Objective: To undertake a 1-year prospective economic evaluation of ciprofloxacin compared with usual antibacterial care (any antibacterial other than a quinolone) for the treatment of acute exacerbations of chronic bronchitis (AECB) in adults presenting with a type I or type II AECB.
Design: Patients entered the study with an initial AECB and were randomised to the ciprofloxacin group or the usual care group. The following measurements were taken at the end of each AECB and every 3 months: resource utilisation, St. George's Respiratory Questionnaire, Nottingham Health Profile and Health Utilities Index (HUI). The following additional measurements were taken after each AECB: AECB-symptom days and willingness to pay to avoid the AECB. Economic evaluations were performed from the societal viewpoint and the viewpoint of a major third-party payer. Cost-effectiveness analysis was based on cost per AECB-symptom day averted; cost-utility analysis (CUA) was based on cost per quality-adjusted life-year (QALY) gained using the HUI as the basis for calculating QALYs. Cost-benefit analysis was based on the willingness-to-pay (WTP) data.
Setting: This was a study of outpatients enrolled from 46 family physicians and 2 respirologists in Ontario (29 sites) and Québec (19 sites), Canada, between November 1993 and June 1994.
Patients and participants: 240 adult male and female patients aged > or = 18 years with chronic bronchitis.
Main outcome measures and results: WTP data did not pass scope tests for reasonableness. Ciprofloxacin was more costly and provided better outcomes compared with usual antibacterial care. The base-case results are as follows (1994/1995 values): the incremental annual cost was 578 Canadian dollars ($Can) from the societal viewpoint and $Can840 for the third-party payer; the cost-effectiveness ratio per AECB-symptom day averted was $Can209 from the societal viewpoint and $Can304 for the third-party payer; the cost-utility ratio per QALY gained was $Can18,600 from the societal viewpoint and $Can27,000 for the third-party payer. According to Laupacis criteria, these CUA results are strong evidence in favour of adoption from the societal viewpoint and moderate evidence in favour from the viewpoint of the third-party payer. A subgroup analysis suggests that ciprofloxacin may be particularly cost effective, even 'win-win', in patients with more severe disease.
Conclusions: The sensitivity analyses indicate that the results are relatively robust. Nevertheless, the statistical uncertainty in the results is sufficient that the findings cannot be accepted unequivocally. A further study with a larger sample size would be useful to confirm (or deny) the findings of this study.