.Chiung-Kun Huang^1,2, Chih-Chieh Lin^1,2, Alex T.L. Lin^1,2

Department of Urology, Taipei Veterans General Hospital¹

Department of Urology, School of Medicine and Shu-Tien Urological Institute, National Yang-Ming University, Taipei, Taiwan²

黃烱焜^1,2、林志杰^1,2、林登龍^1,2

台北榮民總醫院 泌尿部¹

國立陽明大學醫學院 泌尿學科 書田泌尿科學研究中心²

Both antimuscarinics and beta-3-adrenoceptor agonist are generally accepted first line pharmacotherapy for overactive bladder (OAB). From the published articles and guideline, there is no consensus in which kind of medication was better choice for patients with OAB. The objective of this research is to assess the clinical characteristic and manifestation between different medication subgroups from real-world data. 

 

In this retrospective, single center study, we recruited all patients aged more than 18 years old, who meet the criteria and definition of overactive bladder (OAB) proposed by international continence society in 2002. From January 2010 to December 2017, patients were prescribed more than 4-week medication with antimuscarinics or beta-3-adrenoceptor agonist (Mirabegron) at our institute. Patients were divided to three subgroups according to antimuscarinics (group A), beta-3 adrenoceptor agonist group (group B), and discontinued group (group C). All patients received questionnaires including OABSS and quality of life (QoL) before and after medication. Global improvement scale of Clinical Global Impression (CGI) was recorded for treatment outcome evaluation (Defining good response as CGI=1,2,3; poor response as CGI=4,5,6). Some patients received urodynamic evaluation before medication. In the statistical analysis, Pearson's chi-squared test was used to evaluate the incidence of underlying diseases among the three subgroups. All urodynamic parameters and questionnaires among three subgroups were statistically analyzed with the Mann-Whitney U test.

 

Of overall 215 patients including in this study, there were 43 patients (20%) allocated in subgroup A, 35 patients (16.2%) in subgroup B, and 137 patients (63.8%) in subgroup C. The patient’s gender and underlying disease among three subgroups revealed no significant difference. However, the mean age of subgroup B (77.4 yrs, range from 49 to 95) is statistically older than subgroup A (69.2 yrs, 31-91, p = 0.012) and subgroup C (68.6 yrs, 20-90, p = 0.001). In urodynamic study, all urodynamic parameters showed no statistically significant difference among three subgroups, except the cystometric (CMG) capacity. Patients in subgroup A have significantly larger CMG capacity (Mean ± SD,  257.3±135.1 cc) than subgroup B (125.8±46.0 cc, p = 0.002) and subgroup C (170.5±99.2 cc, p = 0.001). Except the drop-out subgroup C, the mean medication duration of antimuscarinics (group A, 527.0 days, 28~1980) showed no significant difference to that of beta-3 adrenoceptor agonist (group B, 516.4 days, 112~1925) (p = 0.9). Among these three subgroups before medication, there is no significant difference in questionnaires, such as OABSS score, QoL. Nevertheless, difference in questionnaire before and after medication was significantly noted in OABSS total score of subgroup A(4.81±2.81 ) and subgroup B (4.17±2.85). As compared to drop-out subgroup, OABSS total score of both antimuscarinics and beta-3 adrenoceptor agonist showed statistically significant improvement ( p = 0.001, and p = 0.028, respectively). The QoL after medication and CGI showed better response in both treatment subgroups. However, better CGI (1, 2, 3) of group A (97.7%) revealed no significant difference to that of group B (94.3%). We further analyzed the difference in subscore of every OABSS scale before and after treatment. It also showed no difference between group A and group B in each four questions (day time frequency score, night time frequency score, urgency score, urge incontinence score).

 

Patients of medication with antimuscarinics is significant younger in age and have larger CMG capacity. Both antimuscarinics and beta 3 adrenoceptor agonist are effective medication. However, there is no significant difference in effectiveness between these two pharmacotherapy subgroups.