Mortality and long term survival prognostic factors of patients with systemic autoimmune diseases admitted to an intensive care unit: a retrospective study.

OBJECTIVES

To determine mortality and long-term survival factors in patients with systemic autoimmune diseases (SAD) admitted to the intensive care unit (ICU).

METHODS

Retrospective observational study including all consecutive patients with a diagnosis of any systemic autoimmune disease admitted to the medical ICU in a tertiary hospital between 1999 and 2007. Factors associated with reduced survival were identified by means of log rank test and backward stepwise Cox regression.

RESULTS

Thirty-seven patients (26 females) were included with median age being 44.3 years (interquartilic range [IQR]: 31.3). Sixteen (43.2%) patients had systemic lupus erythematosus, 9 (24.3%) had systemic vasculitis, 4 (10.8%) had systemic sclerosis and 4 (10.8%) had primary antiphospholipid syndrome. The main reason for ICU admission was autoimmune disease flare-up in 20 (54.0%) patients, followed by infections in 12 (32.4%). Median APACHE II at admission was 17 (IQR 7). At the end of follow-up, 15 (40.5%) patients died, 10 (27%) during hospitalisation (7 in the ICU) and 5 after hospital discharge. Factors associated with reduced long-term survival were: APACHE II score ≥18 (HR 6.02, 95% CI 1.76-20.62), age <45 years (HR 6.54, 95% CI 1.84-23.29), presence of any previous chronic disease (HR 18.20, 95% CI 3.72-88.96), and increase of corticosteroid therapy during ICU stay (HR 22.87, 95% CI 4.31-121.30).

CONCLUSIONS

The long-term survival of patients with systemic autoimmune diseases admitted to the ICU was related with age, higher APACHE II score, previous chronic diseases, and an increase in corticosteroids dose when comparing with previous ICU admissions.