Prediction of lethal outcomes in COVID-19 cases based on the results chest computed tomography

The objective: to predict lethal outcomes in patients with COVID-19 based on the result of chest computed tomography (chest CT) using a semi-quantitative visual scale of the pulmonary parenchyma lesion.Subjects and methods. Inclusion criteria: patients who underwent chest CT from March 2 to May 1, 2020, inclusively, upon referral of a general practitioner due to suspected community-acquired pneumonia caused by COVID-19. Chest CT was performed in 48 medical organizations providing primary medical care to the adult population in Moscow. Exclusion criteria: patients whose chest CT was not assessed by CT 0-4 score; patients who were not confirmed as COVID-19 positive.In the Russian Federation, CT 0-4 score is recommended to be used for assessment of the extent of lung parenchyma lesion in cases with suspected COVID-19.Data on fatal outcomes were received on May 4, 2020 inclusive.Results: data of 13,003 patients from the Unified Radiological Information Service were retrospectively included in the study according to inclusion and exclusion criteria. The test aimed to detect a trend of directional changes in the proportion of deceased patients among various categories using CT 0-4 score demonstrated a statistically significant result (p < 0.0001). The chance of a lethal outcome increases directionally from CT-0 to CT-4. The test for deviations from the linear trend also provided p < 0.0001, i.e. when moving to higher scores (CT-3 and CT-4), there was an accelerated increase in the risk of death. Analysis of overall survival using the Cox regression model showed that the assessed factors (age and CT 0-4 score) were statistically significantly associated with the time to death from COVID-19 (p < 0.05). The risk of death increased with age, on average, 8.6% for every 5 years (95% CI 0.8-17.0%). When transferring from one category of CT to the next one, the risk increased by 38% on the average (95% CI 17.1-62.6%). There was no statistically significant association of gender factor with overall survival (p = 0.408).The visual score of CT 0-4 recommended for use in the Russian Federation to assess lung parenchyma lesions according to chest CT data, is a predictor of a lethal outcome in patients with COVID-19. CT 0-4 score is convenient for practical use.