Antibiotic prescribing for acute, non-complicated infections in primary care in Germany: baseline assessment in the cluster randomized trial ARena.

Background: Antimicrobial resistance is fueled by inappropriate use of antibiotics. Global and national strategies support rational use of antibiotics to retain treatment options and reduce resistance. In Germany, the ARena project (Sustainable reduction of antibiotic-induced antimicrobial resistance) intended to promote rational use of antibiotics for acute non-complicated infections by addressing network-affiliated physicians, primary care teams and patients through multiple interacting interventions. The present study documented patterns of antibiotic prescribing for patients with acute non-complicated infections who consulted a physician in these networks at the start of the ARena project. It explored variation across subgroups of patients and draws comparisons to prescribing patterns of non-targeted physicians.

Methods: This retrospective cross-sectional analysis used mixed logistic regression models to explore factors associated with the primary outcome, which was the percentage of patient cases with acute non-complicated respiratory tract infections consulting primary care practices who were treated with antibiotics. Secondary outcomes concerned the prescribing of different types of antibiotics. Descriptive methods were used to summarize the data referring to targeted physicians in primary care networks, non-targeted physicians (reference group), and patient subgroups.

Results: Overall, antibiotic prescribing rates were 32.0% in primary care networks and 31.7% in the reference group. General practitioners prescribed antibiotics more frequently than other medical specialist groups (otolaryngologists vs. General practitioners OR = 0.465 CI = [0.302; 0.719], p < 0.001, pediatricians vs. General practitioners: OR = 0.369 CI = [0.135; 1.011], p = 0.053). Quinolone prescribing rates were 9.9% in primary care networks and 8.1% in reference group. Patients with comorbidities had a higher likelihood of receiving an antibiotic and quinolone prescription and were less likely to receive a guideline-recommended substance. Younger patients were less likely to receive antibiotics (OR = 0.771 CI = [0.636; 0.933], p = 0.008). Female gender was more likely to receive an antibiotic prescription (OR = 1.293 CI = [1.201, 1.392], p < 0.001).

Conclusion: This study provided an overview of observed antibiotic prescribing for acute non-complicated respiratory tract infections in German primary care at the start of the ARena project. Findings indicate potential for improvement and will serve as comparator for the post-interventional outcome evaluation to facilitate describing of potential changes.