Irritable Bowel Syndrome Is Associated Not Only With Organic but Also Psychogenic Erectile Dysfunction

C-Y Hsu; C-L Lin; C-H Kao


Int J Impot Res. 2015;27(6):233-238. 

In This Article


The correlation between IBS and PED has not yet been identified. To our knowledge, this is the first population-based study to identify IBS as a contributing factor for both PED and OED. We found that patients with IBS were more likely to develop erectile dysfunction (ED) than were those without IBS. After adjusting for age, year of index date and medical comorbidities (CAD, COPD, CKD, hypertension, diabetes, hyperlipidemia, depression and anxiety), patients with IBS were 2.12 times more likely to develop OED and 2.38 times more likely to develop PED than were the controls.

IBS is a common clinical gastrointestinal disorder. However, the pathogenesis of IBS is unclear. Several theories have been proposed. Serotonin imbalance caused visceral sensitivity or gastrointestinal motility leading to IBS.[8,9] Stasi et al.[10] found that plasma cortisol was linearly related to plasma serotonin in patients with IBS. Because cortisol was an inhibitor in penile erection,[11] it had a significant inverse correlation with penile rigidity.[12] Therefore, serotonin regulation might play a leading role in IBS and ED.

A recent meta-analysis study showed that IBS was caused by cytokines imbalance.[13] In 2004, Giugliano et al.[14] described that ED could by caused by endothelial dysfunction through impaired nitric oxide availability from inflammatory cytokines. Bouloukaki et al.[15] confirmed that inflammatory cytokines were involved in endothelial dysfunction as the pathogenesis of ED. They found that ED was associated with increasing levels of inflammatory cytokines. Cytokines were strongly related to the pathophysiologic mechanism of IBS and ED. SK-3, one of the small-conductance Ca2+-activated K+ (SK) channels members, was highly expressed in smooth-muscle-rich tissues such as the gastrointestinal tract and the corpus cavernosum. Chen et al.[16] considered that a high presentation of SK-3 involved in the smooth muscle of the gastrointestinal tract and the corpus cavernosum led to IBS and ED. The association between IBS and ED were existed.

Psychological disorders such as depression and anxiety are risk factors of IBS.[1] An Indian study showed that the prevalence of depression and anxiety was 37.1 and 31.4% in patients with IBS, and the odd ratios were 6.3 and 7.6 for depression and anxiety. The prevalence of depression and anxiety in IBS is relatively high. The authors suggested that screening for anxiety and depression might be necessary in patients with IBS.[17] Zhang et al.[18] reported that crucial psychogenic factors related to ED are anxiety and depression. Sugimori et al.[19] found that patients with a combination of depression and anxiety had a significantly higher prevalence of ED than did the control. Depression and anxiety were associated with IBS and ED. We considered that anxiety and depression are risk factors for developing ED, because our population-based results show that patients with comorbidities of depression and anxiety had a higher risk of developing OED and PED compared to the control.

Stress exposure could increase the gastrin-releasing peptide level, which might stimulate the release of the adrenocorticotropic hormone and cortisol.[20] Cortisol has an inhibitory role in penile erection,[11] and a had significant inverse correlation with penile rigidity.[12] Sakamoto et al.[21] demonstrated that PED could be triggered by stress, which can involve the gastrin-releasing peptide system that is the primary mediator for male reproductive function. IBS as stress for affected people could induce ED.

Regarding comorbidities, the risk of developing OED was greater for patients with comorbidities of CKD, diabetes and hyperlipidemia; the risk of developing PED was greater for patients with the comorbidity of anxiety. The associations between ED and comorbidities are well defined. Several studies demonstrated that high prevalence of hyperlipidemia or diabetes was found in patients with ED.[22,23] We confirmed the results, atherosclerosis of blood vessels caused by hyperlipidemia or diabetes was strongly associated with OED in our study. Our finding also supported the correlation between anxiety and PED. However, regarding the powerful influence for PED, the IBS was stronger than the other comorbidities.

The strength of this study is identifying the correlation between IBS and OED and PED using a nationwide population-based data set, which can avoid the selection bias. However, this study has several limitations. First, because IBS diagnosis was made by individual physicians, we could not determine whether the diagnosis was confirmed by Manning, Rome II or Rome III criteria, or colonscopy. Second, disease severity was not included in the NHIRD; diarrhea-predominant, constipation-predominant or mixed-type of IBS could not be measured. Third, patient's characteristics such as diet, lifestyle, marital status or smoking were unavailable from the NHIRD, which could involve gastrointestinal and sexual function. Fourth, because the confidential law in Taiwan to prevent us to check the personal chart for individual patient, we could not do manual chart extraction or informatics approaches to confirm the absence of codes (for example, diabetes mellitus, hypertension, prostate cancer and so on) that would suggest misclassification of an organic ED as psychogenic. Finally, because medication for ED is not covered by the NHI program, numerous ED patients seek alternative treatment. Self-payment for ED treatment might not be recorded in the NHIRD. However, our nationwide population-based data that avoids selection bias provides the sufficient statistical power for analysis.