Risk factors of adverse outcome of COVID-19 and experience of tocilizumab administration in patients on maintenance hemodialysis due to diabetic kidney disease

ABSTRACT

BACKGROUND: Patients with Type 2 Diabetes (T2DM) and patients on maintenance hemodialysis (MHD) are at a high risk of adverse clinical course of COVID-19. To date, the causes of high mortality in these groups are not fully understood. Data about peculiarity of clinical course and Tocilizumab (TCZ) administration in patients with T2DM receiving MHD due to outcome of diabetic kidney disease (DKD) are not yet highlighted in current publications. AIMS: Identification of risk factors (RF) of adverse COVID-19 outcome and evaluation of TCZ administration in patients with T2DM receiving MHD due to DKD. MATERIALS AND METHODS: The patients treated in Moscow City Hospital №52 were included in retrospective observational study. The observation period was from 04.15 to 07.30 2020. The study endpoints were the outcomes of hospitalization - discharge or lethal outcome. Data were collected from electronic medical database. The following independent variables were analysed gender, age, body mass index, time from the onset of symptoms to hospital admission, cardiovascular and general comorbidity (Charlson Index, CCI), cardiovascular event (CVE) during hospitalization, treatment in ICU, mechanical ventilation (MV), degree of lung damage according to CT data, level of prandial glycemia at admission, MHD-associated parameters (vintage, type of vascular access, frequency of complications). The autopsy reports were evaluated for the purpose of lethal structure investigation. In a subgroup treated TCZ the time from symptoms onset to TCZ administration and number of laboratory indicators were evaluated. RESULTS: 53 patients were included, mean age 68 ±9 y, males - 49%. General mortality in observation cohort was 45%, mortality in ICU - 81%, mortality on MV - 95%. High cardiovascular and general comorbidity was revealed (mean CCI - 8,3 ±1,5 points). The causes of outcomes according to autopsy reports data CVE 37,5% (among them - acute myocardial infarction during hospitalization), severe respiratory failure - 62,5%. The independent predictors of lethal outcome were MV (OR 106;95% CI 11,5-984;р <0,001), 3-4 degree of lung damage according to CT data (ОR 6,2;95% CI 1,803-21,449;р = 0,005), CVE during hospitalization (ОR 18,9;95% CI 3,631-98,383;р <0,001);CCI ≥10 points (ОR 4,33;95% CI 1,001-18,767;р = 0,043), level of prandial glycemia at admission ≥10 mmol/l (ОR 10,4;95% CI 2,726-39,802;р <0,001). For risk identification of upcoming lethal outcome a predictive model was created with the use of discovered RF as variables. The predictive value of this model is 92,45% (positive prognostic value - 96,5%, negative prognostic value - 87,5%). In TCZ treated subgroup the laboratory markers of adverse outcome were detected with application of correlation analysis. Among them increasing level of CPR 24-48 hours before lethal outcome (r = 0,82), the reduction of lymphocytes count after TCZ administration (r = -0,49), increasing of leukocytes and further reduction of lymphocytes count 24-48 hours before lethal outcome (r = 0,55 и r = -0,52, resp.)). CONCLUSIONS: The number of RF of adverse COVID-19 outcome in patients with T2DM receiving MHD due to DKD are identified. CVE is one of the leading causes of mortality in study cohort. According to our experience the preventive (instead of rescue) strategy of TCZ administration should be used.