Office-Related Antibiotic Prescribing for Medicaid-Enrolled Children

BACKGROUND: Prudent antibiotic prescribing is essential to limiting antibiotic resistance. Thus far, minimal resources have been devoted towards ensuring appropriate antibiotic prescribing in Montana. We aimed to assess the trend in percentage of clinician office visits for acute respiratory infections (ARIs) linked with an antibiotic prescription. ARIs are most frequently caused by viral infections and often not effectively treated with antibiotics.

METHODS: We performed a retrospective analysis of Medicaid billing claims data for each year during 1999–2010. Study subjects included children aged ≤14 years who were continuously enrolled in Montana Medicaid. All office visits were identified for each subject. An index office visit was defined as the first visit during any 10-day period. Only the primary diagnostic code associated with the index visit was used for analysis. Primary outcomes were ARI-related (otitis media, bronchitis, pharyngitis, sinusitis, and non-specific upper respiratory infection [common cold]) office visits and filled antibiotic prescriptions within 10 days of office visit. Logistic models were fitted to the data to assess for trend in the percentage of office visits linked with a filled antibiotic prescription over time using year of visit as the predictor variable. Separate logistic models were fit for all ARI diagnoses combined, and for each ARI diagnosis.

RESULTS: Over 372,000 children-years of Montana Medicaid enrollment and 873,244 index office visits were identified. Nearly 117,000 (13%) index visits had an ARI as primary diagnosis. Of these, diagnoses included otitis media (n = 50,770 [43%]), common cold (37,571 [32%]), pharyngitis (13,961 [12%]), bronchitis (7,399 [7%]), and sinusitis (7,261 [6%]). Among ARI-related office visits, 64,250 (55%) were linked with an antibiotic prescription. From 1999 to 2010, no change occurred for the odds of ARI-related office visits being linked with an antibiotic prescription (odds ratio [OR] = 1.00, 95% confidence interval [CI] = 0.995–1.002), a slight increase occurred for otitis media (1.03, 1.023–1.034) and bronchitis (1.04, 1.026–1.056), and a slight decrease occurred for pharyngitis (0.97, 0.963–0.982) and the common cold (0.97, 0.962–0.974). A non-statistically significant increase occurred for sinusitis (OR = 1.02, 95% CI = 1.000–1.034).  

CONCLUSIONS: ARI-related outpatient visits were often linked with antibiotic prescriptions among Montana Medicaid-enrolled children. The percentage of total ARI-related visits linked with an antibiotic prescription did not decrease from 1999 to 2010. Further prevention efforts aimed at improved antibiotic prescribing practices in Montana are needed to reduce the use of antibiotics for treatment of ARIs.