Hypothesis / aims of study
Post micturition dribble is one of the bothersome lower urinary symptoms (LUTS) because of incontinence-like symptom. However, urinary questionnaires have rarely addressed this symptom, and post micturition dribble is difficult to assess because patients have difficulties to tell the difference of post micturition dribble and terminal dribble. Therefore, limited data is available on the prevalence of post micturition dribble.
Tadalafil is a relatively novel drug to treat lower urinary tract symptoms with benign prostatic hyperplasia. Tadalafil has multi-mechanisms for improvement of LUTS including smooth muscle relaxation. increased blood perfusion, decreased afferent nerve activity, and decreased smooth muscle cell proliferation. In this background, Tadalafil may have a potential to improve post micturition dribble. However, no previous data on the efficacy of Tadalafil on post micturition dribble was found. The aim of this study is to assess the prevalence of post micturition dribble in clinical setting and evaluate the effect of Tadalafil on this symptom.
Study design, materials and methods
This study included 101 urological male outpatients to assess the prevalence of post micturition dribble, and 18 patients with post micturition dribble to evaluate the effect of Tadalafil on the symptom. Post micturition dribble was evaluated simultaneously with terminal dribble and residual urine feeling using a new questionnaire we developed with four grading scale of frequency (none, rarely, sometimes and frequently) and bother of these symptoms (none, mild, moderate and severe). Treatment efficacy of Tadalafil on post micturition dribble was evaluated with Patient Global Impression of Improvement after four weeks treatment with 5mg of Tadalafil. Patients with LUTS was defined as ≥7 point in I-PSS score and ≥3 in QOL score.
Survey was conducted for 101 urological male outpatients: 51 patients had LUTS and 50 patients did not have LUTS according to IPSS and QOL score. Mean age of the subjects was 69 years. The prevalence of PMD was 23% in all patients and 39% in LUTS patients. Patients who bothered worse than moderately with PMD was 16% in all patients and 29% in LUTS patients. Frequency and bother of PMD, terminal dribble and residual urine feeling were significantly higher in patients with LUTS than in patients without LUTS (p<0.05, Fig. 1). The prevalence of terminal dribble was the most frequent among three symptoms, but the most bothersome symptoms was post micturition dribble. After four weeks of Tadalafil treatment, 33% of patients improved very much better and 50% improved better. In total, 83% improved more than better category.
Interpretation of results
This study revealed that patients with LUTS was likely to have post micturition dribble. Moreover, the most bothersome symptom was post micturition dribble, while the prevalence of terminal dribble was the most frequent among three symptoms. This result indicated that post micturition dribbles was bothersome and should be a target of treatment. In this context, post micturition dribble should be included in LUTS questionnaire. Our questionnaire would help clinician to know the frequency and bother of post micturition dribble as well as terminal dribble and residual urine feeling.
Tadalafil was associated with significant improvement in post micturition dribble. The cause of post micturition dribble was not well understood. It is hypothesized that residual urine in the bulbous urethra is leaking after lifting up their underwear. Tadalafil has multi-mechanisms for improvement of LUTS including smooth muscle relaxation. increased blood perfusion, decreased afferent nerve activity, and decreased smooth muscle cell proliferation. This study suggested that Tadalafil might support the function of bulbous urethra by improved function of microvessels or muscles directly or indirectly.