Evaluation and treatment of respiratory infections: does managed care make a difference?

Primary care physicians frequently use antibiotics for nonindicated conditions and conditions for which antibiotics have not been shown to be effective. The intention of this study was to determine whether shifting the costs from the insurer to physicians in a staff model health maintenance organization (HMO) influenced antibiotic prescribing.

A random sample of patients in whom upper respiratory infections (URIs) (n = 334) or acute bronchitis (n = 218) were diagnosed within a 12-month period was selected from a large multispecialty group practice whose population was predominantly fee-for-service (FFS) and from a staff model HMO. Detailed chart reviews were performed to verify the diagnosis and note secondary diagnoses, identify whether an antibiotic or other medication was prescribed, assess whether diagnostic testing was performed, and determine the specialty of the clinician.

After excluding patients seen with sinusitis, otitis media, or streptococcal pharyngitis, 334 patients with URIs and 218 patients with acute bronchitis remained for analysis. For URIs, antibiotic prescribing was higher in the HMO population than in the FFS group (31% vs 20%, P = .02). In patients with acute bronchitis, HMO patients were also more likely to have an antibiotic prescribed, but the difference was not statistically significant (82% vs 73%, P = .11). Further analyses showed that while HMO physicians were more likely to prescribe antibiotics, they were less likely to prescribe other medications for acute bronchitis or use diagnostic tests for evaluation of patients with URIs or bronchitis.

Shifting costs from insurer to physicians through managed care appears to reduce diagnostic testing for URIs and acute bronchitis, but does not decrease excessive use of antibiotics and may actually increase antibiotic use for URIs.