Interrupted Time-Series Analysis to Evaluate the Impact of a National Antimicrobial Stewardship Campaign on Antibiotic Prescribing: A Typical Practice in China's Primary Care.

BACKGROUND: After implementing the 2011 national antimicrobial stewardship campaign, few studies focused on evaluating its effect in China's primary care facilities.

METHODS: We randomly selected 11 community health centers in Shenzhen, China, and collected all outpatient prescriptions of these centers from 2010-2015. To evaluate the impact of local interventions on antibiotic prescribing, we used a segmented regression model of interrupted time series to analyze seven outcomes, i.e., percentage of prescriptions with antibiotics, and percentages of prescriptions with broad-spectrum antibiotics, with parenteral antibiotics, and with two or more antibiotics in all prescriptions or antibiotics-containing prescriptions.

RESULTS: Overall, 1 482 223 outpatient prescriptions were obtained. The intervention was associated with a significant immediate change (-5.2%, P=.04) and change in slope (-3.1% per month, P<.01) for the percentage of prescriptions with antibiotics, and its relative cumulative effect at the end of the study was -74.0% (95% confidence interval, -79.0% to -69.1%). After the intervention, the percentage of prescriptions with broad-spectrum, and with parenteral antibiotics decreased dramatically by 36.7% and 77.3%, respectively, but their percentages in antibiotic-containing prescriptions decreased insignificantly. Percentage of prescriptions with two or more antibiotics in all prescriptions or antibiotics-containing prescriptions only showed immediate changes, but significant changes in slope were not observed.

CONCLUSIONS: A typical practice in Shenzhen, China, showed that strict enforcement of antimicrobial stewardship campaign could effectively reduce antibiotic prescribing in primary care with a stable long-term effect. However, prescribing of broad-spectrum and parenteral antibiotics was still prevalent. More targeted interventions are required to promote appropriate antibiotic use.