COVID-19 and type 2 diabetes mellitus—Interrelation, outcome, and therapeutic strategies
DOI:
https://doi.org/10.14748/nsfsc911Keywords:
COVID-19, SARS-CoV-2, comorbidities, diabetes, hyperglycemiaAbstract
Introduction: COVID-19 is caused by SARS-CoV-2. Individuals with type 2 diabetes mellitus are a main risk group for its severe and often fatal course.
Aim: In this review we examine the pathogenetic relationship, clinical outcome, and current therapeutic strategies in patients with type 2 diabetes mellitus, suffering from COVID-19.
Material and Methods: Data from international studies were integrated, with particular focus on hospitalized patients from the targeted group. Pathophysiological mechanisms, risk factors, and outcomes were systematically analyzed.
Results and Discussion: Diabetes mellitus is associated with impaired innate and adaptive immunity, chronic systemic inflammation, endothelial dysfunction, and a prothrombotic state. Hyperglycemia and insulin resistance increase ACE2 and furin expression, facilitating viral entry and its replication. In diabetic patients with COVID-19, higher rates of hospitalization, intensive care admission, and the need for mechanical ventilation are frequently reported. Optimal glycemic control is crucial, as both hyper- and hypoglycemia worsen the outcomes. Insulin remains the preferred therapeutic agent in hospitalized patients, with emerging evidence supporting the use of SGLT-2 and DPP-4 inhibitors.
Conclusion: Type 2 diabetes mellitus is a significant risk factor for severe COVID-19. The underlying pathogenesis involves a complex interplay of immune dysfunction, chronic inflammation, endothelial damage, and metabolic regulation, indicating bidirectional relationship. Achieving optimal glycemic control, managing comorbidities, and ensuring early medical intervention are essential strategies for improving prognosis in this high-risk population.
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