Many of these patients had no history of diabetes. Some who developed high blood sugar while having Covid-19, the disease caused by the novel coronavirus, returned to normal when they left the hospital. Others went home diagnosed with full blown diabetes. “We’ve definitely seen an increase in patients who were newly diagnosed,” said Zilbermint.
Although Covid-19 frequently attacks the lungs, it is increasingly linked to a range of problems, including blood clots, neurological disorders, and kidney and heart damage. Researchers say that emerging diabetes could soon add to these complications – both type 1, where people cannot produce the insulin needed to regulate their blood sugar, and type 2, where they make too little insulin or against it Become insulin resistant. causing your blood sugar level to rise. However, scientists don’t know whether covid-19 could accelerate or actually cause problems that are already occurring – or both.
In January 2020, doctors in Wuhan, China, found elevated blood sugar in patients with Covid-19. Doctors in Italy, another early hot spot, wondered if diabetes diagnoses might follow, given the long-observed association between viral infections and the incidence of diabetes. This association has been seen in previous outbreaks of other coronavirus diseases such as SARS.
A year into the pandemic, the exact nature and extent of the link between Covid and diabetes remains a mystery. Many of those who develop diabetes during or after Covid-19 have risk factors such as obesity or a family history of the disease. Elevated blood sugar levels are also common in patients taking dexamethasone, a steroid that is a front-line treatment for Covid-19. However, cases have also occurred in patients who are not known to have any risk factors or health concerns. And some cases develop months after the body clears the virus.
John Kunkel, a 47-year-old bank clerk in Evening Shade, Ark., Was one of the surprise cases. In early July he was hospitalized with covid-19. During a follow-up visit to see his doctor, he learned that he had dangerously high blood sugar levels and was resumed. Kunkel has since received a diagnosis of type 2 diabetes.
“I didn’t have any pre-existing health problems,” he said. “I was blown away. Why?”
Kunkel has had five emergency rooms and three hospital stays since he became Covid-19. He recently lost his job because he was unable to return to work due to persistent health problems. “Are you going to get your life back?” he asked. “Nobody knows.”
According to a global analysis published Nov. 27 in the journal Diabetes, Obesity and Metabolism, 14.4 percent of people hospitalized with severe Covid-19 developed diabetes. The international research group examined reports of uncontrolled hyperglycaemia or high blood sugar in more than 3,700 Covid-19 patients in eight studies. While these diagnoses could be the result of a long-observed response to serious illness or to treatment with steroids, the authors wrote, a direct effect of Covid-19 “should also be considered”.
Concerns that Covid-19 could be directly linked were also supported by the exceptionally high doses of insulin that diabetic patients with severe Covid-19 often require and the dangerous complications they develop.
Researchers don’t understand exactly how Covid-19 can trigger type 1 or type 2 diabetes, or whether the cases are temporary or permanent. However, they are looking for answers to these and other questions, including whether the novel coronavirus may have spawned an entirely new type of diabetes that may evolve differently from traditional forms of the disease.
Francesco Rubino, Professor of Diabetes Surgery at King’s College London, believes there is a link between the diseases.
Over the summer, he and a group of other diabetes experts created a global registry of patients with diabetes related to Covid-19. After announcing that with an editorial in the New England Journal of Medicine, more than 350 institutions from around the world responded, he said.
The database is collecting patients – over 150 to date – although it will be months before researchers sifted through the data to draw conclusions. “We really have to dig deeper,” said Rubino. “But it sounds like we have a real problem with Covid and diabetes.”
Some of the cases reported to his database don’t fit the common profile of type 1 diabetes, where the pancreas produces little or no insulin, or type 2 diabetes, where people become insulin resistant, he said. Typically, a patient with one type of diabetes will experience certain complications. For example, people with type 1 can burn their fat stores, or people with type 2 can have a syndrome that can lead to severe dehydration and coma when the body pumps excess blood sugar into the urine. For some patients with Covid-19, however, the complications are cross-cutting.
“There is a good chance the mechanism of diabetes is not typical,” said Rubino. “There could be a hybrid form. It’s about. “
Rubino is particularly concerned about reports of diabetes diagnoses following mild or asymptomatic coronavirus infections. As the number of novel coronavirus infections continues to rise, he said, “You could see a significantly new volume of diabetes diagnoses.”
Diabetes is already increasing at an alarming rate in the United States. It is estimated that 34.2 million people, or 10.5 percent of the population, have the disorder. And roughly one in three Americans, or 88 million people, have prediabetes, which indicates they are on the way to type 2. If not controlled, the disease can damage many parts of the body and is associated with serious complications such as heart disease and stroke, blindness, kidney failure, and nerve damage.
However, whether those with diabetes newly diagnosed after Covid-19 have a lifelong problem is unclear. Following the 2003 SARS pandemic, Chinese researchers tracked 39 patients with no history of diabetes who had developed acute diabetes within days of hospitalization with SARS. With the exception of six, their blood sugar levels had dropped by the time they were discharged and only two had diabetes after two years. The researchers also found evidence that the SARS virus could attack insulin-producing beta cells in the pancreas.
Beta cells play a major role in both types of diabetes: the bodies of people with type 1 attack the cells and destroy them altogether, thereby stopping insulin production. Type 2 diabetics become resistant to the insulin they produce, so the beta cells keep producing more and eventually wear out.
“If scientists could figure out how or if viral infection can damage beta cells, or what role viruses play in the development of the disease, it would be a real turning point,” said Katie Colbert Coate, diabetes researcher and medical educator in medicine at Vanderbilt University Medical Center.
Although people with diabetes are no more susceptible to Covid-19 than people without diabetes, they are at a much higher risk of serious complications or death if they do. In the early days of the pandemic, just over a third of those who died from Covid-19 in UK hospitals had already had cases of diabetes. Doctors in Wuhan also found that people with newly diagnosed diabetes were more likely to need intensive care than people with diabetes before they contracted Covid-19.
New diagnoses of diabetes in people without classic risk factors are also scattered in the case reports: A 37-year-old previously healthy Chinese man who went to hospital with a severe and in some cases fatal complication of diabetes; A 19-year-old German who developed type 1 diabetes five to seven weeks after a novel coronavirus infection, but who lacked the antibodies usually associated with the autoimmune disease.
Doctors at Children’s Hospital in Los Angeles, meanwhile, noted an increase in type 2 diagnoses in children and a serious complication of diabetes. After some of them showed evidence of previous coronavirus infections, Senta Georgia, an investigator at the hospital’s Saban Research Institute, began looking deeper. Her research, which reuses tissues from primates used in vaccine tests, is currently under peer review.
“Only with the scientific public space can we publish all of this data, evaluate its strengths and weaknesses … until we really get the information we need,” Georgia said.
Such reports have also increased the sense of urgency for researchers like Coate, who have stopped other work looking for keys to understanding the mechanism of the disease by studying how Covid-19 could damage beta cells or other structures in the pancreas. She and others ask whether certain covid symptoms predict whether a patient is prone to diabetes and, most importantly, whether the onset of the disease is an effect of the immune response or a result of the virus that attacks insulin-producing cells directly.
ACE2 receptor cells, the entrance of the novel coronavirus into the body, could provide an answer. When the spike proteins surrounding the virus bind to a host cell with an ACE2 receptor, they open a cellular door through which the virus can abduct the cell.
Strong evidence of ACE2 receptors on beta cells could confirm the long-standing suspicion that viruses cause diabetes. However, the research results are inconclusive: since the pancreas breaks down quickly after death, it is difficult to obtain good samples from autopsied people. And every study has its own limits.
Last year, researchers at Cornell University grew human pancreatic cells and managed to infect them with SARS-CoV-2, as the novel coronavirus is technically known. They found ACE2 receptors on the cells, but the cells were grown in a laboratory, not in a human body.
Coate and her colleagues at Vanderbilt University were able to confirm the presence of ACE2 receptors in the physical structures of the pancreas. However, their study focused on patients without Covid-19 and found no evidence of the receptors on the insulin-producing beta cells. An Italian study found the receptors in beta cells, but the donors also did not have Covid-19. Until receptors in pancreatic beta cells in the tissues of Covid-19 patients can be consistently confirmed by other researchers, the search for the mechanism underlying the diabetes-Covid-19 connection will continue. It is also investigating how Covid-19 can damage other parts of the endocrine system that could also play a role in the disease mechanism.
For newly diagnosed patients like nurse Tanisha Flowers, the answers cannot come soon enough.
The 40-year-old was infected in April while working in a Covid-19 ward at a Richmond hospital. He was diagnosed with diabetes in October. She is now taking medication every day, watching her diet, and is all too aware that she may be a diabetic for life.
“I’m not myself anymore,” said Flowers. “Nobody knows what the permanent results are.”