Elevated D-dimer and Adverse In-hospital Outcomes in COVID-19 Patients and Synergism with Hyperglycemia

AIM: One of the most common laboratory findings in COVID-19 patients has been observed to be hypercoagulability with elevated D-dimer levels. An activation of thrombosis may be generated by hyperglycemia. We aimed to explore the association between D-dimer and in-hospital outcomes, and evaluate the synergistic effect between elevated D-dimer and hyperglycemia on COVID-19 prognosis. METHODS: A retrospective cohort study was undertaken with 2467 COVID-19 inpatients. D-dimer and fasting blood glucose (FBG) on admission and adverse in-hospital outcomes (events of death and aggravated severity) were collected. Cox proportional risk model was performed to assess the association of D-dimer and adverse in-hospital outcomes, and the combined effects of D-dimer and FBG. RESULTS: Among these COVID-19 patients, 1100 (44.6%) patients had high D-dimer (≥0.50 mg/L). Patients with high D-dimer were older, with higher FBG (≥7.00 mmol/L), and had significantly higher adjusted risk of adverse in-hospital outcomes when comparing with those who with D-dimer<0.50 mg/L (hazard ratio, 2.73; 95% confidence interval, 1.46–5.11). Moreover, patients with high FBG and D-dimer levels had an increasing risk (hazard ratio, 5.72; 95% confidence interval: 2.65–12.34) than those with normal FBG and D-dimer. CONCLUSION: Risk of adverse in-hospital outcomes is higher among patients with high D-dimer levels. Additionally, this study found for the first time that elevated D-dimer and hyperglycemia had a synergistic effect on COVID-19 prognosis, and this risk was independent of diabetes history.