The global health crisis caused by coronavirus disease 2019 (COVID-19) has highlighted the complex relationship between viral infections and pre-existing health conditions. Diabetes mellitus, a widespread metabolic disorder, significantly influences the severity and outcomes of COVID-19. This article explores how COVID-19 and diabetes interact, affecting each other.
Why Diabetes Increases COVID-19 Severity
Individuals living with diabetes face a higher risk of developing severe complications and experiencing worse outcomes from COVID-19. This increased vulnerability stems from several physiological factors common in people with diabetes. Chronic inflammation, a persistent low-grade inflammatory state, is frequently observed in diabetic individuals, which can be exacerbated by a viral infection. When SARS-CoV-2, the virus causing COVID-19, enters the body, this existing inflammation can quickly escalate into an overwhelming immune response, sometimes referred to as a “cytokine storm.”
Diabetes often impairs the body’s immune responses, making it less effective at fighting off infections. High blood sugar levels can compromise both innate and adaptive immunity, reducing the ability of immune cells to function properly and increasing viral replication. This weakened immune defense contributes to the heightened risk of severe pneumonia, acute respiratory distress syndrome (ARDS), and multi-organ failure in diabetic patients infected with COVID-19.
The SARS-CoV-2 virus enters human cells by binding to the angiotensin-converting enzyme 2 (ACE2) receptor. Research suggests that individuals with hyperglycemia, or high blood sugar, may have increased expression of these ACE2 receptors, potentially facilitating greater viral entry into cells. Co-existing conditions often associated with diabetes, such as cardiovascular and kidney disease, further compound the risk by placing additional stress on the body during infection. Poor glycemic control, specifically elevated HbA1c levels (a measure of average blood sugar over several months), has been identified as a factor linked to higher mortality rates in diabetic patients with COVID-19.
COVID-19’s Impact on Diabetes Management and Onset
COVID-19 infection can directly influence blood sugar control in individuals who already have diabetes, leading to significant fluctuations. The body’s stress response to a severe infection triggers the release of hormones like glucocorticoids and catecholamines, which are known to raise blood sugar levels. This physiological stress can make it more challenging to maintain stable glucose control, even for those who typically manage their diabetes well.
Certain medications used to treat severe COVID-19, such as corticosteroids, also contribute to elevated blood glucose. These medications, while effective in reducing inflammation, can induce hyperglycemia, requiring careful monitoring and adjustment of diabetes treatment.
Beyond affecting pre-existing diabetes, there is also evidence suggesting that COVID-19 can lead to new-onset diabetes. This phenomenon has been observed in some individuals after infection, including both type 1 and type 2 diabetes.
One proposed mechanism for new-onset diabetes involves direct viral damage to pancreatic cells. The SARS-CoV-2 virus can infect cells in the pancreas, including beta cells that produce insulin, through ACE2 receptors, potentially impairing their function. Some studies indicate that the inflammatory stress of COVID-19 might push individuals with pre-diabetes past the diagnostic threshold. However, cases of severe hyperglycemia and diabetic ketoacidosis in patients without a prior diabetes diagnosis suggest potential direct effects on pancreatic beta cells or triggering of autoimmune responses.
Guidance for Individuals with Diabetes During the Pandemic
Proactive management and protective measures are important for individuals with diabetes during widespread illness. Maintaining strict blood sugar monitoring and control is a primary recommendation, as good glycemic control can lower the risk of severe complications if infected. Regular checking of blood glucose levels and adhering to prescribed medications, including insulin and oral antidiabetic drugs, are important.
Ensuring a sufficient supply of medications and testing supplies, ideally a 30- to 90-day supply, can help prevent disruptions in care. Maintaining a healthy lifestyle, encompassing a balanced diet and regular physical activity, supports overall health and immune function. Adequate hydration is also advised, with frequent small sips of liquids, especially if feeling nauseated.
Individuals with diabetes should seek prompt medical attention for any symptoms of illness, including those suggestive of COVID-19. Communicate regularly with healthcare providers, utilizing telehealth options when appropriate, to adjust medication regimens based on changes in diet, activity, or illness. Vaccination against COVID-19 and the flu is recommended to reduce the risk of severe illness. General hygiene practices, such as frequent hand washing, wearing masks, and practicing social distancing, also play a role in preventing infection.