Identification of clinical and demographic variables associated with severe Covid-19 in subjects with rheumatic disease in a third-level hospital in Mexico City

ABSTRACT

Dear editor Subjects with rheumatic diseases are a group with risk for clinical complications by Covid-19.1 Some demographic and clinical variables have been identified as risk factors for severe Covid-19 in infected people, but is not clear whether these predictors might further increase risk in patients with rheumatic diseases.2 In this retrospective study based on a systematic sampling from May 2020 to July 2021, we assessed severity-associated risk generated by Covid-19 between a group of patients with rheumatic diseases (54.5%, n=36, RDs group) and another group without immunological deterioration (45.4%, n=30, NRs patients) (Protocol Register Number 09-CEI-005-20201111). Clinical and demographic data from sixty-six patients with Covid-19 confirmed by PCR testing and computed tomography for lung lesions were collected (table I). Severity in patients were classified based on oxygen requirement levels since non-severe condition (PaO2 /FiO2 >95%) or any other condition according with the World Health Organization criteria.3 Results showed that 11.1% of RDs patients required mechanical ventilation, 47.2% required any oxygen supplement and 41.7% were classified as non-severe Covid-19 while all non-rheumatic cohort required any minor oxygen support. Analysis by logistic regression models identified that the risk for clinical complications such as acute respiratory distress syndrome (ARDS) were associated with the presence of diabetes mellitus type-2 (DMT-2) (OR 5.61 [1.7747,17.7367], p-value<0.05). Particularly, in RDs group the risk for severe Covid-19 were associated with the presence of DMT-2 (OR 21.00 [1.7343,254.274], p<0.05), which was nine times higher than in NRs group. Our data are similar with reports in where presence of comorbidities are associated with hospitalization due to severe Covid-19.4 Moreover, clinical parameters were associated to severe Covid-19 in RDs group including creatinine >1.5 mg/ dL (OR 1.6875 [0.3043,9.3584], p<0.05);alanine aminotransferase enzyme ≥40 U/L (OR 9.000 [1.1257,71.9578], p<0.05), lymphocytes counts <1000 per mL (OR 13.50 [1.3793,1315789], p<0.05) and hemoglobin <10 g/dL (OR 18.75 [1.5434,227.7808], p<0.05). These increases in risk could be explained by immunological disfunction own of each rheumatic disease or by genetic variants of the adaptive and innate immune system.5 In this study, we concluded that individuals with rheumatic disease have an increased risk for very severe Covid-19 and non-rheumatic predictors may affect them even more than general population. © 2023,Salud Publica de Mexico. All rights reserved.