Efficacy of antibiotic prophylaxis among intermittent catheter users with different neurologic diseases: A secondary analysis of the AnTIC Trial

Objective: To use existing clinical trial data to assess the impact of prophylactic antibiotics on the 1-year UTI rate among people with different neurologic diseases, and to determine if UTIs impact renal function. Methods: We conducted a secondary analysis of community dwelling participants with a neurologic disease and intermittent catheter use who participated in a 12-month randomized trial (AnTIC) of low dose antibiotic prophylaxis. We calculated incident rate ratios (IRR) of symptomatic UTIs that required antibiotics. Renal function was assessed using the estimated glomerular filtration rate. Results: We identified 138 patients who had a neurologic disease (multiple sclerosis (25%), spinal cord injury (21%), spina bifida (18%), and other disorders (36%)). The incidence of symptomatic, antibiotic treated urinary infections was 1.48 per person–year in the prophylaxis group, and 2.51 per person–year in the usual care group; the IRR was 0.59 (95% CI 0.46, 0.76) in favor of continuous antibiotic prophylaxis. The IRR was lowest (most protective) among those with spinal cord injury (IRR 0.23, p < 0.01) and highest (least protective) in those with spina bifida (IRR 0.85, p = 0.57). There were small, non-significant decreases in renal function that did not differ by randomization. There were no significant differences in pre- and post-study renal function based on the number of UTIs participants experienced. Conclusion: Continuous antibiotic prophylaxis may be more effective for certain patient populations with neurologic lower urinary tract dysfunction. Renal function is not significantly impacted by a higher number of UTIs over the course of one year.