An economic and outcomes assessment of first-line monotherapy in the treatment of community-acquired pneumonia within managed care.

OBJECTIVE: To evaluate the resource consumption and outcomes associated with first-line monotherapy for community-acquired pneumonia, focusing specifically on the use of erythromycin, azithromycin, clarithromycin, and levofloxacin.

STUDY DESIGN: Retrospective managed care database analysis.

PATIENTS AND METHODS: Subjects included patients within a managed care setting over 18 years of age with an initial diagnosis of community-acquired pneumonia from January 1995 to April 2002. Multivariate linear and logistic regression models were used to examine associations with treatment success rates and direct medical costs between antibiotic treatments after controlling for patient demographics and pneumonia risk factors.

MAIN RESULTS: Overall, treatment success rates were high (95.8%), the use of second antibiotics was un common (2.3%), and hospitalizations were infrequent (2.0%) among the 1952 subjects studied. After controlling for patient characteristics and risk factors, significantly lower total costs were associated with erythromycin (92.7% lower, p < 0.001), azithromycin (48.7% lower, p < 0.001), and clarithromycin (21.3% lower, p = 0.015) relative to levofloxacin, with no difference in treatment success between groups. Among newer agents, azithromycin (49.2% lower, p < 0.001) and clarithromycin (21.7% lower, p = 0.013) treatment groups were associated with significantly lower total costs than levofloxacin in the full sample. However, in subjects with a chronic disease score above the sample's mean, only azithromycin was associated with significantly lower total costs (47.9% lower, p < 0.001) relative to levofloxacin.

CONCLUSION: Erythromycin, azithromycin, and clarithromycin were associated with significantly lower total costs than levofloxacin, although treatment success rates did not differ between groups. Following stratification based upon various subset criteria, erythromycin and azithromycin were observed to have significantly lower total costs than levofloxacin. Although these findings may augment clinical guidelines and evidence-based approaches, health plans should consider evaluating their own patient data to see if similar differences exist in their populations.