Efficacy of cinnamon patch treatment for alleviating symptoms of overactive bladder: A double-blind, randomized, placebo-controlled trial

Background: Current treatments for overactive bladder (OAB) have limited efficacy, low persistence and a high rate of adverse events commonly leading to treatment cessation in clinical practice. Clinicians in Asia commonly use traditional Chinese medicine as an alternative for OAB treatment despite it having uncertain efficacy and safety. To evaluate the efficacy and safety of cinnamon patch (CP) treatment for alleviating symptoms of OAB, a double-blind randomized, placebo-controlled trial was conducted in the present study. Materials and Methods: In this 6-week randomized clinical trial conducted in an outpatient setting, 66 subjects diagnosed as having OAB were enrolled and treated with a placebo (n=33) or CP (n=33). The OAB symptom score (OABSS) was selected as the primary end point, and a patient perception of bladder condition (PPBC), an urgency severity scale (USS), and post-voiding residual urine (PVR) volume were selected as secondary end points. Statistical analyses were performed with IBM SPSS Statistics 20. Groups were compared using an independent sample t-test, Fisher exact test, and Chi-squared test. Results: In total, 66 participants (40 women and 26 men), 60.35 ± 12.77 years of age, were included in the intention-to-treat analyses. Baseline characteristics were comparable between the CP (n ==33) and placebo (n ==33) groups. Treatment with a CP showed statistically significant differences in reductions in OABSS scores (9.70 ± 2.20 to 6.33 ± 2.42), PPBC scores (3.36 ± 0.60 to 2.15 ± 0.83), and USS scores (2.67 ± 0.54 to 1.64 ± 0.60). Conclusions: Compared to a placebo, treatment with CP might be considered an effective and safe complementary therapy for OAB. Further studies employing a positive control, different dosage forms, larger sample sizes, and longer treatment periods are warranted.