worldwide , the human life span and the proportion of elderly people in the population have both increased . various changes occur in the human body with age . in elderly men , lower urinary tract symptoms ( luts ) and sexual dysfunction several community - based studies have shown strong correlations between the prevalence of sexual dysfunction , especially erectile dysfunction ( ed ) , and the severity of luts with increasing age . this coexistence of sexual problems with luts negatively affects the quality of life ( qol ) . the prevalence of luts and sexual dysfunction increases with age in korea , and both present synchronously in many cases . consequently , effort has been directed at determining the pathophysiology common to these conditions , including hyperactive adrenergic signaling , increased rho - kinase and endothelium activity , and decreased nitric oxide ( no ) levels in genital tissue . premature ejaculation ( pe ) is also seen in the elderly as a primary or secondary condition . in many countries , by contrast , in korea , the prevalence of pe in the sixth decade is 36.8% vs. 24.6% in the third decade . the reason for the increased prevalence of pe with age has not been determined , but it could be related to conditions such as luts and ed . if the increased prevalence of pe during old age in korea is the result of increasing secondary pe compared to primary pe , then a correlation may exist between ed or luts in middle - aged to elderly men with pe . therefore , this study examined the correlations among luts , ed , and pe in korean men older than 40 years . this study enrolled 258 men older than 40 years presenting between june 2010 and march 2011 in busan , korea . all subjects were from the general population and had participated in a health care lecture in busan . men between 40 and 79 years old who were willing and able to participate in the study were included . subjects who were younger than 40 years old or older than 79 years old were excluded . all subjects were assessed by using the international prostate symptom score ( ipss ) , a 5-item version of the international index of erectile function ( iief-5 ) from the ed domain of the iief , and a validated korean version of the premature ejaculation diagnostic tool ( pedt ) . the ipss was categorized into the total score , storage symptoms ( st ) , and voiding symptoms ( vd ) . the relationships among the storage symptoms , voiding symptoms , iief-5 scores , and pedt scores were analyzed . the statistical analyses were performed by using spss ver . 17.0 ( spss inc . , student 's t - test was used to examine the differences in the ipss - st , ipss - vd , ipss - total , iief-5 , and pedt between the age groups . spearman 's rank correlation analysis was used to examine the correlations of the ipss and iief-5 with the pedt and each other . the study enrolled 258 men : 55 ( 21.32% ) were 40 to 59 years old and 203 ( 78.68% ) were 60 to 79 years old . the mean ipss , iief , and pedt were 12.67 , 14.14 , and 8.05 , respectively . using the pedt , the prevalence of pe was 29.1% versus a self - reported incidence of 49.5% . comparing the age groups ( 40 to 59 vs. 60 to 79 years old ) , no significant correlations were observed in the total and subscale scores of the ipss and pedt ( ipss - st , p=0.081 ; ipss - vd , p=0.413 ; ipss - total , p=0.204 ; pedt , p=0.309 ) . however , a significant negative correlation was detected between the iief score and age ( p=0.002 ) . the meansd iief-5 score was 15.835.427 in those aged 40 to 59 years old and 13.695.833 in those aged 60 to 79 years old ( table 1 ) . comparing the assessment scales in the 40 to 59 year - old age group , the pedt score was significantly correlated with iief ( r=-0.323 , p=0.018 ) , but was not correlated with ipss - st ( r=0.327 , p=0.077 ) , ipss - vd ( r=0.223 , p=0.235 ) , or ipss - total ( r=0.284 , p=0.128 ) . the iief-5 score was not correlated with ipss - st ( r=-0.222 , p=0.255 ) , ipss - vd ( r=-0.096 , p=0.628 ) , or ipss - total ( r=-0.192 , p=0.327 ) ( table 2 ) . comparing the assessment scales in the 60 to 79 year - old age group , the pedt score was significantly correlated with the ipss - st ( r=0.318 , p=0.003 ) , ipss - total ( r=0.292 , p=0.007 ) , and iief-5 ( r=-0.250 , p<0.001 ) , but was not correlated with the ipss - vd ( r=0.196 , p=0.075 ) . the iief-5 score was significantly negatively correlated with the pedt ( r=-0.250 , p<0.001 ) , but was not correlated with the ipss - st ( r=-0.158 , p=0.162 ) , ipss - vd ( r=-0.174 , p=0.122 ) , or ipss - total ( r=-0.197 , p=0.079 ) ( table 3 ) . comparing the domains of the iief-5 with each domain of the pedt , questions 1 , 4 , and 5 of the pedt were significantly negatively correlated with all domains of the iief-5 . the frequencies of the pe and ejaculation with minimal sexual stimulation domains were significantly correlated with the intercourse satisfaction domain of the iief-5 . ejaculation is triggered by efferent dopamine acting on the d2 receptors of central and spinal efferent fibers , which relay information down to the sympathetic ganglia at t10-l2 and the sacral fibers . this stimulates pudendal nerve fibers from the s2-s4 region of the spinal cord , resulting in smooth muscle contractions of the prostate , seminal vesicles , vas deferens , and epididymis . this increases the volume and fluid content of semen , which is forced into the posterior urethra under the control of the sympathetic nervous system , producing emission . the diagnostic and statistical manual of mental disorders , 4 edition , test revision ( dsm - iv - tr ) defines pe as " the persistence of recurrent ejaculation with minimal sexual stimulation before , on , or shortly after penetration and before the person wishes it and it causes marked distress or interpersonal difficulty and is not due to the direct effects of a substance " . primary pe ( lifelong ) occurs and persists from the first sexual encounter , whereas secondary pe ( acquired ) transpires after a period of normal control of ejaculatory function . one study reported that 91% of men with primary pe had a first - degree relative with pe . secondary pe is due to psychological or relationship problems , ed , prostatitis , or thyroid dysfunction . the most common cause of secondary pe is declining erectile function , whereby rapid ejaculation becomes a compensatory mechanism , either consciously or unconsciously , for the inability to maintain the erection . an alternative explanation is that lower levels of no and increased sympathetic tone , associated with aging , both predispose men to erectile failure and hasten ejaculation [ 11 - 13 ] . the pedt has been found to have a high level of agreement with clinical diagnosis , and its test - retest reliability has been shown to be good , with an intra - class correlation coefficient of 0.88 . the pedt consists of five questions that address the following five domains : ejaculation control , frequency of pe , ejaculation with minimal sexual stimulation , distress , and interpersonal difficulty . each question has five responses , and the scores of each question range from 0 to 4 with a minimum total score of 0 and a maximum score of 20 . a low score suggests a low probability of having pe . in the premature ejaculation perceptions and attitudes study however , according to the data of the korean society for sexual medicine and andrology , koreans demonstrate an increased pe prevalence with increasing age ; these data support the above hypothesis and concur with our data . furthermore , ejaculation with very little stimulation and the frequency of pe were not correlated with ed . erection firmness and erection maintenance ability were correlated with the control of ejaculation , as seen in secondary pe . the proposal has been made that the use of a pde-5 inhibitor ( e.g. , sildenafil ) may increase the level of no centrally ( reducing sympathetic drive ) and peripherally ( leading to smooth muscle dilatation of the vas deferens and seminal vesicles , opposing sympathetic vasoconstriction ) , probably prolonging the intravaginal ejaculation latency time ( ielt ) in men with pe . nitric oxide synthase isoenzymes are present in human seminal vesicle smooth muscle , and the no - cgmp and no - camp signaling pathways are not only involved in the relaxation of human penile smooth muscles but also affect smooth muscle relaxation in the vas deferens , seminal vesicle , prostate , urethra , and skeletal muscles . in a randomized placebo - controlled study of men with primary pe without ed , sildenafil did not significantly prolong the ielt , but it was associated with a perception of greater control over ejaculation in men receiving active therapy . our cross - sectional study showed that an improvement in ed was correlated with an improvement in pe . however , we did not examine the correlation between the use of pde-5 inhibitors and pe . several community - based studies have shown strong correlations between the prevalence of sexual dysfunction , especially ed , and the severity of luts with increasing age . in our study , the ipss - st , ipss - vd , ipss - total , and pedt scores were not significantly correlated with age . only the iief-5 score had a significant correlation with age . the pathophysiological mechanism of the correlations among luts , ed , and pe remains unclear , although several hypotheses have been proposed [ 18 - 21 ] . one possible cause is overactivation of the autonomic nervous system and increased sympathetic nervous system activity . according to this hypothesis , luts could result from sympathetic nervous system tone , which induces the occurrence of urinary storage symptoms owing to the contraction of smooth muscles in the prostate gland and urinary bladder . pe occurs as a result of smooth muscle contraction in the prostate , seminal vesicle , vas deferens , and epididymis [ 18 - 21 ] . however , this hypothesis has not been confirmed in experimental studies . in our study , the pedt score was significantly correlated with the ipss - st , ipss - total , and iief-5 scores in the 60 to 79 year - old age group . the pedt score was significantly correlated with ipss - st ; however , it was not correlated with ipss - vd . pe seems to correlate with luts and erectile dysfunction , and storage symptoms seemed to be correlated with pe more than voiding symptoms in the 60 to 79 year - old men in our study . some luts result from increased sympathetic tone and storage symptoms , which were related more to the pedt score , and are associated with increased sympathetic tone rather than voiding symptoms . irwin et al .   reported that an overactive bladder was significantly associated with an increased prevalence of ed and that sexual activity , sexual enjoyment , and sexual satisfaction were reduced as the result of urinary symptoms . in our study , however , the iief-5 score had the only significant correlation with the pedt score . the iief-5 score was not significantly correlated with the ipss - st , ipss - vd , or ipss - total . in fact , our previous study revealed that the iief-5 score was significantly negatively correlated with the ipss - total , especially ipss - st . the reason for this difference can be explained by the fact that the population of the previous study consisted of patients with luts , whereas the population in the current study was a general population who did not visit the hospital at the time the questionnaire was administered . therefore , a smaller proportion of the population of this study complained of luts . in recent years , many studies have reported that the administration of alpha - blockers improves luts and sexual dysfunction . other studies have reported that not only the bladder neck , urethra , and prostate , but also the seminal vesicle and vas deferens show a typical distribution for alpha - adrenoceptors , which accounts for their capacity to affect ejaculation , as reported in clinical studies in men with prostatic hyperplasia ( up to 7% of cases reported with tamsulosin ) . almost no reports have addressed the effects of antimuscarinic agents on sexual function in luts . our study showed that pe was significantly correlated with luts , particularly storage symptoms , in the 60 to 79 year - old age group rather than the 50 to 69 year - old age group . in our study , no information on the patients ' medical history was collected . to address this limitation , a well - designed , larger - scale assessment of the relationship and treatment of luts , ed , and pe korean middle - aged to elderly men frequently experience pe , which is significantly correlated with ed . in addition , luts , particularly storage symptoms , have a negative effect on pe . an improvement in storage symptoms could positively affect men with pe and ed , and the storage symptoms of luts may play an important role in the treatment of pe in middle - aged to elderly korean men .
purposeto evaluate the correlation between lower urinary tract symptoms ( luts ) and premature ejaculation ( pe ) in korean men older than 40 years.materials and methodsin total , 258 men older than 40 years completed the international prostate symptom score ( ipss ; total score , storage symptoms [ st ] , and voiding symptoms [ vd ] ) , a 5-item version of the international index of erectile function ( iief-5 ) , and the premature ejaculation diagnostic tool ( pedt ) . 
 the study examined the relationship between luts and pe . in the pedt 
 , pe is defined as a score 11.resultsthe prevalence of pe was 29.1% with the pedt versus a self - reported value of 49.5% . 
 the prevalence of pe was 30.9% in 40 to 59-year - old men ( 21.3% ) and 28.1% in 60 to 79 year - old men ( 78.7% ) . 
 in men 40 to 59 and 60 to 79 years old , the mean pedt , ipss , and iief-5 scores were 8.65 and 7.88 , 13.5 and 12.38 , and 15.83 and 13.69 , respectively . 
 no significant correlations were observed between the total and subscale scores of the ipss ( p=0.204 ) and the pedt ( p=0.309 ) with increasing age , whereas a significant negative correlation was detected between the iief-5 and age ( p=0.002 ) . 
 the pedt score was significantly correlated with the ipss - st ( r=0.326 , p<0.001 ) , ipss - vd ( r=0.183 , p=0.005 ) , ipss - total ( r=0.310 , p<0.001 ) , and iief-5 total ( r=-0.248 , p<0.001).conclusionsluts , especially storage symptoms , were related to pe . in elderly men , control of both erectile 
 dysfunction and luts may play an important role in managing pe .