Diabetes and COVID-19 may have a bidirectional relationship, meaning they may affect each other. People with diabetes, especially unmanaged diabetes, have a higher risk of severe COVID-19. Also, COVID-19 may increase the risk of new or worsening diabetes.

Diabetes can weaken the immune system. People with any type of diabetes may be more vulnerable to severe COVID-19 illness.

People with diabetes make up a large share of those with severe COVID-19. According to the Centers for Disease Control and Prevention (CDC), in the early days of the COVID-19 pandemic, 39.7% of people hospitalized for COVID-19 had diabetes. The figure for those aged 50–64 was higher, at 46.5%.

Treating and attempting to prevent type 2 diabetes may therefore reduce the risk of severe COVID-19 illness. Similarly, reducing the risk of COVID-19 could lower the risk of developing diabetes.

This article will examine the relationship between diabetes and COVID-19 and detail ways to prevent both diseases.

Coronavirus data

All data and statistics are based on publicly available data at the time of publication. Some information may be out of date. Visit our coronavirus hub for the most recent information on COVID-19.

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Overall, people with all forms of diabetes are more likely to have negative COVID-19 outcomes. This is because diabetes may weaken the immune system. It can also cause serious health conditions such as heart disease and kidney disease.

Type 1 diabetes

Type 1 diabetes, which doctors previously referred to as juvenile diabetes, may weaken the immune system. Especially if people do not have proper blood glucose management, type 1 diabetes can increase the risk of negative COVID-19 outcomes such as death and hospitalization.

A CDC report in 2020 stated that the risk of hospitalization was 6 times higher and the risk of death was 12 times higher in people with COVID-19 who had an underlying medical condition such as type 1 diabetes than in those who did not.

Emerging research suggests that COVID-19 may be a risk factor for type 1 diabetes in children. A 2022 population study found that children with a recent history of COVID-19 were more likely to subsequently have a type 1 diabetes diagnosis.

Read more about type 1 diabetes here.

Type 2 diabetes

Type 2 diabetes is the most common form of diabetes. It tends to develop in adulthood, and many people with type 2 diabetes have other health issues, such as high blood pressure and coronary heart disease. These conditions may further increase the risk of hospitalization and death in this population.

Many studies do not distinguish between type 1 and type 2 diabetes. Both can cause high blood sugar, but type 2 diabetes tends to occur along with metabolic syndrome. Researchers are still unsure what role metabolic syndrome, as opposed to hyperglycemia alone, plays in COVID-19.

Pregnancy, diabetes, and COVID-19

Pregnancy increases insulin resistance, which may increase the risk of negative health outcomes in people with COVID-19. According to the CDC, 2–10% of pregnant people develop gestational diabetes. This is a type of pregnancy-induced diabetes that may weaken the immune system.

Like other types of diabetes, gestational diabetes may increase the risk of negative COVID-19 outcomes. According to a 2022 study, pregnant people with gestational diabetes and COVID-19 are 3.3 times more likely to need admission to an intensive care unit than those without gestational diabetes.

Diabetes remission and COVID-19

Diabetes remission can mean a person’s blood glucose has remained below the diabetes range for at least 3 months. People in diabetes remission are less vulnerable to diabetes complications, especially when they experience remission early in the disease course.

This may also decrease the risk of severe COVID-19 outcomes. Research consistently finds that blood sugar management is a major factor, though not the only factor, in predicting negative outcomes in people with diabetes who develop COVID-19.

For example, in a 2021 review, researchers found that 94% of people with COVID-19 who developed mucormycosis, a dangerous fungal infection, had diabetes. Mucormycosis is a rare but serious COVID-19 complication. People with unmanaged diabetes made up 67% of those with this dangerous complication.

Visit our COVID-19 hub to learn more.

Research has not yet determined whether COVID-19 can cause diabetes, but several studies suggest that a person may have an increased risk of being diagnosed with either type 1 or type 2 diabetes after having COVID-19.

For example, in a population-level study of children who received a diagnosis of COVID-19 in 2020 or 2021, researchers found that 0.04% of children had a diabetes diagnosis after a SARS-CoV-2 infection, compared to 0.03% of children who did not have a history of SARS-CoV-2 infection but did have other respiratory infections.

A 2021 review emphasizes an increased risk of new and worsening diabetes after COVID-19. The authors point to several potential culprits:

  • damage to the pancreas from COVID-19
  • the body’s stress response, including inflammation and a cytokine storm
  • use of medications, such as corticosteroids, that increase the risk of diabetes

The link between long COVID and diabetes may also be bidirectional.

According to 2022 findings presented at the 82nd Scientific Sessions of the American Diabetes Association, people with diabetes may be up to four times more likely to develop long COVID.

Diabetes, especially type 2 diabetes, may also be a symptom of long COVID or an effect of SARS-CoV-2 infection. The authors of a 2022 study estimate that COVID-19 increases the number of people with diabetes by an excess of 18 per 1,000.

People with diabetes have a higher risk of serious COVID-19 complications. This is especially true in people with other comorbidities, such as high blood pressure or heart disease.

A person should discuss treatment options with their doctor. Some early interventions, such as the following, may reduce the risk of serious COVID-19 complications:

  • antiviral treatments such as remdesivir and Paxlovid
  • monoclonal antibody therapies
  • interventions to manage diabetes symptoms, such as insulin or a change in the dosage of diabetes medications

People with diabetes and COVID-19 should not stop taking diabetes medication or change their dosage without consulting a doctor.

People with diabetes have a higher risk of COVID-19 complications. They should therefore choose to get a COVID-19 vaccine and remain up to date on all boosters. Most states prioritized people with diabetes for the vaccine.

There is no evidence that the vaccine harms people with diabetes, and the significant risks of COVID-19 outweigh any small side effects.

Read more about the COVID-19 vaccine here.

COVID-19 treatment is usually the same whether a person has diabetes or not. But people who have diabetes or other comorbidities may need early treatment.

It is also important that people manage diabetes by taking diabetes medication, exercising, and eating a low glycemic index diet.

Corticosteroids such as dexamethasone may increase the severity of diabetes or even trigger new cases of diabetes. People with diabetes should discuss these drugs’ risks and benefits with a doctor.

These strategies can help people avoid contracting SARS-CoV-2 or spreading it to others:

  • staying home from work if they feel sick
  • avoiding large crowds and unventilated spaces
  • getting the COVID-19 vaccine and staying up to date on all other vaccines
  • wearing a well-fitted mask over the mouth and nose in public, especially in high risk settings such as in large crowds
  • washing the hands frequently
  • avoiding direct contact with people who are ill or who have recently had COVID-19 exposure
  • moving activities outdoors when possible

COVID-19 may complicate diabetes and potentially even cause new diabetes.

It is important that people with diabetes know they are at risk and seek prompt care to reduce their risk of complications. Continuing to take diabetes medication is especially important because unmanaged blood sugar is a major risk factor for severe COVID-19.

People who are concerned about COVID-19 or diabetes should contact a healthcare professional. Early intervention can often help prevent serious complications.