Characteristics and outcome of critically ill patients with systemic rheumatic diseases referred to the intensive care unit

Abstract

Objectives: Patients with systemic rheumatic diseases (SRDs) are at risk of admission to the intensive care unit (ICU). Data concerning these critically ill patients are limited to few retrospective studies.

Methods: This is a single-centre retrospective study of patients with SRDs admitted to an ICU at the Vienna General Hospital between 2012 and 2020. Single-predictor and multiple logistic regression analysis was performed to identify potential outcome determinants.

Results: A total of 144 patients accounting for 192 ICU admissions were included. Connective tissue diseases (CTDs), vasculitides and rheumatoid arthritis were the most common SRDs requiring ICU admission. Leading causes for ICU admission were respiratory failure and shock, as reflected by a high number of patients requiring mechanical ventilation (60.4%) and vasopressor therapy (72.9%). Overall, 29.2% of admissions were due to SRD-related critical illness. In 70.8% patients, co-existent SRD not responsible for the acute critical illness was documented. When comparing these subgroups, CTDs and vasculitides had a higher frequency in the patients with SRD-related critical illness. In a significantly higher proportion of patients in the SRD-related subgroup, diagnosis of SRD was made at the ICU. ICU and 6-month mortality in the overall population was 20.3% and 38.5%, respectively. Age, glucocorticoid therapy prior to hospital admission and disease severity were associated with poor outcome.

Conclusions: In this study, respiratory failure was the leading cause of ICU admission as reflected by high rates of required mechanical ventilation. Despite considerable severity of critical illness, survival rates were comparable to a general ICU population.

Keywords: autoimmune diseases; cardiovascular diseases; epidemiology; immune system diseases; inflammation.