Associations between Inflammatory Markers, Micronutrients, and Disease Severity in COVID-19 Patients with Type 2 Diabetes Mellitus

Abstract

The management of treatment strategies in COVID-19 is critical, especially in patients with type 2 diabetes. Non-enzymatic glycation of transmembrane protease serine 2 and angiotensin-converting enzyme 2 during COVID-19 in patients with diabetes may exacerbate immune dysregulation and inflammation. Elevated inflammatory cytokines such as IL-1, IL-2, IL-6, IL-7, and IL-10, tumor necrosis factor-α, interferon-γ, granulocyte-macrophage colony-stimulating factor, and monocyte chemoattractant protein-1 have been observed in COVID-19 patients. This review aims to assess the relationship between inflammatory markers, including C-reactive protein, and micronutrients (vitamins D and C, zinc, and copper) with the severity of COVID-19 infection in patients with type 2 diabetes. A narrative review was conducted through a comprehensive literature search of English-language articles published between 2000 and 2025. The databases searched included PubMed, Scopus, the ISI Web of Science, Cochrane, and Embase. Search terms included COVID-19, infections, type 2 diabetes mellitus, interleukins, and micronutrients. English-language scientific articles, systematic reviews, and meta-analyses were included, while studies lacking sufficient information, letters, comments, and editorials were excluded. Evidence suggests that immune-boosting components such as proteins, vitamins, and minerals can enhance immunity to infections. Vitamins D and C, zinc, and copper play supportive roles in immune function, potentially modulating the inflammatory response in COVID-19 patients with type 2 diabetes. High levels of inflammatory cytokines correlate with increased disease severity in this population. Understanding the interplay between inflammatory markers and micronutrients may guide improved therapeutic strategies for managing COVID-19 in diabetic patients. Further research is warranted to clarify these relationships and optimize clinical outcomes.