ABSTRACT
SARS-CoV-2 continues to pose a major challenge to scientists and clinicians. We examined the significance of the serum concentrations of vitamin D, albumin, and D-dimer for the severity of the clinical picture and mortality in COVID-19. MATERIALS AND METHODS: A total of 288 patients treated for COVID-19 infection participated in the research. The patients were treated in the period from May 2020 to January 2021. All patients were divided based on the need for oxygen therapy (Sat > 94%) into patients with mild or severe clinical pictures. The biochemical and radiographic parameters of the patients were analyzed. Appropriate statistical methods were used in the statistical analysis. RESULTS: In patients with COVID-19 with confirmed severe clinical pictures, lower values of serum albumin (p < 0.0005) and vitamin D (p = 0.004) were recorded, as opposed to elevated values of D-dimer (p < 0.0005). Accordingly, the patients with fatal disease outcomes had lower levels of albumin (p < 0.0005) and vitamin D (p = 0.002), while their D-dimer (p < 0.0005) levels were elevated. An increase in the radiographic score, as a parameter for assessing the severity of the clinical picture, was accompanied by a decrease in serum albumin (p < 0.0005) and a simultaneous increase in D-dimer (p < 0.0005), without a change in the vitamin D concentration (p = 0.261). We also demonstrated the interrelations of the serum levels of vitamin D, albumin, and D-dimer in patients with COVID-19 as well as their significance as predictors of the outcome of the disease. CONCLUSION: The significance of the predictive parameters in our study indicates the existence of an important combined role of vitamin D, albumin, and D-dimer in the early diagnosis of the most severe patients suffering from COVID-19. Reduced values of vitamin D and albumin, in combination with elevated values of D-dimer, can be timely indicators of the development of a severe clinical picture and death due to COVID-19.