Comparative Study on the Effect of Vitamin D Deficiency on Platelet Indices in Covid-19 and Hepatitis C Patients; an Observational Comparative Study Publisher



Motaghi M ; Ghaffari K ; Mansori M ; Ghasemi A
Source: Health Science Reports Published:2026

Abstract

Background and Aims: Despite growing interest in the role of vitamin D in various infectious diseases, limited evidence exists regarding its association with platelet (PLT) parameters in patients with COVID-19 and Hepatitis C Virus (HCV) infection. This study aims to assess the relationship between serum vitamin D levels and PLT indices in patients with COVID-19 and chronic HCV. Methods: The study included 113 patients with confirmed COVID-19 and 97 patients with chronic HCV infection. All participants were classified into two subgroups based on their vitamin D status (deficient vs. non-deficient). The chi-square test (χ2) or Fisher exact test was used to compare the results between the two groups. Results: Patients with COVID-19 had significantly lower levels of vitamin D compared with HCV patients (p < 0.001). PLT counts were lower in the COVID-19 group, and MPV, PDW, and inflammatory markers (PLR, MPR, and MLR) were significantly higher. Also, a significant negative correlation was observed between vitamin D levels and MPV in both groups (p < 0.001). In patients with vitamin D deficiency, PLT and inflammatory changes were more pronounced in COVID-19 than in HCV. Conclusion: The results of this study showed that COVID-19 patients had lower vitamin D levels, lower PLT counts, and higher indices of platelet activation compared with HCV patients. These changes are associated with the severity of the inflammatory response in COVID-19 and could be part of the mechanisms that cause thrombotic complications in this disease. © 2026 The Author(s). Health Science Reports published by Wiley Periodicals LLC.