Results
Study population consists of 123 adults aged 19-87 years, who received diagnosis of COVID-19 pneumonia in a state hospital in Istanbul, Turkey. Among study population 34 (27.6%) subjects had mild pneumonia whereas 89 (72.4%) had severe pneumonia. The number of patients vaccinated with BCG was 91 (74.0%). Sociodemographic, smoke-related, and comorbidities of subjects are summarized in Table 1. Comparison of characteristics of BCG-vaccinated and -unvaccinated COVID-19 pneumonia patients revealed that, mean age and low income rate were significantly higher in BCG-unvaccinated subjects compared to BCG-vaccinated subjects. Severe disease rate was significantly higher in BCG-unvaccinated subjects compared to BCG-vaccinated subjects (87.5% vs 67.0%; p=0.026) (Table 2). Mean age, rate of diabetes, low-income and BCG-vaccination status were the parameters differed significantly between mild and severe COVID-19 pneumonia patients (Table 3). Effects of age, gender, income, BCG-vaccination status, diabetes and hypertension on the likelihood of severe COVID-19 pneumonia were assessed with logistic regression. The logistic regression model is statistically significant, χ2(8) = 7.072, p =.529 and it explains 46.0% (Nagelkerke R2) of the variance severe disease and correctly classifies 84.6% of cases. The analysis revealed that increased age and low-income independently predict severe disease among COVID-19 pneumonia patients. On the contrary, BCG-vaccination status is not associated with severity of COVID-19 pneumonia (Table 4).