Clinical and Laboratory Predictors of Mortality in Hospitalized COVID-19 Patients

Coronavirus disease 2019 (COVID-19) caused by severeacute respiratory syndrome coronavirus 2(SARS-CoV-2) has a variety of symptoms and laboratory and radiologic features whose identification can help diagnose and manage patients with COVID-19 more effectively.

This study aimed to describe the epidemiological, clinical, and laboratory features of patients with COVID-19, compare clinical features of patients in the intensive care unit (ICU) with those of non-ICU admitted patients, and define mortality risk factors for this disease.

This cross-sectional study was carried out on 781 COVID-19 patients hospitalized in Rasool Akram Medical Complex, Tehran, Iran, from February to May 2020. Patients’ epidemiological, demographic, clinical, laboratory findings were collected. Routine blood tests included complete blood count, coagulation profile, and serum biochemical tests. Confirmed infection was defined as positive reverse transcription-polymerase chain reaction (RT-PCR) to SARS-CoV-2 in their nasopharyngeal specimens or typical clinical, laboratory, and imaging findings of COVID-19 infection altogether. All data were analyzed using SPSS software (version 21).

In this study, the majority of patients were male (n=470, 60.2%) and the remainder were female. The median age of the patients was 64 years. Hypertension (31.8%) and tuberculosis (1.4%) were the most common and the least common underlying condition among the patients, respectively. Moreover, cough and seizure were the most common (75.7%)and the least common (2.4%) symptoms in patients. The history of diabetes mellitus, the presence of dyspnea, loss of taste, and the occurrence of seizure were associated with a higher risk of ICU admission. On the other hand, advanced age, positive PCR, presence of dyspnea, myalgia, loss of taste, and elevated liver enzymes, and lactate dehydrogenase (LDH) were associated with a higher risk of mortality. Based on the results, smoking had apreventive effect on mortality (OR=0.292, P=0.048); however, it hadno significant effect on ICU admission.

According to the obtained results, positive PCR and initial symptoms of dyspnea and myalgia were associated with increased odds of mortality by two times. In addition, elevated alanine aminotransferase and lactate dehydrogenase were associated with a higher rate of mortality. ICU admission was the main variable to increase the odds of mortality. Eventually, smoking might play a protective role against COVID-19 mortality.