasting, there’s still the chance that they could raise someone’s risk of developing type 2 diabetes later on in life, much as gestational diabetes does. On the flip side, there’s the worry that the long-term metabolism of people with preexisting diabetes who survive their infection may end up in even rougher shape as a result. Other questions include whether coronavirus-related diabetes biologically looks more like type 1 or type 2 diabetes or if it could represent another never-before-seen type.
To hopefully answer these questions someday, the authors announced the creation of a patient registry to track the extent of diabetes cases potentially related to covid-19, as well as to better study how preexisting diabetes affects patients and vice-versa.
Whatever these doctors end up finding, it’s yet another reminder that it’ll take years to truly understand the full range of harm that covid-19 causes.