Daily defined dose-costs have a stronger influence on antibacterial drug prescriptions in Germany than bacterial resistance: economic factors are more important than scientific evidence.

Previous research from our group revealed a strong association between daily defined dose (DDD)-costs and -prescriptions of antibacterial drugs in Germany ( https://pubmed.ncbi.nlm.nih.gov/38842562/ ; https://pubmed.ncbi.nlm.nih.gov/39042156/ ). These data indicate that low costs are major driver of high prescription numbers. This study examines the relationship between bacterial resistance and DDD-prescriptions of antibacterial drugs using data from the Arzneiverordnungsreport (AVR) from 2008 to 2022 and the Antibiotic Resistance Surveillance (ARS) statistics provided by the Robert Koch Institute (RKI). We hypothesized that semi-rational or irrational prescribing behavior of antibacterial drugs is evident in Germany, i.e., prescriptions are driven to a greater extents by low DDD-costs than bacterial resistance. A bivariate correlation analysis was performed to test these models. Our data point to irrational prescribing behavior for amoxicillin, cefuroxime axetil, doxycycline, nitrofurantoin, ciprofloxacin, and clarithromycin. For amoxicillin clavulanic acid and sulfamethoxazole-trimethoprim, data point to semi-rational prescribing. For no antibacterial drug, a model pointing to rational drug prescribing was found. In conclusion, our study shows that DDD-costs exert a more significant influence on DDD-prescriptions than bacterial resistance, indicating that economic factors, rather than scientific evidence, primarily drive antibacterial drug prescriptions in outpatient settings in Germany. It will be important to conduct similar studies on the prescription of antibacterial drugs in other countries. It will also be important to study the relation between DDD-costs and -prescriptions for other drug classes and assess the scientific basis for these relations.