Comparison of Patient Clinical characteristics and Outcomes Between Different COVID-19 Peak Periods: A Single Center Retrospective Propensity Matched Analysis

Introduction While Coronavirus disease 2019 (COVID-19) specific treatments have been instituted, overall mortality rates among hospitalized patients remain significant. Our study aimed to evaluate patient clinical characteristics and outcomes comparing the different COVID-19 infection peak periods. Methods This is a retrospective study of all adult patients hospitalized with a confirmed diagnosis of COVID-19 between March 1 to April 24, 2020 and November 1 to December 31, 2020, which corresponded to the first and second waves of COVID-19 infection in our institution, respectively. Demographic and clinical characteristics of the patients were compared and used for propensity matching. Clinical outcomes, such as need for intubation, renal replacement therapy and inpatient mortality were subsequently compared between the two groups. Results Patients in the second COVID-19 wave had a significantly higher body mass index (32.58 vs 29.83, p <0.001), as well as prevalence of asthma (14% vs 8%, p=0.019) and chronic kidney disease (42% vs 18%, p <0.001). Almost all patients in the second COVID-19 wave received corticosteroid treatment (99% vs 30%, p <0.001), and significantly more patients received remdesivir (43% vs 2%, p <0.001). Meanwhile, none of the patients in the second COVID-19 wave were treated with tocilizumab or hydroxychloroquine. Differences in clinical outcomes, such as need for renal replacement therapy or intubation, and median length of stay were not statistically significant. Inpatient mortality remained largely unchanged between the two COVID-19 peak periods. Discussion/ Conclusion In our institution, after propensity matched analysis, clinical outcomes such as need for renal replacement therapy, intubation and inpatient mortality remained unchanged between the two COVID-19 peak periods.