Five versus seven days of nitrofurantoin for urinary tract infections in women with diabetes: a retrospective cohort study

Objective: To compare the effectiveness of 5 versus 7 days of nitrofurantoin treatment for urinary tract infection (UTI) in women with diabetes. Methods: Data were collected retrospectively from Dutch general practitioners between 2013 and 2020. Nitrofurantoin prescriptions with a duration of 5 days (5DN) or 7 days (7DN) in women with diabetes were included. Inverse propensity weighting was performed to calculate adjusted risk differences (RD) for treatment failure within 28 days. Secondary outcomes were 14-day treatment failure, severe treatment failure and 28-day treatment failure in defined risk groups. Results: Nitrofurantoin was prescribed in 6866 episodes, 3247 (47.3%) episodes with 5DN and 3619 (52.7%) episodes with 7DN. Patients in the 7DN group had more co-morbidities, more diabetes-related complications and were more insulin-dependent. There were 517/3247 (15.9%) failures in the 5DN group versus 520/3619 (14.4%) in the 7DN group. The adjusted RD for failure within 28 days was 1.4% (95% CI –0.6 to 3.4). Conclusion: We found no clinically significant difference in treatment failure in women with diabetes with UTI treated with either 5DN or 7DN within 28 days. A 5-day treatment should be considered to reduce cumulative nitrofurantoin exposure in DM patients.