document: from a worldwide perspective , the life span of humans has been prolonged , and the proportion of elderly people in the total population has increased . 
   various changes occur in the human body with age . in elderly men , lower urinary tract symptoms ( luts ) , erectile dysfunction ( ed ) , and decreased libido often appear concurrently . 
   several community - based studies have shown a strong correlation among sexual dysfunction , increasing age , and the severity of luts . 
   this coexistence of sexual problems with luts and benign prostatic hyperplasia ( bph ) further affects quality of life ( qol ) . 
   luts and ed share increased prevalence as age increases , and in many cases , the two are synchronously present . 
   thus , continuous efforts have been made to disclose the common pathophysiology between these two conditions . 
   no definite explanations have been given to clarify the pathophysiological mechanism of the correlation between luts and ed , but several hypotheses have been proposed [ 2 - 5 ] . 
   one possible cause is overactivation of the autonomic nervous system and increased tension of the sympathetic nervous system . 
   according to this hypothesis , luts increases sympathetic nervous system activity , which induces the occurrence of urinary storage symptoms due to the contraction of smooth muscles in the prostate gland and urinary bladder . 
   ed occurs as the result of smooth muscle contractions in the corpus spongiosum , and the myosin light chain is phosphorylated because of increased rho - kinase activity , which can cause smooth muscle layer contraction . 
   it has been proposed that endothelial dysfunction in the prostate gland and corpus spongiosum and hormonal imbalance are physiological causes for the correlation between luts and erectile dysfunction . 
   changes in lifestyle due to nocturia and rapid eye movement sleep disorder may affect the occurrence of erectile dysfunction . 
   also , the result of our preliminary study showed that age , international prostate symptom score ( ipss ) , nocturia , and the uroflow rate correlated significantly with the 5-item version of the international index of erectile function ( iief-5 ) . even in cases in 
   which age was controlled for , qol was found to have a significant correlation with sexual function . 
   prostate gland volume was not significantly correlated with sexual function , implying that erectile function is not affected by subjective luts even with a relatively greater prostate size . 
   irwin et al reported that overactive bladder ( oab ) was significantly associated with increased prevalence of ed and that sexual activity , sexual enjoyment , and sexual satisfaction were reduced as the result of urinary symptoms . in recent years , many studies have reported that administration of alpha - blockers improves luts due to bph and sexual dysfunction . 
   these findings suggest that rudimentary treatments of luts , a risk factor for erectile dysfunction , would be mandatory to effectively improve sexual function in patients with bph who concurrently have luts and ed . 
   the primary treatment regimen for bph is to administer alpha - blockers , for which the main mode of action is based on smooth muscle relaxation in the prostate and the resulting improvement in the urinary flow rate and voiding symptoms . 
   however , a synchronous improvement of irritative and voiding symptoms may be the most effective treatment regimen for luts / bph . 
   it is expected that the concomitant administration of alpha - blockers and anticholinergics would improve luts more effectively in patients with luts / bph . 
   these effects are also expected to have a positive effect in secondarily improving sexual function . 
   thus , the aim of this study was to examine the effects on erectile function of a combination of the alpha - blocker tamsulosin to improve luts and the antimuscarinic agent solifenacin to improve irritative symptoms of the bladder . 
   male patients aged 40 years or older who had concurrent luts / bph and ed were enrolled in this study . 
   inclusion criteria were an ipss total score > 12 , an ipss - qol score > 3 , and an iief-5 score < 20 . 
   exclusion criteria were as follows : 1 ) antiandrogens administered in the 4 weeks previously for the management of bph or luts ; 2 ) sex hormone agents or pde-5 inhibitors administered in the 4 weeks previously for the management of male sexual dysfunction ; 3 ) surgical treatment of the prostate gland or urethra ; 4 ) diagnosis of urethral stricture , urinary tract infection , prostatitis , prostate cancer , or bladder cancer ; 5 ) psa > 4 mg / dl ; 6 ) severe renal dysfunction or hepatic dysfunction ; 7 ) residual urine > 100 ml ; and 8) ineligibility for the current study as judged by the investigators . 
   sixty male patients between the ages of 41 and 76 years with luts / bph and ed were divided into two groups by using a table of random sampling numbers : group 1 ( the alpha - blocker treatment group ; n=30 ) and group 2 ( the alpha - blocker+solifenacin treatment group ; n=30 ) . in group 1 , an alpha - blocker ( tamsulosin 0.2 mg q.d . ) 
   was solely administered for 3 months . in group 2 , an alpha - blocker and an antimuscarinic drug ( tamsulosin 0.2 mg and 
   solifenacin 5 mg q.d ) were concomitantly administered during the same period . in patients who were suspected of having a significant bladder outlet obstruction ( postvoiding residual urine > 100 ml or maximum flow rate < 5 ml / s ) , solifenacin was not administered . to examine the correlation between luts and the degree of erectile function , ipss and iief-5 
   then , prostate - specific antigen ( psa ) , transrectal ultrasonography ( trus ) , urine flowmetry ( ufm ) , and residual urine ( ru ) were measured . 
   ipss was categorized into total scores , storage symptoms ( st ) , voiding symptoms ( vd ) , and quality of life ( qol ) . in group 1 , in which tamsulosin was solely administered ( n=30 ) for 3 months , and group 2 , in which tamsulosin and solifenacin were concomitantly administered ( n=30 ) for 3 months , 
   comparative analyses were also done to examine the linear relationship between ipss scores and iief-5 scores before and after treatment in the two groups . the t - test ( t ) and mann - whitney u - test were used to compare parameters indicating the degree of luts and sexual function between the two groups , such as trus , psa , ipss ( total , vd , and st ) , ipss - qol , iief-5 total , amount of urination , amount of ru , maximal urinary flow rate ( qmax ) , and mean urinary flow rate ( qave ) . by use of the paired t - test ( t ) and wilcoxon signed rank test ( z ) 
   , a comparative analysis was performed on each group for ipss ( vd , st , total ) , ipss - qol , iief-5 total , the amount of urination , the amount of ru , qmax , and qave before and after treatment . 
   regression analysis was used to inspect the linear relationship between ipss scores and iief-5 scores before and after treatment in the two groups . 
   the t - test ( t ) and mann - whitney u - test were used to compare parameters indicating the degree of luts and sexual function between the two groups , such as trus , psa , ipss ( total , vd , and st ) , ipss - qol , iief-5 total , amount of urination , amount of ru , maximal urinary flow rate ( qmax ) , and mean urinary flow rate ( qave ) . by use of the paired t - test ( t ) and 
   wilcoxon signed rank test ( z ) , a comparative analysis was performed on each group for ipss ( vd , st , total ) , ipss - qol , iief-5 total , the amount of urination , the amount of ru , qmax , and qave before and after treatment . 
   regression analysis was used to inspect the linear relationship between ipss scores and iief-5 scores before and after treatment in the two groups . 
   of a total of 60 study patients , 1 patient in group 1 and 3 patients in group 2 dropped out of the 3-month follow - up study . 
   therefore , analyses were performed on 29 patients in group 1 and 27 patients in group 2 . 
   the incidences of hypertension and diabetes were 11 and 3 in group 1 and 9 and 5 in group 2 , respectively . before treatment , no significant differences ( p<0.05 ) were found between groups 1 and 2 , respectively , in age ( 59.176.73 yr vs. 56.410.80 yr ) , prostate gland size ( 27.18.0 g vs. 28.438.18 g ) , psa levels ( 1.090.97 mg / dl vs. 1.180.80 mg / dl ) , amount of urination ( 245.86160.97 ml vs. 223.36125.76 ml ) , amount of ru ( 2434.50 ml vs. 32.239.79 ml ) , qmax ( 14.417.16 ml / s vs. 14.806.1 ml / s ) , or qave ( 7.333.62 ml / s vs. 8.063.53 ml / s ) . 
   no significant differences were found in iief-5 ( 12.456.85 vs. 12.047.65 ) or ipss - qol ( 4.280.88 vs. 3.820.88 ) scores . 
   however , the ipss total score was significantly higher ( p<0.05 ) in group 1 than in group 2 ( 20.287.39 vs. 15.225.55 ) . 
   this was due to the exclusion of patients in group 2 who were suspected of having significant bladder outlet obstruction ( postvoiding residual urine > 100 ml or maximum flow rate < 5 ml / s ) . in both groups 1 and 2 , the ipss total , 
   ipss - vd , ipss - st , and ipss - qol scores were significantly improved after the 3-month treatment ( p<0.05 ) . however , no significant differences in the iief-5 total score , amount of urination , amount of ru , qmax , or qave were found before or after treatment ( table 1 ) . a comparison of the change (  ) in luts and sexual function after treatment between group 1 and group 2 revealed no significant differences in ipss total ( 5.726.90 vs. 4.155.72 ) , ipss - vd ( 3.694.77 vs. 2.044.71 ) , ipss - st ( 2.243.50 vs. 2.112.33 ) , ipss - qol ( 0.831.47 vs. 0.821.04 ) , or iief-5 
   a comparison of the degree of improved sexual function ( iief-5 ) associated with improved luts in each patient ( ipss total , ipss - vd , ipss - st , and ipss - qol ) showed significant improvement in the iief-5 score associated with the degree of improvement in the ipss - st domain ( ipss - st ) in group 1 , but no significant associations were found in group 2 ( table 3 , fig . 
   1 ) . in cases in which tamsulosin was administered , the iief-5 score significantly improved as the ipss - st domain score improved . in the group in which tamsulosin and solifenacin were concomitantly administered , 
   improvement of the ipss - st domain score had no significant effect on the iief-5 score . 
   luts / bph is the most common disease of lower urinary tract obstruction that occurs in men aged 60 years or older . in most cases , it develops slowly , but in some patients , it progresses rapidly . 
   the incidence of both bph and ed is increased in elderly people , and the synchronous occurrence of luts and ed is considered to happen as the result of aging . even in cases 
   in which age and underlying disease such as cardiovascular disease , diabetes mellitus , and hypertension were statistically controlled , epidemiologic studies have shown a definite correlation between bph and ed . 
   these two disease entities are not due to aging , but they share a common pathophysiology . 
   thus , a synergistic effect whereby the treatment of one disease would lead to improvement in the other disease is expected . 
   conversely , khler and mcvary reported that the improved sexual function resulting from treatment with pde-5 inhibitors led to improved luts . 
   a questionnaire study of 12,815 men aged 50 years or older found a significant correlation between bph and ed . 
   furthermore , age and luts were found to be greater risk factors for ed than were organic factors such as diabetes mellitus , hypertension , and hyperlipidemia . in our series , age had the highest degree of correlation with sexual function . voiding symptoms of the ipss , storage symptoms , qol , 
   nocturia symptoms , residual urine , maximal urinary flow rate , and mean urinary flow rate were significantly correlated with the degree of sexual satisfaction as well as with erectile function . 
   luts accompanied by bph can be divided mainly into voiding ( obstructive ) symptoms and storage ( irritative ) symptoms . 
   however , little is known about which of the various symptoms are more closely associated with ed . it remains unclear which luts might effectively improve the concurrent presence of ed , and a substantial number of studies in recent years have aimed to resolve this issue . 
   this study was also performed to investigate which symptoms of bph , obstructive or irritative symptoms , are closely related to erectile function . 
   morant et al reported that both irritative and voiding symptoms are significantly correlated with sexual function . 
   tsai et al reported that irritative symptoms are more highly correlated with ed than are obstructive symptoms . 
   a preliminary study that we conducted in patients with bph found a significant correlation between sexual function and various irritative and voiding symptoms , qol , nocturia , residual urine , and urine flow rates . 
   following a 3-month treatment of luts with alpha - blockers , the improvement in voiding symptoms , qol , and average flow rate was significantly correlated with improved sexual function . to date , however , few studies have reported similar results , and controversy remains . 
   storage symptoms due to oab may cause a higher degree of pain than do voiding symptoms . in cases of bph accompanied by oab , 
   for this reason , the use of anticholinergic agents ( or antimuscarinic agents ) has been attempted in patients with oab accompanied by bph . 
   several previous studies have confirmed the efficacy and safety of concomitant administration of alpha - blockers and anticholinergic agents . 
   even so , in some cases , residual urine is increased or voiding symptoms are aggravated following the use of anticholinergic agents , and in patients with luts / bph , anticholinergic agents are used selectively . in our series , we excluded patients who likely had a significant bladder outlet obstruction ( pvr > 100 ml or qmax < 5 ml / s ) and who had luts / bph ; we therefore found significantly improved luts with no complications such as acute urinary retention . 
   common side effects following the use of anticholinergic ( or antimuscarinic ) agents are dry mouth , constipation , blurred vision , headache , and dry eye , but almost no reports have described the effects on sexual function . 
   some concern exists that the use of anticholinergic ( or antimuscarinic ) agents in patients with bph may lead to aggravation of voiding difficulty or the development of urinary retention . to date , urologists have not actively used anticholinergic ( or antimuscarinic ) agents , but many types of antimuscarinic agents have been used in recent years to treat oab in a clinical setting . 
   as related experiences have accumulated , these drugs have been selectively used for patients with luts / bph . 
   almost no reports have addressed the effects of antimuscarinic agents on sexual function in luts / bph patients . in a study of 39 men with bph and luts 
   in whom previous alpha - blocker therapy had failed , kaplan et al found normal sexual function in 27 ( 63% ) and 29 ( 67% ) patients before and after administration , respectively . 
   no reports have indicated that the administration of anticholinergic ( or antimuscarinic ) agents significantly impairs sexual function . in our series , a comparison of iief-5 scores before and after concomitant drug treatment with solifenacin and tamsulosin revealed no statistically significant changes . 
   thus , it can be inferred that administration of anticholinergic ( or antimuscarinic ) agents had no significant effect on sexual function . in patients with luts 
   / bph , concomitant treatment with alpha - blockers and antimuscarinics may lead to improvement in luts , but this treatment can not be expected to improve sexual function . 
   in patients with luts / bph and ed , concomitant use of tamsulosin and solifenacin was effective for improving luts . 
   however , sexual function was not significantly improved by the concomitant administration of alpha - blockers and antimuscarinics .
summary: purposeto examine the effects on erectile function of concomitant treatment with an alpha - blocker ( tamsulosin ) and an antimuscarinic agent ( solifenacin ) in patients with lower urinary tract symptoms ( luts)/benign prostatic hyperplasia ( bph).materials and methodsfifty - seven male patients with luts / bph were assessed for the degree of luts and erectile function . in group 1 ( tamsulosin ) and group 2 ( tamsulosin and solifenacin ) , changes in the international prostate symptom score [ ipss : total scores , storage symptoms ( st ) , voiding symptoms ( vd ) , and quality of life ( qol ) ] , prostate - specific antigen , trans - rectal ultrasonography , urine flowmetry , residual urine , and a 5-item version of the international index of erectile function ( iief-5 ) were assessed after a 3-month treatment period . in both groups , it was determined whether treatment was associated with changes in luts and erectile function and whether improvement in the ipss was correlated with the iief-5 . 
   comparative analysis was also done to examine the linear relationship between improved ipss scores and iief-5 scores.resultsa comparison of the degree of improvement in all the parameters indicated that both groups showed significant improvement in total ipss , ipss - st , ipss - vd , and ipss - qol ( p<0.05 ) . 
   a comparison of the degree of improved sexual function associated with improved luts in each patient showed significant improvement in the iief-5 score associated with the degree of improvement in the ipss - st domain in group 1 , but no significant associations were found in group 2 . in cases 
   in which tamsulosin was administered , the iief-5 score significantly improved as the ipss - st domain score improved . in the group in which tamsulosin and solifenacin were concomitantly administered , 
   improvement of the ipss - st domain score had no significant effect on the iief-5 
   score.conclusionsin patients with luts / bph , tamsulosin and solifenacin combination therapy was effective for luts , but erectile function was not significantly improved . 
   therefore , although effective for improving luts , combination therapy with an alpha - blocker and an antimuscarinic agent was not effective for improving erectile function .