Association Between rRT-PCR Test Results Upon Admission and Outcome in Hospitalized Chest CT-Positive COVID-19 Patients: A Provincial Retrospective Cohort with Active Follow-up

Background: The coronavirus disease 2019 (COVID-19) pandemic imposed the most devastating challenge on healthcare systems worldwide. Iran was among the first countries that had to confront serious shortages in reverse-transcriptase-polymerase chain reaction (RT-PCR) testing for severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) and ventilators availabilities throughout the COVID-19 outbreak. Objectives: This study aimed to investigate the clinical course of hospitalized COVID-19 patients with different real-time RT-PCR test results during the first three weeks of the outbreak in Qazvin province, Iran. Methods: In this retrospective cohort study, patients with a positive chest computed tomography (CT) scan for COVID-19 who were admitted to all 12 hospitals across Qazvin province, Iran, between February 20 and March 11, 2020, were included and followed up until March 27, 2020. A multivariate logistic regression model was applied to compare the independent associates of death among COVID-19 patients. Then, patients were categorized into six groups based on admission to the intensive care unit (ICU) and rRT-PCR test status (positive, negative, or no test). Also, multilevel logistic regression was used to compare the odds of surviving in each group against the reference group (PCR negative patients not-received ICU) to show if the rational allocation of ICU occurred while its capacity is limited. Results: In this study, we included 998 patients (57% male; median age: 54 years) with positive chest CT scan changes. Among them, 558 patients were examined with rRT-PCR test and 73.8% tested positive. Case fatality rate (CFR) was 20.68 and 7.53% among hospitalized patients with positive and negative tests, respectively. While only 5.2% of patients were admitted to the ICU, CFR outside ICU was 17.70 and 4.65% in patients with positive and negative results not admitted to the ICU, respectively. Conclusions: Total CFR in all hospitalized COVID-19 patients in Qazvin province during the first three weeks of the pandemic was 11.7%. Also, according to the results, the main risk factors included a positive rRT-PCR test, age more than 70 years, and having two or more comorbidities or just immunodeficiency disorders. Hence, the ICU admission criteria or prioritized ICU beds allocation should be considered with more emphasis on rRT-PCR results when the capacity of ICU beds is low.