The COVID-19 pandemic has reshaped global health in numerous ways, extending beyond its immediate respiratory impact. A significant area of ongoing scientific inquiry involves its potential long-term effects, particularly whether infection with SARS-CoV-2, the virus causing COVID-19, can lead to new cases of diabetes. Researchers worldwide are actively investigating this complex interplay between viral infection and metabolic health.
Emerging Evidence of a Connection
Observational studies and meta-analyses show a connection between COVID-19 infection and the development of new-onset diabetes or the worsening of existing diabetes. A systematic review of 20 studies, involving over 320,000 participants, estimated new-onset diabetes at 1.6% after 60 days from infection. This percentage increased to 2% in hospitalized patients, compared to 0.9% in the community.
Other research indicates that the risk of new-onset diabetes and hyperglycemia is significantly higher in individuals who have had COVID-19, with one meta-analysis suggesting a 1.75 times higher risk. The overall incidence was reported as 5%, with variables like age, ethnicity, and time of diagnosis influencing this rate. These findings suggest that COVID-19 may not only aggravate pre-existing diabetes but also potentially induce new cases in previously healthy individuals.
Potential Biological Mechanisms
The precise ways COVID-19 might contribute to diabetes are still under investigation, but several biological mechanisms are hypothesized. One theory involves direct damage to pancreatic beta cells, which produce insulin. The SARS-CoV-2 virus uses ACE2 receptors, present on these cells, to enter. Infection could impair insulin secretion, leading to elevated blood sugar levels.
Another proposed mechanism is systemic inflammation. COVID-19 can trigger a strong inflammatory response, which can lead to insulin resistance. Insulin resistance occurs when the body’s cells do not respond effectively to insulin, causing blood glucose levels to rise. The stress of a severe infection can also induce hyperglycemia, contributing to new-onset diabetes.
Impact on Different Diabetes Types
COVID-19 appears to affect both Type 1 and Type 2 diabetes, though mechanisms may differ. For Type 1 diabetes, an autoimmune condition where the immune system attacks insulin-producing beta cells, COVID-19 might act as a trigger. This could initiate or accelerate the autoimmune process in susceptible individuals. Some new-onset cases after COVID-19 have shown characteristics aligned with Type 1 diabetes, including severe hyperglycemia and diabetic ketoacidosis.
For Type 2 diabetes, involving insulin resistance and declining insulin production, COVID-19 could exacerbate existing resistance or unmask a predisposition. The inflammatory state with COVID-19 can worsen quickly in individuals with diabetes, potentially accelerating disease progression. While new-onset Type 2 diabetes appears more prevalent than Type 1 after COVID-19, both types warrant attention.
What to Know After COVID-19
Individuals who have recovered from COVID-19 should be aware of potential symptoms of new-onset diabetes, even if their initial infection was mild or asymptomatic. Common signs include increased thirst, frequent urination, unexplained weight loss, and fatigue. Monitoring blood sugar levels is important for those with pre-existing diabetes or at higher risk.
Maintaining a healthy lifestyle, including a balanced diet and regular physical activity, supports metabolic health. While not everyone who contracts COVID-19 will develop diabetes, vigilance and communication with healthcare providers are advisable if any concerning symptoms arise. Early detection and management of elevated blood sugar levels can help mitigate potential long-term complications.