Lymphopenia is commonly present in patients with COVID-19. We sought to determine if lymphopenia on admission predicts COVID-19 clinical outcomes. A retrospective chart review was performed on 4485 patients with laboratory-confirmed COVID-19, who were admitted to the hospital. Of those, 2409 (57.3%) patients presented with lymphopenia (absolute lymphocyte count < 1.1 × 10⁹/L) on admission, and had higher incidences of ICU admission (17.9% versus 9.5%, p < 0.001), invasive mechanical ventilation (14.4% versus 6.5%, p < 0.001), dialysis (3.4% versus 1.8%, p < 0.001) and in-hospital mortality (16.6% versus 6.6%, p < 0.001), with multivariable-adjusted odds ratios of 1.86 (95% confidence interval [CI], 1.55–2.25), 2.09 (95% CI, 1.69–2.59), 1.77 (95% CI, 1.19–2.68), and 2.19 (95% CI 1.76–2.72) for the corresponding outcomes, respectively, compared to those without lymphopenia. The restricted cubic spline models showed a non-linear relationship between lymphocyte count and adverse outcomes, with an increase in the risk of adverse outcomes for lower lymphocyte counts in patients with lymphopenia. The predictive powers of lymphopenia, expressed as areas under the receiver operating characteristic curves, were 0.68, 0.69, 0.78, and 0.79 for the corresponding adverse outcomes, respectively, after incorporating age, gender, race, and comorbidities. In conclusion, lymphopenia is a useful metric in prognosticating outcomes in hospitalized COVID-19 patients.

Background: First responders (FRs) may have a significant risk of coronavirus 19 (COVID-19) infection than the general population due to job-related exposures. We aimed to determine the prevalence and exposure patterns of COVID-19 among FRs. Methods: Between March and April 2020, FRs in Broward County, Florida, were screened for COVID-19 infection by real-time reverse transcription polymerase chain reaction assay using nasopharyngeal swabs. Demographics and COVID-19 positive rate of the FRs were summarized. Results: A total of 3375 FRs were screened for COVID-19 infection. The median age of FRs tested was 42 years (IQR 33–52 years), and 1464 (43.4%) were men. A total of 2902 (85.9%) were asymptomatic, and 473 (14.1%) reported symptoms associated with COVID-19. Overall, 289 (8.6%) were positive, with the highest rates among the age between 25 and 49 years. Of those testing positive, 235 (81.3%) were asymptomatic. Fourteen days after their first positive test, 81 (69.8%) of the 116 asymptomatically infected FRs were negative, and 35 (30.2%) remained positive and asymptomatic. Conclusions: The FRs in Broward County, FL, had an overall infection rate of 8.6% at the time of COVID-19 testing, and asymptomatic FRs accounted for 81.3% of infection. Active surveillance should be focused on the asymptomatic FRs with COVID-19.

The COVID-19 Omicron variant has imposed a tremendous burden on healthcare services. We characterized the types of the Omicron variant-associated hospitalizations and their associations with clinical outcomes. Consecutive adults hospitalized with COVID-19 during the Omicron variant surge period of 1–14 January 2022, were classified into one of three groups based on their clinical presentations on admission: Group 1—primary COVID-19; Group 2—extrapulmonary manifestations of COVID-19; and Group 3—incidental COVID-19. Of the 500 patients who were hospitalized, 51.4% fell into Group 1, 16.4% into Group 2, and 32.2% into Group 3. The patients in Groups 1 and 2 were older, with higher proportions of comorbidities than patients in Group 3. The Group 1 patients had the highest mortality rate (15.6%), followed by Group 2 (8.5%), and Group 3 (0.6%), with adjusted odds ratios (OR) of 22.65 (95% confidence interval [CI], 2.75–239.46; p = 0.004) and 10.95 (95% CI, 1.02–117.28; p = 0.048), respectively, compared to Group 3. Those in Group 1 showed a greater utilization of intensive care services (15.9%), followed by Group 2 (10.9%), and Group 3 (2.5%), with adjusted ORs of 7.95 (95% CI, 2.52–25.08; p < 0.001) and 5.07 (95% CI, 1.34–19.15; p = 0.017), respectively, compared to Group 3. The patients in Groups 1 and 2 had longer hospitalization stays than the patients in Group 3 (p < 0.001 and p = 0.002, respectively). Older age (≥65 years) was an independent factor associated with longer hospital stays (OR = 1.72, 95% CI, 1.07–2.77). These findings can help hospitals prioritize patient care and service planning for future SARS-CoV-2 variants.

Objective: The objective of the study was to establish an AI-driven decision support system by identifying the most important features in the severity of disease for Intensive Care Unit (ICU) with Mechanical Ventilation (MV) requirement, ICU, and InterMediate Care Unit (IMCU) admission for hospitalized patients with COVID-19 in South Florida. The features implicated in the risk factors identified by the model interpretability can be used to forecast treatment plans faster before critical conditions exacerbate. Methods: We analyzed eHR data from 5371 patients diagnosed with COVID-19 from South Florida Memorial Healthcare Systems admitted between March 2020 and January 2021 to predict the need for ICU with MV, ICU, and IMCU admission. A Random Forest classifier was trained on patients’ data augmented by SMOTE, collected at hospital admission. We then compared the importance of features utilizing different model interpretability analyses, such as SHAP, MDI, and Permutation Importance. Results: The models for ICU with MV, ICU, and IMCU admission identified the following factors overlapping as the most important predictors among the three outcomes: age, race, sex, BMI, diarrhea, diabetes, hypertension, early stages of kidney disease, and pneumonia. It was observed that individuals over 65 years (‘older adults’), males, current smokers, and BMI classified as ‘overweight’ and ‘obese’ were at greater risk of severity of illness. The severity was intensified by the co-occurrence of two interacting features (e.g., diarrhea and diabetes). Conclusions: The top features identified by the models’ interpretability were from the ‘sociodemographic characteristics’, ‘pre-hospital comorbidities’, and ‘medications’ categories. However, ‘pre-hospital comorbidities’ played a vital role in different critical conditions. In addition to individual feature importance, the feature interactions also provide crucial information for predicting the most likely outcome of patients’ conditions when urgent treatment plans are needed during the surge of patients during the pandemic.

Lymphopenia has been reported as a relatively frequent finding in patients with coronavirus disease 2019 (COVID-19). This study aimed to assess the use of absolute lymphocyte count (ALC) as a prognostic biomarker for disease severity and clinical outcomes. A cohort of adult patients with COVID-19 admitted to Memorial Healthcare System, Hollywood, Florida from March 7, 2020 to January 18, 2021 was retrospectively analyzed. An absolute lymphocyte count (ALC) < 1.1 × 10⁹/L was used as cutoff point to define lymphopenia. Correlations of ALC upon admission with age and serum levels of C-reactive protein, interleukin-6, lactate dehydrogenase, and creatinine were analyzed. Univariate and multivariate regression models were developed to assess the association of lymphopenia with the risk of ICU admission and clinical outcomes. 4,485 hospitalized patients were included in the final analyses. Median age was 61 (interquartile range, 47-73) years and 2,311 (51.5%) were men. Lymphopenia was more frequent in patients admitted to the ICU compared to those that were not admitted to the ICU, with an odds ratio of 2.14 (95% confidence interval [CI], 1.78-2.56, p < .0001) (Figure 1). The actual value of the ALC was negatively correlated with age and serum levels of C-reactive protein, interleukin-6, lactate dehydrogenase, and creatinine (all p < 0.005). Patients with lymphopenia (n=2,409) compared to those without lymphopenia (n=2,076) had multivariable-adjusted odds ratios of 1.85 (95% CI, 1.53-2.24) for ICU admission, 2.08 (95% CI, 1.67-2.58) for intubation, 1.98 (95% CI, 1.31-3.00) for development of acute kidney failure, and 2.23 (95% CI, 1.79-2.79) for in-hospital mortality (Table 1). Analyses were adjusted for age, gender, race, hypertension, diabetes, chronic obstructive pulmonary disease, chronic kidney disease, coronary artery disease, malignancy, obesity, and smoking. Lymphopenia in adult COVID -19 hospitalized patients was associated with increased risk of disease severity (as evidenced by need for ICU admission) and poor clinical outcomes. Absolute lymphocyte count may help with prognostication in individuals hospitalized with COVID-19. All Authors: No reported disclosures

Nationally, the 18–49 years old age group are less likely to be vaccinated compared to those 50 years and older. Data describing the risk of COVID-19 severe illness that requires hospitalization among younger healthy adults is limited. In an effort to underscore the importance of vaccination and provide data that may influence COVID-19 risk perception, COVID-19 data of a sample of hospitalized non-elderly age group who clinically may not be considered as high risk for severe COVID-19 illness are presented. Specifically, this retrospective chart review (spanning the period of March 2020 to September 2021) provides a descriptive analysis examining the characteristics, vaccination status and outcomes of adults who were hospitalized at Memorial Healthcare System with laboratory-confirmed COVID-19. The study’s data focuses on non-pregnant adults, aged 18–49 years old, without underlying conditions and with no reported history of smoking. As a sub-analysis, data on young and otherwise healthy pregnant females who were hospitalized with COVID-19, as well as data stratified by the pre-Delta and Delta variant dominant period are also presented. There was a total of 482 young and otherwise healthy non-pregnant adults who were hospitalized with COVID-19. Overall, more than 13% of our study population had severe COVID-19 disease. Further, a higher proportion of unvaccinated patients had severe COVID-19 compared to those who received at least one dose of the vaccine. All ventilator or ECMO placements, 30-day readmissions and deaths occurred among unvaccinated patients.