Vardenafil is effective and well-tolerated for treating erectile dysfunction in a broad population of men, irrespective of age

A web-based survey of erection hardness score and its relationship to aging, sexual behavior, confidence, and risk factors in Japan

Introduction

Erection hardness is an elemental component of men's sexual quality of life that can be easily measured by the Erection Hardness Score (EHS). However, there are few published data regarding EHS, and there is little understanding of its relationships to aging, men's sexual behavior, sexual confidence, and risk factors in Japan.

Aim

To assess EHS and how it correlates to aging, sexual behaviors, sexual self-confidence, and risk factors in a Japanese population database.

Methods

A web-based cross-sectional nationwide survey conducted between March and May 2009 in Japan.

Main Outcome Measures

EHS, lifestyle factors, comorbidities, general health, sexual confidence, frequency of sexual behaviors, and attitudes toward treatment of erectile dysfunction (ED).

Results

A total of 7,710 men with a mean age of 39.3 ± 13.0 years participated in this survey. In 6,528 participants who were not using phosphodiesterase type 5 inhibitors, 3,540 (54.2%) had EHS ≤ 3 and 1,196 (18.3%) had EHS ≤ 2. We found a significant age-dependent decrease in EHS, sexual confidence, and frequency of sexual activities. Sexual confidence was strongly associated with higher EHS but was also associated with older age groups, presence of offspring, awareness of better general health, and greater frequency of sexual activity. In age-adjusted multivariate logistic regression, risk factors for a lower EHS (defined as EHS ≤ 2) were heavy smoking, which was defined as more than two packs per day (odds ratio [OR], 1.7) or a history of metabolic syndrome (OR, 1.4), hypertension (OR, 1.2), and diabetes mellitus (OR, 1.4).

Conclusions

EHS correlates to various elements, such as aging, sexual behaviors, sexual confidence, and ED-related risk factors, and can be a valuable tool in clinical practice for monitoring and treating ED and thereby improving the quality of life for men and their sexual partners. Kimura M, Shimura S, Tai T, Kobayashi H, Baba S, Kano M, and Nagao K. A web-based survey of Erection Hardness Score and its relationship to aging, sexual behavior, confidence, and risk factors in Japan. Sex Med 2013;1:76–86.

Medical management of erectile dysfunction in aging males: is it too late to treat?

Erectile dysfunction (ED) is a common disorder among aging males. However, most aging males refuse to seek medical help and believe that ED is an irreversible event in the aging process. The purpose of this study was to describe the current medical management of ED in aging males and to examine whether it is too late to treat this disorder in these elderly men. From 2007 to 2008, 4507 patients diagnosed with ED were gathered from 46 centers in China; 4241 completed the study, 3837 of whom were treated with sildenafil. The 3837 patients were divided into five groups based on age (group A: 20–30 years; group B: 31–40 years; group C: 41–50 years; group D: 51–60 years; and group E: >60 years). After comparing pre- and posttreatment International Index of Erectile Function-Erectile Function domain (IIEF-EF) questionnaires, Erection Hardness Scale (EHS), and IIEF Q13 (“How satisfied have you been with your overall sex life?”), we discovered that the aging males had worse erectile function, erection hardness, and sexual satisfaction than the younger males (P < 0.001). After treatment, the improvement rates in the IIEF-EF, EHS, and IIEF Q13 scores were 107.0%, 83.1%, and 116.5%, respectively. The magnitude of these changes demonstrated significant differences among groups (P < 0.001). Accordingly, aging males are likely to benefit more from medical treatment. We propose that aging males should be informed that age is not a limiting factor for medical ED management, and it is never too late to treat.

Erectile dysfunction in the elderly: an old widespread issue with novel treatment perspectives

Erectile dysfunction (ED) is one of the most common chronic diseases affecting men and its prevalence increases with aging. It is also the most frequently diagnosed sexual dysfunction in the older male population. A number of different diseases potentially worsening sexual function may occur in elderly people, together with polypharmacy. Related causes of ED are variable and can include arterial, neurogenic, hormonal, cavernosal, iatrogenic, and psychogenic causes. The aim of the present review was to examine the main aspects of erectile dysfunction going through epidemiology and pathophysiology and revise most of ED in elderly disabled men and in those affected with psychiatric disorders. Lastly we tried to focus on the main aspects of nonpharmacological and pharmacological treatments of ED and the recreational use in the elderly. Phosphodiesterase-5 inhibitors (PDE5-I) are commonly used for on-demand or chronic treatment of ED. It is widely known that PDE5-I have lower response rates in older men than in younger patients, but they have the advantages of ease of use and excellent safety profile, also in the elderly. The old and new PDE5-I as well as the alternative treatments for ED are extensively discussed.

Evaluation and treatment of erectile dysfunction in the aging male: a mini-review

Before the 20th century, individuals often did not live beyond the reproductive years, and sexuality of the elderly was not an issue. However, in the current era it is known that as life expectancy improves, both men and women are seeking to preserve their sexuality into old age. While the appreciation of sexuality persists with aging, a decline in sexual activity is typically seen with, and can be attributed to both general health problems as well as specific sexual dysfunctions. Erectile dysfunction is the most frequently diagnosed sexual dysfunction in the older male population. This mini-review provides an overview of contemporary literature concerning epidemiology, pathophysiology, assessment and treatment of erectile dysfunction in the aging male.

Effect of the phosphodiesterase 5 inhibitors sildenafil, tadalafil and vardenafil on rat anococcygeus muscle: functional and biochemical aspects

1. The anococcygeus muscle is part of the erectile machinery in male rodents. Phosphodiesterase (PDE) 5 inhibitors enhance and prolong the effects of cGMP, which has a key role in penile erection. The aim of the present study was to provide a functional and biochemical comparison of the three PDE5 inhibitors, namely sildenafil, tadalafil and vardenafil, in the rat anococcygeus muscle. 2. Muscle strips were mounted in 4 mL organ baths and isometric force recorded. Levels of cGMP were measured using an enzyme immunoassay kit. Western blots were used to determine PDE5 protein expression. 3. The PDE5 inhibitors concentration-dependently relaxed carbachol-precontracted anococcygeus muscle; however, vardenafil was more potent (pEC(50) = 8.11 +/- 0.05) than sildenafil (7.72 +/- 0.06) or tadalafil (7.69 +/- 0.05). Addition of N(G)-nitro-l-arginine methyl ester (100 micromol/L) or 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (10 micromol/L) to the organ baths caused significant rightward shifts in concentration-response curves for all PDE5 inhibitors. 4. Sildenafil, tadalafil and vardenafil (all at 0.1 micromol/L) caused leftward shifts in the glyceryl trinitrate (GTN) concentration-response curves (by 4.0-, 3.7- and 5.5-fold, respectively). In addition, all three PDE5 inhibitors significantly potentiated relaxation responses to both GTN (0.01-10 micromol/L) and electrical field stimulation (EFS; 1-32 Hz), with vardenafil having more pronounced effects. 5. All three PDE5 inhibitors reduced EFS-evoked contractions in a concentration-dependent manner over the concentration range 0.001-1 micromol/L. There were no significant differences between the effects of the three PDE5 inhibitors. 6. Vardenafil (0.01-0.1 micromol/L) was more potent in preventing cGMP degradation in vitro than sildenafil (0.01-0.1 micromol/L) and tadalafil (0.01-0.1 micromol/L). 7. Under control conditions, the expression of PDE5 was higher in the anococcygeus muscle than in the corpus cavernosum. 8. In conclusion, PDE5 inhibitors enhance exogenous and endogenous nitric oxide-mediated relaxation in the rat anococcygeus muscle. The potency of vardenafil was greater than that of either sildenafil or tadalafil.

Tadalafil is efficacious and well tolerated in the treatment of erectile dysfunction (ED) in men over 65 years of age: results from Multiple Observations in Men with ED in National Tadalafil Study in the United States

INTRODUCTION

Erectile dysfunction is increasingly common with advancing age, yet sexual activity and intimacy are important to elderly men.

AIM

To assess the efficacy and tolerability of tadalafil in men over the age of 65 years.

METHOD

In this multicenter open-label study, 188 men (mean age = 71.6 years) who were over age 65 and did not have diabetes mellitus or clinical depression received tadalafil 20 mg, taken on demand, for up to 12 weeks.

MAIN OUTCOME MEASURES

Efficacy was assessed using the International Index of Erectile Function (IIEF) and Sexual Encounter Profile (SEP). Psychosocial outcomes were evaluated using the Psychological and Interpersonal Relationship Scale (PAIRS).

RESULTS

Tadalafil treatment significantly improved all domains of the IIEF from baseline, including the erectile function (EF) domain (change = 8.8, end point = 21.6; P < 0.001). Mean per-patient percentage of "yes" responses to SEP questions concerning successful penetration (SEP2; change = 33.5%, end point = 73.5%; P < 0.001) and successful intercourse (SEP3; change = 39.6%, end point = 59.6%; P < 0.001) also improved significantly from baseline. Forty percent of the patients with baseline EF scores < 26 had normal EF (IIEF-EF domain scores > or = 26) at end point, and 81% reported improved erections in the Global Assessment Questionnaire. At least 56% of attempts at sexual intercourse were successfully completed (SEP3) at all time intervals up to 36 hours after tadalafil administration. The patients also experienced significant improvement in both the sexual self-confidence and spontaneity domains of the PAIRS. Tadalafil was well tolerated, with < 5% of the patients discontinuing because of adverse events.

CONCLUSION

Tadalafil 20 mg was effective and well tolerated in elderly men with ED.

Efficacy of tadalafil once daily in men with diabetes mellitus and erectile dysfunction

AIMS

Erectile dysfunction (ED) is a common comorbidity in men with diabetes mellitus. Tadalafil 10 or 20 mg taken on demand is efficacious and safe for men with diabetes and ED. Recently, continuous treatment with tadalafil has been proposed, addressing ED management as any other chronic condition. This study examined whether once-daily tadalafil 2.5 and 5 mg is efficacious for men with diabetes and ED.

METHODS

This randomized, double-blind, placebo-controlled, multicentre, 12-week study enrolled 298 men with diabetes and ED to once-daily treatment with placebo, tadalafil 2.5 mg or tadalafil 5 mg. Primary efficacy measures were International Index of Erectile Function Erectile Function (IIEF EF) Domain score, and patient success rates for vaginal penetration and completion of intercourse. Patient satisfaction, endothelial function biomarkers, and safety were also assessed.

RESULTS

Patients receiving either dose of tadalafil had clinically and statistically significant improvements in IIEF EF and statistically significant improvements in mean success rates for vaginal penetration, completion of intercourse, and overall treatment satisfaction (P < or = 0.005 tadalafil vs. placebo, all measures). Endothelial dysfunction biomarkers were unchanged. The most common adverse events were headache, back pain and dyspepsia.

CONCLUSIONS

In this first study of men with diabetes and ED, once-daily tadalafil 2.5 and 5 mg was efficacious and well tolerated, suggesting this may be an alternative to on-demand treatment for some men, eliminating the need to plan sex within a limited timeframe.

Vardenafil: a selective inhibitor of phosphodiesterase-5 for the treatment of erectile dysfunction

Vardenafil is a selective phosphodiesterase-5 inhibitor approved for the treatment of erectile dysfunction. It was found to be effective in a high percentage of patients and a broad spectrum of underlying conditions. It potentiates the increase in intracellular cGMP in the corpora cavernosa in response to sexual stimuli, resulting in enhanced and prolonged erections. The overall tolerability and safety profile is acceptable, with headache, flushing, rhinitis and dyspepsia being the major reported side effects. Importantly, tolerability and safety in cardiovascular patients seems to be good with no significant increase in cardiovascular events that could be directly attributed to the pharmacologic agent. Only mild blood-pressure lowering effects were observed in healthy individuals, as well as hypertensive patients on multiple antihypertensive agents. However, special caution is mandatory if vardenafil is administered in combination with alpha-blockers, as significant hypotension might occur. Importantly, any drug serving as a nitric oxide donor is contraindicated in combination with vardenafil.

Does the clinical efficacy of vardenafil correlate with its effect on the endothelial function of cavernosal arteries? A pilot study

OBJECTIVE

To investigate whether the results of the ultrasonographic (US) measurement of post-occlusive changes in the diameters of cavernosal arteries after administering phosphodiesterase type 5 (PDE-5) inhibitor vardenafil could be associated with the response to vardenafil in patients with erectile dysfunction (ED), as currently there are no reliable methods for predicting the success rate of oral PDE-5 inhibitors.

PATIENTS AND METHODS

The study included 122 men with ED; after a complex evaluation, the endothelial function of the cavernosal arteries was assessed in all patients before and 1 h after oral ingestion of vardenafil (20 mg), using our modification of the US assessment of post-occlusive changes in the diameter of cavernosal arteries. After the evaluation, all patients received vardenafil 20 mg on demand for 4 weeks. A successful response was defined using two endpoints, i.e. the normalization of the International Index of Erectile Function Erectile Function domain score (> or = 26) and positive answers to both Sexual Encounter Profile questions 2 and 3 on > or = 75% of occasions, based on the diary data collected.

RESULTS

In all patients the mean (sd) initial percentage increase in the cavernosal artery diameter (PICAD) in responders and nonresponders was not statistically different, at 49 (24) and 43 (26), respectively (P = 0.168), but PICAD values after vardenafil were significantly greater in responders, at 73 (16) vs 55 (23) (P < 0.001). Analysis of data from patients with different causes of ED showed statistically significant differences in PICAD between responders and nonresponders only in those with arteriogenic ED. The sensitivity and specificity of a PICAD of > or = 50% after taking vardenafil 20 mg for predicting a positive response to the same dose of the drug in patients with arteriogenic ED were 94.9% and 91.3%, respectively.

CONCLUSION

The results of the US assessment of post-occlusive changes in the diameter of cavernosal arteries after vardenafil administration are significantly associated with the clinical efficacy of the drug in patients with arteriogenic ED.

Vardenafil rescue rates of sildenafil nonresponders: Objective assessment of 327 patients with erectile dysfunction

OBJECTIVES

To prospectively investigate whether vardenafil can effectively treat patients for whom sildenafil (100 mg) has failed. The introduction of two new oral phosphodiesterase type 5 inhibitors (tadalafil and vardenafil) raises the question of whether the new agents will permit us to treat sildenafil nonresponders with another oral agent.

METHODS

Patients were seen at one institution during a 5-year period. A total of 327 patients complaining of sildenafil-refractory erectile dysfunction underwent intracavernous pharmacologic injection and color duplex Doppler ultrasonography. Subsequently 59 of these men tried vardenafil home dosing.

RESULTS

Of the 327 men in whom sildenafil failed, 16% were younger than 50, 21% were 51 to 60, 34% were 61 to 70, and 28% were older than 70 years. The Doppler diagnoses were arterial insufficiency in 154 (47%), mixed vascular insufficiency in 73 (22%), and cavernous venous occlusive disease in 57 (17%). Forty-three men (13%) had normal erectile responses to prostaglandin E1 (10 to 20 microg). Of the 59 men who tried vardenafil, 19% were younger than 50, 17% were 51 to 60, 40% were 61 to 70, and 23% were older than 70 years. The Doppler diagnoses were arterial insufficiency in 28 (42%), mixed vascular insufficiency in 10 (19%), and cavernous venous occlusive disease in 15 (29%). Six men (8%) had normal erectile responses to prostaglandin E1. Only 7 (12%) of the 59 men reported that home vardenafil dosing resulted in successful intercourse.

CONCLUSIONS

An appropriate diagnostic evaluation and subsequent treatment algorithm have yet to be established for those for whom phosphodiesterase type 5 inhibitors fail. We found that most sildenafil nonresponders had severe arterial insufficiency and were older, with 62% older than 60 years. Our preliminary experience suggests that only a small percentage (12%) of sildenafil nonresponders can be salvaged with vardenafil.

Mechanisms of direct relaxant effect of sildenafil, tadalafil and vardenafil on corpus cavernosum

Sildenafil, tadalafil, vardenafil and verapamil induced concentration-dependent relaxation of the rabbit corpus cavernosum muscle precontracted with noradrenaline. The maximal relaxation (%) at 20 microM was 61.4 +/- 6.9, 32.4 +/- 5.4, 100.0 +/- 5.5 and 86.6 +/- 5.1 (n = 5 each) respectively. Pre-incubation of cavernosal muscle strips with N(omega)-nitro-L-arginine or guanylate cyclase inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) but not adenylate cyclase inhibitor, cis-N-[2-phenylcyclopentyl]-azacyclotridec-1-en-2-amine] (MDL12330A) culminated in only a 20-30% reduction in muscle relaxant action of the 3 phosphodiesterase inhibitors. This suggests that another mechanism of relaxation independent of nitric oxide-cGMP or cAMP pathway was involved. Higher concentrations of sildenafil (100 microM) and vardenafil (10 and 100 microM) produced non-competitive antagonism of noradrenaline-induced contraction characterized by reduced maximal effect. In contrast, tadalafil was devoid of significant effect on noradrenaline. On K(+)-depolarized tissues, sildenafil was as potent as vardenafil whereas tadalafil was the least effective in relaxing K(+)-induced tone. The maximal relaxation (% of K(+)-induced tone) at 20 microM sildenafil, tadalafil and vardenafil was respectively 84.1 +/- 6.5, 9.0 +/- 19.9, and 88.9 +/- 6.2 (n = 5 each). In addition, verapamil, sildenafil and vardenafil were more efficacious than tadalafil in reversing tonic contractions by Ca(2+) channel activator, 1,4,dihydro-2,6-dimethyl-5-nitro-4-[2(triflouromethyl)phenyl]pyridine-3-carboxylic acid methyl ester (BAY K-8644). These results indicate that vardenafil and sildenafil possess direct muscle relaxant potential possibly via inhibiting Ca(2+) influx through both receptor-operated and voltage-dependent Ca(2+) channels whereas tadalafil appears capable of inhibiting receptor-operated transmembrane Ca(2+) entry only.

Clinical update on phosphodiesterase type-5 inhibitors for erectile dysfunction

Erectile dysfunction (ED) affects the sexual lives of millions of men. The first-line oral pharmacotherapy for most ED patients is phosphodiesterase type-5 (PDE-5) inhibitors, of which three are available. Sildenafil is the most widely prescribed oral agent for ED and has a very satisfactory efficacy-safety profile in all patient categories. Tadalafil and vardenafil were introduced in the European Union and in the United States in 2003 and 2004, respectively. The three PDE-5 inhibitors share many pharmacological and clinical characteristics, and each has unique features. This review, which is based on the contemporary literature on PDE-5 inhibitors, describes the chemical, pharmacological, and clinical features of sildenafil, vardenafil, and tadalafil. The first section reviews the pathophysiology of penile erection and PDE-5 inhibitor pharmacology. The second section summarizes data regarding efficacy and safety of the three drugs in treating ED in the general population as well as in selected patient categories.