CRP-Guided Prescribing for COPD Exacerbations

Results of a recent study are suggesting that C-reactive protein (CRP) guided antibiotic prescribing for chronic obstructive pulmonary disorder (COPD) exacerbations in primary care clinics could reduce use of antibiotics.

Investigators examined more than 650 patients across England and Wales and determined that CRP-guided prescribing resulted in a lower percentage of patients who reported antibiotic use and who received antibiotic prescriptions from clinicians with no evidence of harm to patients. 



In order to evaluate the impact of point-of-care testing of CRP-guided prescribing could have on antibiotic use, investigators carried out a multicenter, open-label, randomized, controlled trial across 86 clinics in England and Wales. Patients were randomized in a 1:1 ratio to a CRP-guided group or usual care alone.

Before randomizing participants, investigators collected information the number of days that symptoms of acute exacerbation of COPD were present, a patient’s medical history, examination findings from clinicians, a sputum sample, a throat swab, patient responses to the self-administered Clinical COPD Questionnaire, and patients’ responses to the European Quality of Life—5 Dimensions 5-Level questionnaire (EQ-5D-5L).

Investigators followed up with participants via telephone calls at weeks 1 and 2 and an in-person consultation at week 4. At the 6-month mark, investigators mailed a self-administered, standardized version of the Chronic Respiratory Disease Questionnaire and EQ-5D-5L.

Clinicians performed CRP point-of-care test as part of their assessment at the initial consultation and at any other consultations for exacerbations of COPD over the following 4 weeks. The usual care group did not undergo CRP testing.

The primary outcomes of the study were patient-reported antibiotic use for an acute exacerbation in the first 4 weeks and COPD-related health status — as measured by the Clinical COPD Questionnaire 2 weeks after randomization.

For the final analyses, a total of 653 patients were identified for inclusion in the study. Investigators found that fewer patients in the CRP group reported antibiotic use than in the usual care group (57.0% vs. 77.4%; aOR, 0.31; 95% CI, 0.20 to 0.47). The adjusted mean difference between the 2 groups, in terms of total score on the Clinical COPD Questionnaire at 2 weeks, was -0.19 in favor of the CRP group. 



Investigators noted that antibiotic prescribing designs were made by clinicians at the initial consultation, except for 1 patient, and antibiotic prescriptions issued over the first 4 weeks of follow-up were ascertained for most (96.9%) of patients. Lower percentages of patients in the CRP group received an antibiotic prescription at the initial consultation (47.7% vs. 69.7%; aOR, 0.31; 95% CI, 0.21 to 0.45) and during the first 4 weeks (59.1% vs. 79.7%; aOR 0.30; 95% CI, 0.20 to 0.46) than in the usual care group.

In a related editorial, Allan Brett, MD, and Majdi Al-Hasan, MB, both of the University of South Carolina School of Medicine, wrote that the results of the current study should be definitive enough to have a tangible impact on COPD care.

“In our view, the findings from this study are compelling enough to support CRP testing as an adjunctive measure to guide antibiotic use in patients with acute exacerbations of COPD,” Brett and Al-Hasan wrote. 



“Although acute exacerbations of COPD represent only a small fraction of the cases seen in primary care practices, point-of-care CRP testing has also been shown to reduce antibiotic prescribing for more common clinical presentations,” they continued.

This study, titled “C-Reactive Protein Testing to Guide Antibiotic Prescribing for COPD Exacerbations,” is published in the New England Journal of Medicine.