Quality of antibiotic prescribing for outpatient cystitis in adult females

Background: Urinary tract infections (UTI) are responsible for a significant portion of female, outpatient antibiotic prescriptions. Especially true in uncomplicated cases, where symptoms remain the cornerstone of diagnosis, ensuring the optimal choice of agent, dose, and duration may mitigate future bacterial resistance and lower the likelihood of adverse events and/or recurrence. This study is the first in Canada to examine the quality of antibiotic prescribing to females in the outpatient setting, for uncomplicated UTI–by agent, dose, and duration. Methods: All adult female residents of British Columbia with a physician record for cystitis from January 1, 2014, to December 31, 2018, were identified. Patients with a history of urologic abnormalities, spinal cord injury, catheter use, kidney transplant, as well as pregnant females, were excluded. Primary outcomes included the proportion of total episodes prescribed and the proportion of appropriate antibiotic use, examined using Poisson regression. Results: A total of 182,162 episodes of cystitis were examined, with 70% receiving an antibiotic prescription. The rate of cystitis-associated prescribing was 697 prescriptions per 1,000 population. Overall, 35% of prescriptions were appropriate by guideline adherence or clinical justification. Nitrofurantoin and trimethoprim-sulfamethoxazole, accounted for 71% of total antibiotic use. Seven days was the most commonly dispensed duration of therapy, followed by 5, then 10. Conclusions: Shortening length of therapy in line with clinical guidelines and encouraging the use of first line agents present clear, actionable targets for provincial stewardship efforts.