Antibacterials for Viral Respiratory Infections: Results of a Physician-Based Intervention in a Predominantly Preferred Provider Organization Setting

Aim: To determine the effectiveness of a multi-component managed-care intervention in reducing inappropriate antibacterial prescribing for viral respiratory infections (VRIs). Study design: An episode-based retrospective analysis of administrative claims data between 1998, the year prior to the initiation of the first component of the intervention, and 2001, the year after full implementation. Patient group studied: All health plan members of the Hawaii Medical Service Association (Blue Cross Blue Shield Hawaii) in the US who sought care for an upper respiratory infection. Methods: To ensure that changes in the rate of antibacterial prescriptions were not because of viral-related infections being coded as bacterial, we measured, in parallel, diagnoses of similar bacterial respiratory infections. Persons with chronic bronchitis, emphysema, and asthma were excluded. Episodes temporally associated with any diagnosis for a non-respiratory bacterial infection were also excluded. Main outcomes: The main study outcome was change in VRI-associated antibacterial utilization. Secondary outcomes included episode-related outpatient, emergency department and inpatient utilization, and estimated cost savings related to changes in antibacterial prescribing rates. Results: The population-based rate of antibacterial use for VRIs decreased significantly between 1998 and 2001, from 39.9% to 33.5%. There was no observed increase in the proportion of bacterial to viral episodes over the same period of time, suggesting that the observed decrease in rates was not a result of coding changes. This reduction in antibacterial prescribing for VRIs was not associated with an increase in emergency department or inpatient utilization. A reduction in VRI-related outpatient visits was observed. The reduction in inappropriate antibacterial prescriptions was estimated to result in a cost saving of approximately $US500 Conclusions: While this study did not offer evidence that one component of the intervention was effective by itself, the combination of all components was associated with decreased antibacterial prescribing for VRIs. The observed reduction in antibacterial prescribing for viral episodes was not associated with increased healthcare visit utilization, and is estimated to be associated with a sizable cost saving. While further research is recommended, this study offers preliminary evidence that multi-component physician feedback programs may be effective in reducing the inappropriate prescribing of antibacterials, and managed care organizations can use claims-based, episode-defined analyses to evaluate the effectiveness of their initiatives.