Effect of national antimicrobial resistance policies on antibiotic prescribing rates in South Korea: an interrupted time series analysis.

backgroundDespite the antimicrobial resistance (AMR) policies implemented in Korea, outpatient antibiotic consumption remains high. Evidence on the effects of these policies is limited. We assessed the effects of Korea's AMR control policies on antibiotic prescription rates by examining short- and long-term impacts across healthcare institution types and policy intervention periods.

methodsWe conducted an interrupted time series analysis using an ARIMAX (1,0,0) model with nationwide quarterly data from tertiary hospitals, general hospitals, hospitals, and clinics from the first quarter of 2000 to the fourth quarter of 2023. Four policy interventions were modeled as level and slope changes to estimate short-term effects immediately after each intervention and long-term effects eight quarters later.

resultsThe 2001 policy was associated with short-term reductions in antibiotic prescription rates across all institution types, decreasing by 2.21% points (pp) in tertiary hospitals, 3.65 pp in general hospitals, 1.60 pp in hospitals, and 3.21 pp in clinics. Long term, reductions were observed only in general hospitals (- 2.95 pp), while increases occurred in other settings. Following the 2006 policy, short-term prescription rates increased across all institutions but declined in the long term in tertiary (- 2.94 pp) and general hospitals (- 2.61 pp), with increases persisting in hospitals and clinics. After the 2013 policy, short-and long-term prescription rates increased across all institution types. The 2017 policy was associated with short-term increases across all settings, long-term decline was observed only in clinics (- 0.94 pp).

conclusionThe effects of Korea's AMR policies varied according to policy type, implementation period, and healthcare institution type, with substantial differences between short-term and long-term outcomes. Although several policies were associated with reductions in antibiotic prescribing, these effects were often not sustained over time. These findings suggest that regulation, public reporting, and financial incentives alone are insufficient to achieve lasting changes in prescribing behavior. Sustainable AMR control will require institution-specific and multifaceted strategies that integrate antimicrobial stewardship, continuous monitoring and feedback, patient engagement, and One Health approaches.