Cost-effectiveness of C-reactive protein point of care testing for safely reducing antibiotic consumption for acute exacerbations of chronic obstructive pulmonary disease as part of the multicentre, parallel-arm, open, individually randomised, controlled PACE trial

Objectives: Many patients presenting with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) in primary care do not benefit from antibiotics. Excessive use wastes resources, promotes antimicrobial resistance and can harm patients.

Design: We conducted a within-trial economic evaluation, using a UK National Health Service perspective, as part of the multicentre, parallel-arm, open, individually randomised, controlled PACE trial.

Setting: Participating general practices in primary care.

Participants: PACE included 324 and 325 consenting participants presenting with AECOPD in the usual-care and CRP-guided groups, respectively.

Intervention: We assessed the cost-effectiveness (CE) of a C-reactive protein point-of-care-test (CRP-POCT) in addition to usual clinical assessment to guide antibiotic prescribing for AECOPD in primary care.

Primary and secondary outcome measures: A cost-effectiveness analysis (CEA) of incremental cost per 1% antibiotic consumption reduction at 4 weeks and a cost-utility analysis (CUA) at 6 months were performed, based on a modified intention-to-treat population. Sensitivity analyses assessed the impact of uncertainty on the results. CE acceptability curves represent the probability of CRP-POCT being cost-effective at different willingness-to-pay (WTP) thresholds.

Results: Both groups had similar clinical outcomes, but a 20% absolute reduction in antibiotic consumption was observed in the CRP-guided group. CRP-POCT costs of £11.31 per test were largely offset by savings in healthcare resource use related to COPD. The mean incremental CE ratios of CRP-POCT were £120 per 1% absolute reduction in antibiotic consumption at 4 weeks and £1054 per quality-adjusted life-year (QALY) gained at 6 months. Sensitivity analysis showed that the CEA results were most affected by changes in healthcare costs, while CUA was sensitive due to marginal differences in costs and outcomes. There is a 73% probability of CRP-POCT being cost-effective at WTP ≤£20 000 per QALY gained.

Conclusion: CRP-POCT is a cost-effective intervention for safely reducing antibiotic consumption in patients with AECOPD.

Trial registration number: ISRCTN24346473.