4. Discussion
According to International Continence Society, PMD is defined as “involuntary loss of urine immediately after he or she has finished passing urine, usually leaving after the toilet for men or after rising from the toilet for women” 15. It is a symptom of LUTS, but cannot be assessed with in the widely used symptom questionnaires such as IPSS, DAN-PSS-1 16. These questionnaires have been validated to evaluate BPH or obstructive pathologies affecting the lower urinary system; nevertheless, they do not contain a query for PMD 13,17. Therefore, current literature is insufficient to evaluate PMD and lacking detailed reports of PMD compared with other urinary symptoms. Recently, Jeong et al.12 have developed a multidimensional tool (HPMDQ) to evaluate PMD; however, further studies are required to prove its clinical utility.
In this study, the validity and reliability of the Turkish version of HPMDQ were evaluated using the data collected from PMD patients residing in Turkey. For assessing the reliability, the test-retest reliability and inter-item correlation of HPMDQ were evaluated. The IIC for this study was 0.727, which provided a sufficient condition for clinical trials. For each item in HPMDQ, weighted kappa coefficients ranging from 0.628 to 0.838 were found. The highest weighted kappa coefficient was for the fourth question (quality of life), while the lowest weight was for the amount of PMD. For internal consistency, a Cronbach α value of 0.903 was calculated, and it was determined that the survey was valid.
Most of the previous published reports on PMD have focused on the prevalence of PMD rather than its clinical significance. The prevalence of PMD in the male population varied in a wide range in the literature. This could be caused by the various tools that were used to evaluate the PMD. Besides, some studies categorised patients symptomatic if they had symptoms at least “sometimes” , but some other studies defined the symptomatic patients as they had symptoms at least “fairly often”5,10. Nevertheless, more recent studies have shown that the prevalence rates of PMD are around 30-60%4,10,11,18. In the HPMDQ development study, the prevalence rate of PMD in 2134 patients was found 51%, which is consistent with our findings as the 52.3% of the participants were symptomatic.
Previous studies have also shown that PMD is positively associated with aging men and BPH, but this symptom can also occur in young adults and impair quality of life 18,19. While enlargement of the prostate in aging men explains the pathophysiological mechanism of PMD, its occurrence in young and middle ages indicates that other factors are interwoven in its pathophysiology. In a urodynamic study, it has been shown that the bulbocavernosus contraction insufficiency at the end of micturition causes PMD with pooling of urine in the bulbar urethra20. In several different studies, it was thought that the weakening of the urethra-corpora cavernosal reflex with a similar mechanism could cause both erectile dysfunction and PMD and that these two diseases were found related to each other 21,22.
Regarding the clinical significance of PMD, the data on literature is scarce. In the BACH study, post micturition symptoms were more closely associated with voiding symptoms than the storage symptoms5. Similarly, Jeong et al. found that the HPMDQ total score was significantly correlated with the voiding symptoms of LUTS, PVR and prostate size but not with the irritative (storage) symptoms of LUTS 12. In a Japanese-men based study, PMD did not show significant association with prostate volume and peak flow rate18. In our study, PMD showed a significant correlation with total IPSS score, voiding symptoms of LUTS and PVR, indicating that Turkish version of HPMDQ can reflect PMD well, as in the original development study.
Considering the treatment options for PMD, bulbar urethral massage and pelvic floor exercise (PFE) are the recommended treatment strategies. The rationale behind these treatments is based on the hypothesis that weakened pelvic floor muscle might induce PMD. It was shown that while bulbar urethral massage may show immediate treatment effect, PFE may need longer times to take effect (3 to 6 months)23,24. In this study, we recommended bulbar urethral massage method to patients and found that it is an effective and safe method for relieving PMD. Currently, no pharmacological treatment has been established to relieve PMD, but recently a 75 mg of udenafil has been introduced as an effective treatment for PMD 25.
Several factors may limit the extrapolation and transferability of findings from this study. First, we did not include female patients as PMD is seen in males more common and the original symptom assessment tool (HPMDQ) was developed on male patients with LUTS12. Second, we did not use paper test to measure the amount of PMD, instead we relied on the self-assessments of the patients with PMD. Third, to evaluate the fifth question only bulbar urethral massage was suggested as a treatment method. Although PFE was shown to be more effective than bulbar urethral massage in relieving PMD, bulbar urethral massage has also proven itself as a simple and effective self-help technique in the literature 26,27.
In conclusion, The Turkish version of HPMDQ, which assesses the different aspects of PMD including frequency, severity, amount and discomfort has been developed and determined as a reliable tool for evaluating patients with PMD. PMD was also significantly correlated with IPSS scores, which generally assess the severity of LUTS. This study also showed that bulbar urethra massage is an effective method to relieve PMD. This simple questionnaire would aid researchers in clinical studies and facilitate the understanding of medical applications’ responses among Turkish speaking patients with PMD.
Funding:
None