Methods
Study population and data collection
This retrospective cross-sectional
study was conducted in subjects who were diagnosed with COVID-19
pneumonia based on positive SARS-CoV-2 polymerase chain reaction result
in combined nasal-throat swab sample and pulmonary infiltrates in
computed chest tomography in a state hospital in Istanbul, Turkey
between 11 March and 10 June, 2020. Study population was grouped
according to severity of COVID-19 pneumonia according to Turkish
Ministry of Health COVID-19 guide; 1) subjects with severe clinical
condition with tachypnea (≥30 / minute), oxygen saturation below 90%
breathing room air together with bilateral diffuse pulmonary infiltrates
and hospitalized, 2) subjects with mild clinical condition followed up
on an outpatient
basis.5
Sociodemographic characteristics,
body-mass index, smoking history, comorbid diseases, and symptoms were
recorded from the patients’ files. Subjects earning minimum wage
(monthly income approximately less than 355 U.S. dollar) were defined as
low income. BCG vaccination history was determined based on subjects’
self-declaration together with observation of vaccine scar by consultant
pulmonologist.