Clinical comparison between epidemic waves in COVID-19 hospitalized patients

Abstract

Introduction: COVID-19 is responsible for several epidemic waves worldwide with different clinical and prognostic evolution.

Objective: To describe the evolution, treatment and prognosis of patients admitted for COVID-19 according to 2020’s different epidemic waves.

Methods: 188 consecutive patients were selected during the first wave (March-May) and 233 during the second one (July-December). Clinical, epidemiological, prognostic and therapeutic variables were collected.

Results: Patients in the first wave were older (71±14 vs 67±15 years, p=0.01), suffered more hypertension (64% vs 54%, p=0.04), chronic kidney disease (20% vs 12%, p=0.036) and had lower PaO2/FiO2 at admission (261±101 vs 289±79, p<0.001). Received drugs between waves were different: Azithromycin (45% vs 10%), Hydroxychloroquine (89% vs 0.4%), Tocilizumab (17% vs 52%, Remdesivir (0% vs 26%) and Dexamethasone (0% vs 75% (p<0.001 for all)). ICU admissions decreased (32% vs 13%, p<0.001), as well as invasive or non-invasive mechanical ventilation requirement (23% vs 4%, p<0.001; 27% vs 18%, p=0.03; respectively), with no difference in high-flow oxygen therapy (34% vs 37%, p=0.6). Hospital length was shorter during the second wave (21±20 vs 12±12 days, p<0.001), with no difference in hospital mortality (16% vs 13%, p=0.4), after 30 days of discharge (19% vs 16%, p=0.4) or in the first 30 days readmissions (10% vs 8%, p=0.5).

Conclusions: During the second wave the therapeutic strategy changed which traduced into a lower proportion of ICU admissions, invasive mechanical ventilation requirement and shorter hospital stay. No differences in mortality or hospital readmissions were observed.

Supported in part by CIBERESUCICOVID (COV20/0011)