Effect of imidafenacin on the urodynamic parameters of patients with indwelling bladder catheters due to spinal cord injury

STUDY DESIGN: A retrospective study. OBJECTIVES: To investigate the effect of imidafenacin on the urodynamic parameters of patients with indwelling bladder catheters due to spinal cord injury (SCI). SETTING: Spinal center (Tokyo, Japan). METHODS: Imidafenacin was prescribed to 34 patients with SCI who had a low cystometric volume and/or detrusor compliance according to a urodynamic study. A low cystometric volume and detrusor compliance were defined as <200 ml and <20 ml cm(−1) H(2)O, respectively. The urodynamic study was repeated 4 weeks after imidafenacin was prescribed. When the urodynamic parameters did not improve in the follow-up study, the dose of imidafenacin was increased twofold. Then the urodynamic study was repeated 4 weeks thereafter. We compared the urodynamic parameters before and after imidafenacin treatment. Complications such as vesico-urethral reflux (VUR) and autonomic dysreflexia (AD) were documented. RESULTS: Fifteen patients took 0.2 mg of imidafenacin daily, and 19 received 0.4 mg of imidafenacin daily. Imidafenacin increased the cystometric volume from 246.0 to 321.5 ml (median, P=0.002), detrusor compliance from 6.67 ml cm(−1) H(2)O to 8.98 ml cm(−1) H(2)O (median, P=0.012), and decreased the detrusor pressure from 37.0 cm H(2)O to 30.5 cm H(2)O (median, P=0.056). All three patients who had VUR fully recovered. Although 3 of 12 patients recovered from AD, 3 patients newly developed symptoms of AD. No patient withdrew from treatment due to adverse effects. CONCLUSION: Imidafenacin is a safe drug that may improve the urodynamic parameters of patients with SCI, and it possibly alleviates bladder complications.