Von willebrand factor level and activity in correlation with D-dimer level among COVID-19 patients in Saudi Arabia

BACKGROUND: Thrombosis and acute respiratory failure are among the leading causes of mortality in COVID-19 patients. The von Willebrand factor (VWF) is one of the main components in the blood coagulation system. It has been hypothesized that the increased VWF level results from vascular damage because VWF is stored in endothelial cells. Infection of endothelial cells with SARS-CoV-2 can stimulate the release of VWF. This study aimed to determine the level of VWF activity among the Saudi population affected by COVID-19 and investigate the correlation between VWF level and D-dimer level. MATERIALS AND METHODS: This is an analytical, retrospective, observational study conducted in a single-center tertiary hospital at King Fahad Military Medical Complex (KFMMC). A study sample of 80 hospitalized patients (aged ≥18 years) diagnosed with COVID-19 confirmed by nasopharyngeal SARS-COV was randomly included in this study. Frozen blood samples were used to measure VWF antigen (Ag) level and activity for all patients. Historical data on hemostasis markers such as platelets (PLTS), fibrinogen, and D-dimer were obtained retrospectively, as well as demographic and clinical data. RESULTS: Data of 80 patients were analyzed to assess VWF Ag level and activity in correlation to D-dimer level. The mean age of the patients was 58.3 (standard deviation 16.18), with nearly two-thirds being females (62.6%). The most common comorbidities were arterial hypertension (67.5%), diabetes (56.3%), and dyslipidemia (22.5%). Only 10% of patients were obese. The mean values of were 3.25 for D-dimer, 3.55 for fibrinogen, 226.4 for PLTS, 9.88 for white blood cell, 237.04 for VWF Ag, 253.21 for VWF activity, and 70.45 for C-reactive protein. Pearson's correlation coefficient revealed that the correlation between D-dimer and VWF Ag and D-dimer and VWF activity was statistically insignificant (P > 0.05). Only six patients had overt thrombosis, but this has no significant correlation with VWF Ag, activity, D-dimer, or platelet count. VWF Ag and activity were higher in intensive care unit (ICU) than non-ICU patients. However, it is not significant statistically. VWF Ag and activity were significantly higher in deceased patients than in survivors. CONCLUSIONS: The results of this study showed that there was no significant correlation between VWF Ag and activity with D-dimer among Saudi patients with confirmed COVID-19.