Objectives: Clinical efficacy, influence on quality of life (QOL), and safety of imidafenacin before sleeping were assessed in patients with overactive bladder (OAB) who suffered from nocturia.
Methods: A total of 60 OAB patients with a mean age of 74 years (45 men and 15 women) who mainly complained of nocturia were enrolled. Imidafenacin (0.1 mg) was administered once daily before sleeping for four weeks. Then the patients were divided into two groups, “a stable-dose group” with sufficient efficacy who remained on 0.1 mg of imidafenacin daily, and “a dose-escalation group” with insufficient efficacy in whom the daily dose of imidafenacin was increased to 0.2 mg before sleeping. Lower urinary tract symptoms and postvoid residual volume (PVR) were examined before treatment and after 4 and 8 weeks of imidafenacin therapy.
Results: In the stable-dose group, nighttime frequency decreased significantly from 3.4 ± 1.1 to 2.3 ± 1.1 and 2.6 ± 2.0 times after four and eight weeks, respectively. In the dose-escalation group, nighttime frequency did not change significantly (from 3.8 ± 1.5 to 3.6 ± 1.8 times) at four weeks, but decreased significantly to 2.8 ± 1.4 times at eight weeks. Daytime frequency, OAB symptom score, and IPSS-QOL index score were significantly improved in both groups at four and/or eight weeks. There was no increase of PVR and no serious adverse events.
Conclusion: Administration of imidafenacin at 0.1–0.2 mg once daily before sleeping was safe and effective for the treatment of OAB with the main symptom of nocturia.