BackgroundCoronavirus disease 2019 (COVID-19) infection can vary from asymptomatic infection to multi-organ dysfunction. The most serious complication of infection with COVID-19 is death. Various comorbid conditions and inflammatory markers have been associated with an increased risk of mortality, specifically within the immediate post-infection period; however, less is known about long-term mortality outcomes. ObjectivesOur objective is to determine risk factors associated with six-month mortality in hospitalized COVID-19 patients. MethodsThis is a single-institution, retrospective study. We included patients hospitalized with COVID-19 from the University of Toledo Medical Center in Toledo, Ohio, who were admitted from March 20, 2020, to June 30, 2021. This study was approved by a biomedical institutional review board at the University of Toledo. Patients with available pre-stored blood samples for laboratory testing were included, and hospital charts were assessed up to six months from the date of a positive COVID-19 test result. Two groups were created based on the mortality outcome at six months from COVID-19 positive test results: survivors and nonsurvivors. The clinical variables or outcomes and laboratory values were compared between the two groups using non-parametric methods due to the small sample size and non-normality of the data. Either the Mann-Whitney U-test for continuous variables or Fisher's exact test for categorical variables was used for statistical analysis. ResultsLactate dehydrogenase (LDH) and D-dimer levels on admission were found to be significantly higher in nonsurvivors than in survivors. The median high D-dimer level in non-survivors was 5.96 micrograms/milliliter (μg/mL) (interquartile range (IQR): 3.95-11.29 μg/mL) vs 1.82 μg/mL (IQR 1.13-5.55 μg/mL) in survivors (p = 0.019). Median LDH levels were also higher in non-survivors vs survivors, i.e., 621.00 international units per liter (IU/L) (IQR 440.00-849.00 IU/L) vs 328.00 IU/L (IQR 274.00-529.00 IU/L), respectively (p = 0.032). The demographic profile, comorbidity profile, and laboratory data (typically associated with short-term mortality, inflammation, and organ dysfunction) were similar between survivors and non-survivors, except for LDH and D-dimer. ConclusionHigher LDH and D-dimer levels on admission were found to be associated with an increased six-month mortality rate in hospitalized COVID-19 patients. These hematologic data can serve as risk stratification tools to prevent long-term mortality outcomes and provide proactive clinical care in hospitalized COVID-19 patients.

Background: Coronavirus disease 2019 (COVID-19) infection is associated with an increased risk of arterial thromboembolic events (ATE) and venous thromboembolic events (VTE). Hypercoagulability associated with COVID-19 infection is multifactorial, and underlying pathogenic mechanisms potentially responsible for thrombosis include inflammation resulting in endothelial damage, platelet activation and the presence of antiphospholipid antibodies (APAs). Antiphospholipid antibody syndrome is one of the very few causes which is associated with venous and arterial thromboembolic events. COVID-19 patients have a high prevalence of APAs as well as both ATE and VTE, but their clinical significance in COVID-19 patients is not fully understood yet.Objectives: In this study, we intend to find the prevalence of APAs in hospitalized COVID-19 patients at the time of diagnosis and determine whether their presence has any clinical significance.Methods: This is a retrospective single-institution study involving patients hospitalized for the management of COVID-19 infection at The University of Toledo Medical Center. After obtaining approval from the biomedical institutional review board at The University of Toledo, antiphospholipid antibody (APA) testing was done on pre-stored blood samples of these patients and hospital charts were reviewed till six months from the positive COVID-19 test result. Two groups were created based on the patients' APA testing results (APA positive and APA negative) and used for statistical comparison. Any patients with positive lupus anticoagulant (LA) or abnormal titers APA antibodies were labeled as positive. Demographic data, prognostic outcomes and laboratory values were compared either using Mann-Whitney U-test for continuous variables or Fisher's exact test for categorical variables.Results: The prevalence of APAs in hospitalized COVID-19 patients at the time of diagnosis was 39.3% in this study. There was no difference in demographic variables between the APA-positive and APA-negative groups. The prevalence of APAs was higher in smokers, where 91% of the APA-positive patients were smokers. There was no statistically significant difference in prognostic outcomes including six-month mortality between APA-positive and APA-negative patients. The comorbidity profile was the same in the two groups. APA-positive patients were found to have lower nadir of absolute lymphocyte count and higher nadir levels of C-reactive protein during hospitalization.Conclusions: The prevalence of APA positivity in hospitalized COVID-19 patients is higher in our study than in historical studies involving non-COVID-19 hospitalized patients, particularly in smokers. However, there is no correlation between APA positivity and prognostic outcomes including six-month mortality. At this point, it is unclear whether APAs are just bystanders or have a pathogenic role. Routine testing of APA in COVID-19 patients is not indicated. Further prospective studies to elucidate the persistence and clinical implications of APAs are needed.