Due to high rates of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection across the world and lockdown, there have been numerous changes in people’s lifestyles. Some factors such as lack of physical activity, stress, and improper eating habits have led to uncontrolled hyperglycemia, eventually resulting in weight gain and sharp fluctuations in blood glucose levels in patients with diabetes. Statistics indicate that nearly 60-70% of patients in India have uncontrolled glycemia. Moreover, a steep rise in diabetes-related complications has been witnessed. Furthermore, new-onset hyperglycemia with or without diabetes and acute metabolic decompensation of pre-existing diabetes associated with Covid-19 have garnered considerable attention in the recent past. Emerging data indicate that Covid-19 may trigger the onset of diabetes in healthy individuals and cause severe complications of pre-existing diabetes. Although the precise mechanism remains obscure, the researchers have unraveled that angiotensin-converting enzyme 2 that binds to SARS-CoV-2 allowing the virus to enter human cells, is not only present in the lungs but also in the pancreas, the small intestine, the fat tissue, the liver, and the kidney. It has been proposed that the virus may cause many complex dysfunctions of glucose metabolism by entering these tissues.

This warrants the need for optimal glycemic control to reduce the risk of threatening metabolic complications in this patient population. With regard to this, metformin therapy has been suggested to be a beneficial option. The use of this drug remarkably accelerates glucose clearance and reduces hyperglycemia. Studies have reported a positive impact of high dose metformin on all glycemic pentad parameters including maximum HbA1c reduction, maximum fasting plasma glucose reduction, least postprandial glucose elevation,better mean 24-hour glucose control,and much-reduced risk of hypoglycemia. Moreover, it can reduce inflammation, act as an antioxidant, and alter the gut microbiota’s composition. These properties may help in combating the cytokine storm, frequently seen in patients with diabetes and Covid-19. It is noteworthy that its use has also been associated with a fourfold risk reduction in in-hospital mortality. Besides, the immune-modulating properties of this drug may help in improving patients’ outcomes. According to a recent diabetes management algorithm, metformin therapy in Covid-19 patients with hyperglycemia (previously diagnosed or undiagnosed)should be escalated if required and if there are no other contraindications or abdominal distress in the patient.

To conclude, due to the pleiotropic benefits of metformin, it can be a real game-changer. It could favourably influence the clinical outcomes of patients with diabetes and help in reducing the risk of severe Covid-19.

References

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