Use of tocilizumab in COVID-19 pneumonia hospitalized patients. Cohort study

INTRODUCTION: In COVID 19, an aggressive inflammatory response called cytokine release storm has been described. It is mainly mediated by the activation of Interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α), mainly observed in critically ill patients. Among the multiple treatments proposed throughout these two years of pandemic, we highlight the use of Tocilizumab (TCZ). OBJECTIVES: To evaluate in-hospital mortality, transfer to critical care unit (CCU), invasive mechanical ventilation requirement (IMV), and hospital stay in patients treated with TCZ versus conventional treatments (CT). METHODS: Retrospective, descriptive, and analytical cohort study. Hospitalized patients, May to July 2021. Branches: treated with TCZ versus CT. Statistical analysis: Epi Info 7.2. RESULTS: Ninety patients, 51 TCZ branch and 39 CT branch. Age 48.2 years (± 11.7), males 74 (82.2%). Comorbidities 66 (73.3%): High blood pressure (HBP) 32 (35.6%), Diabetes mellitus 13 (14.4%), BMI > 30, 51 (56.7%). Medical Clinic Admission (MC) 85 (94.4%). Days post-symptom onset 7.9 (± 2.6). Severity of COVID 19: severe 61 (67.8%), critical 26 (28.9%). CCU admission 26 (29.9%). IMV 16 (17.8%). Deaths 7 (7.9%). Hospital stay 12.9 (± 6.6) days. Comparative analysis TCZ versus CT: MC admission 50 (98%) versus 35 (89.7%) p .08. CCU admission 12 (23.5%) versus 14 (38.9%) p .1. IMV 4 (7.8%) versus 12 (30.8%) p .005. Death 1 (2.0%) versus 6 (15.8%) p .02. Mortality in univariate analysis (p < .05): APACHE II, BMI > 30, TCZ, IMV, and CCU admission. TCZ was a protective factor against RR of death .86 (.74–.99). The IMV requirement was a RR factor for death 2.0 (1.23–3.42). Cox logistic regression, independent survival factors: use of TCZ, absence of obesity, and no IMV, p .0000. CONCLUSIONS: IMV was found to be a risk factor for mortality. TCZ did not show a decrease in CCU requirement, but it did prove to be a protective factor against mortality. However, this is a non-randomized study so it should be interpreted with caution.