Decision support during electronic prescription to stem antibiotic overuse for acute respiratory infections: a long-term, quasi-experimental study

BACKGROUND Interventions to support decision-making can reduce inappropriate antibiotic use for acute respiratory infections (ARI), but they may not be sustainable. The objective of the study is to evaluate the long-term effectiveness of a clinical decision-support system (CDSS) interposed at the time of electronic (e-) prescriptions for selected antibiotics. METHODS This is a retrospective, observational intervention study, conducted within a large, statewide Veterans Affairs health system. Participants are outpatients with an initial visit for ARI. A CDSS was deployed upon e-prescription of selected antibiotics during the study period. From 01/2004 to 05/2006 (pre-withdrawal period), the CDSS targeted azithromycin and the fluoroquinolone gatifloxacin. From 05/2006 to 12/2011 (post-withdrawal period), the CDSS was retained for azithromycin but withdrawn for the fluoroquinolone. A manual record review was conducted to determine concordance of antibiotic prescription with ARI treatment guidelines. RESULTS Of 1131 included ARI visits, 380 (33.6%) were guideline-concordant. For azithromycin, concordance did not change between the pre- and post-withdrawal periods, and adjusted odds of concordance was 8.8 for the full study period, compared to unrestricted antibiotics. For fluoroquinolones, guideline concordance decreased from 88.6% (39 of 44 visits) to 51.3% (59 of 115 visits), pre- vs. post-withdrawal periods (p < 0.005). The adjusted odds of concordance compared to "All Other Antibiotics" visits decreased from 24.4 (95% CI 9.0-66.3) pre-withdrawal to 5.5 (95% CI 3.5-8.8) post-withdrawal (p = .008). Concordance did not change between those same time periods for antibiotics that were never subjected to the intervention ("All Other Antibiotics"). CONCLUSIONS A CDSS interposed at the time of e-prescription of selected antibiotics can shift their use toward ARI treatment guidelines, and this effect can be maintained over the long term as long as the CDSS remains in place. Removal of the CDSS after 3.5 years of implementation resulted in a rise in guideline-discordant antibiotic use.