CURB-65 Tool in Community-Acquired Pneumonia Useful But Has Limitations
Because CURB-65 has a comparatively low sensitivity, it should be used with discretion in clinical predictions.
A score of ≤2 on confusion, uremia, elevated respiratory rate, and hypotension at ≥65 years of age (CURB-65), a clinical prediction rule, has shown an association with intensive care unit (ICU) admittance, according to a study published in Annals of Emergency Medicine. However, CURB-65 has a comparatively low sensitivity and should be used with discretion in clinical predictions.
This study included 2322 individuals with community-acquired pneumonia, 27.1% (n=630) of whom were admitted to the ICU within 2 days of assessment in the emergency department and 14.8% (n=343) of whom underwent a subsequent critical care intervention. Of the individuals with a scored between 0 and 1 on CURB-65, 15.6% (n=181) went to the ICU, 6.4% (n=74) required critical care, and 0.6% (n=7) died. Of those with a score of 2 on CURB-65, 27.0% (n=223) went to the ICU, 15.4% (n=127) required critical care, and 5.7% (n=47) died. Of those with a score ≥3, 67.0% (n=226) were admitted to the ICU, 42.1% (n=142) required critical care intervention, and 12.8% (n=43) died.
The prognostic power of CURB-65 for mortality and critical care intervention as area below the receiver operating characteristic were 0.77 (95% CI, 0.73-0.81) and 0.73 (95% CI, 0.71-0.76), respectively. A CURB-65 score ≥2 had a sensitivity of 78.4% (95% CI, 73.7%-82.7%) in predicting critical care intervention and 92.8% (95% CI, 85.7%-97.0%) in predicting mortality.
This retrospective analysis included electronic health records drawn from a single tertiary center for patients of the emergency department who were diagnosed with pneumonia between 2010 and 2014. Exclusion criteria included previous tuberculosis, bronchiectasis, HIV, malignancy, or being readmitted within 2 weeks. The predictive power of CURB-65 was evaluated for mortality within the hospital and for interventions including vasopressors, invasive catheters, insulin infusions, renal replacement therapy, assisted breathing, and large-volume intravenous fluids. The likelihood of an increase in mortality in the hospital or of critical care intervention coinciding with an increasing score on CURB-65 was assessed using logistic regression.
Study researchers concluded, “Patients with CURB-65 score [≤]2 were often admitted to the ICU and received critical care interventions. Given this finding and the relatively low sensitivity of CURB-65 for critical care intervention, clinicians should exercise caution when using CURB-65 to guide disposition. Future [emergency department] clinical prediction rules may benefit from calibration to proximal end points.”
Ilg A, Moskowitz A, Konanki V, et al. Performance of the CURB-65 Score in predicting critical care interventions in patients admitted with community-acquired pneumonia [published online August 2, 2018]. Ann Emerg Med. doi:10.1016/j.annemergmed.2018.06.017