RABBIT Risk Scores are Higher in ICU-Admitted RA Patients Save

The German Rheumatoid Arthritis Biologics Registry (RABBIT) has developed an infectious risk calculator that can project a patient's risk of serious infection in the next 6 months based on several key factors - age, Prior DMARDs, prednisone dose, comorbidities and the biologic intended for use.  (This can be found at http://www.biologika-register.de) 

Others have used this formula to study whether RA patients admitted to an intensive care unit (ICU) for infection would have higher RABBIT risk scores compared to control RA patients.  They identified 74 RA patients with an infectious ICU admission and compared these to 74 frequency-matched control RA patients.

RABBIT risk scores were significantly higher in ICU RA patients (median 2.0; IQR 1.3-3.2) as compared to controls (1.3; IQR 0.8-2.0; p < 0.0001).  RA patients admitted to the ICU for infection were also more likely to be on DMARDs (82.4 vs 64.9%; p = 0.015), biologics (28.4 vs 14.9%; p = 0.012) and steroids (51.4 vs 31.1%; p = 0.012); suggesting those patients also had more active RA.

In a multivariable analysis conventional DMARD use was associated with lower (OR 0.38) and glucocorticoids with borderline higher odds of ICU admission (OR 2.05).

Chronic obstructive pulmonary disease (OR 2.89), chronic kidney disease (OR 16.08), and age (OR 2.67) were alson strongly associated with ICU admission.

Increasing RABBIT risk scores was associated with a strong trend towards higher odds of ICU admission for infection.