Diagnostic Value of D Dimer Serum Marker in COVID 19 Patients

Introduction: COVID 19 Pandemic posed devastating consequences for the healthcare community regarding morbidity, mortality, and resource utilization in 2020. Clinicians are studying all aspects of the disease, intending to provide the most efficient patient care. Monitoring in-patients with a proven COVID 19 disease diagnosis has been challenging and aided by tracking serum inflammatory markers. We aimed to study D Dimer as a potentially important serum marker and verify if it correlated to clinical patient outcomes. Our primary outcome is in-patient mortality, and the secondary outcome is respiratory failure requiring ventilator use and hospital length of stay. Methods: A single-center, retrospective observational study obtaining data from electronic medical records of all COVID-19 positive patients admitted to an urban tertiary care center in New Jersey between March 15th, 2020 to May 6th, 2020. A total of 1210 patients were identified with primary in-patient diagnosis of COVID-related acute illness during the study period. Among these patients, 928 patients were included in this study who had at least one recorded D dimer value during their hospitalization. In patients with multiple values, the highest value was taken for the study purpose. Two sample t-test and a Pearson correlation coefficient test were used to measure relationships between variables. R studio version 1.3.1073 was used for data analysis. Results: The mean age of patients was 60 years, and 571(61.5%) were male gender. The ethnicity distribution of patients was 24.3% Caucasian, 19% African American, and 49% Hispanic. Major symptoms on presentation were cough(68.9%), fever (58%), and shortness of breath(74.7%). Notable comorbidities among patients were Hypertension (57.3%), Diabetes Mellitus ( 38.9%), Obesity (39%), and Chronic kidney disease (9.91%). The mean D dimer values for patient groups discharged and died were 4.89 and 10.14 mcg/ml, respectively, with the t-test showing a significant difference between the groups(p value:0.0001, CI: -6.16:-4.34). D dimer values were also significantly different between the groups with ventilator use and without(p value:0.0001, CI:6.23-7.17). D dimer also predicted a higher length of stay with increasing value with a correlation coefficient of 0.14( p value:0.0001, CI: 0.08-0.20). Conclusion: Serum D dimer value is a critical laboratory value to trend and helps navigate an inpatient stay for COVID 19 patients. Clinical correlation with fibrinogen, LDH would give us more information regarding underlying hematological dysfunction. Increasing d dimer value in patients positively correlated with a higher risk of in-patient mortality, ventilator use, and increased length of stay in our study population.