Abstract: [ Chest Infections Research Letter ] The Minimal Effect of Zinc on the Survival of Hospitalized Patients With COVID-19 An Observational Study To the Editor: Zinc is an investigational agent against coronavirus disease 2019 (COVID-19) and has known preventative and therapeutic roles in other infections.1-3 Zinc deficiency is associated with lower survival among older patients with pneumonia and predisposes to other viral infections.3 Established risk factors for critical COVID-19, including older age, diabetes mellitus, and cardiovascular disease, are also associated with zinc deficiency.2 The antiviral and immunomodulatory effects of zinc have made it a candidate against severe acute respiratory Methods In this single-institution retrospective study, we assessed the survival of hospitalized patients with COVID-19 treated with vs without zinc sulfate. This study was conducted in accordance with the amended Declaration of Helsinki. This study’s protocol was approved and was granted a waiver of informed consent by the hospital board on April 15, 2020, based on its retrospective design and the lack of identifying information to be published, collected, or analyzed. Data of all patients with COVID-19 (N ¼ 242) admitted at the Hoboken University Medical Center until April 11, 2020, were retrospectively collected on April 21, 2020. COVID-19 was confirmed in all patients using quantitative real-time reverse transcription polymerase chain reaction for SARS-CoV-2 RNA. Clinical severity was stratified based on World Health Organization8 guidelines according to clinical, radiographic, and laboratory information from the first 24 h of admission. The primary outcome was days from admission to inhospital mortality. Data for patients who did not meet the primary outcome were censored on April 21, 2020. Our primary analysis explored the causal association between zinc therapy and the survival of hospitalized patients with COVID-19. Inverse probability weighting (IPW) and a censorship model derived an effect estimate of zinc therapy on survival using the parameter defined as the Results Of 242 patients, 81.0% received zinc sulfate at a total daily dose of 440 mg (100 mg elemental zinc). The median age of patients who received zinc was 65 years (interquartile range, 53-77), whereas that of the control 108 Research Letter syndrome-coronavirus-2 (SARS-CoV-2) infection.2-4 Zinc may decrease the activity of the angiotensin converting enzyme 2, the receptor for SARS-CoV-2. Zinc T-cell modulation may downregulate the cytokine storm associated with severe COVID-19.2,4 These properties underlie the speculated efficacy of chloroquine, a zinc ionophore, and the derivative hydroxychloroquine, which are investigational agents in the worldwide World Health Organization SOLIDARITY trial.2,5,6 Furthermore, chloroquine may increase cellular zinc uptake, suggesting therapeutic benefit from the combination of the two agents.4 Despite zinc’s low risk of adverse effects, zinc’s role in the management of COVID-19 must be supported by clinical data.7 Therefore, we investigated the role of zinc among hospitalized patients with COVID-19. average treatment effect on the treated (ATET). The lack of sufficient overlap or the positive probability of assignment to each treatment level precluded the estimation of the average treatment effect. Multivariable logistic regression modeled the propensity to receive zinc by assigning weights to established predictors of mortality and..