Efficacy of sildenafil citrate (Viagra) for the treatment of erectile dysfunction in men in remission from depression

Pharmaceutical management of sexual dysfunction in men on antidepressant therapy

INTRODUCTION

Sexual dysfunction (SD) and depression have a bidirectional relationship. The rising prescription of antidepressants, especially those with a serotonergic effect, is associated with increased SD. Sexual dysfunction reduces compliance and increases risk of recurrence of depressive episodes. Various strategies have been studied to manage antidepressant-induced SD.

AREAS COVERED

This review covers the identification of symptoms of antidepressant-induced SD, prevalence of symptoms in association with commonly used antidepressants, and the main lines of management, with a focus on pharmacological strategies.

EXPERT OPINION

The management of antidepressant-induced SD aims to reduce the unwanted sexual adverse effects while maintaining an acceptable control of depressive symptoms. It should implicate a multidisciplinary approach and determination of baseline sexual function and SD risk factors. In spite of several methodological issues, antidepressants can be divided into low- and high-risk categories with regard to the possibility of developing SD. In patients interested in sexual activity, it is recommended to start with low-risk antidepressants. Otherwise, encourage the patient to wait for tolerance and then switch to low-risk. In selected cases, dose reduction or a drug holiday may be applied. The adjunctive use of a PDE5i can help in a significant number of patients. Randomized controlled trials are needed to set high-level evidence-based recommendations.

Sildenafil citrate in the treatment of pain in primary dysmenorrhea: a randomized controlled trial

STUDY QUESTION

Is a vaginal preparation of sildenafil citrate capable of alleviating acute menstrual pain in patients with primary dysmenorrhea (PD)?

SUMMARY ANSWER

A vaginal preparation of sildenafil citrate is capable of alleviating acute menstrual pain in patients with PD with no observed adverse effects.

WHAT IS KNOWN ALREADY

Oral preparations of nitric oxide (NO) donor drugs augment relaxant effects of NO on myometrial cells, reverse the vasoconstriction caused by prostaglandins and successfully alleviate pain, but the incidence of side effects is too high for routine clinical use. Sildenafil citrate inhibits type 5-specific phosphodiesterase (PDE5), thus preventing the degradation of cyclic guanosine monophosphate (cGMP) in the muscle and augmenting the vasodilatory effects of NO. Therefore, by inhibiting PDE5, the tissue remains relaxed and more blood can circulate through. It has been used previously in a vaginal form with no observed side effects, and it enhances endometrial blood flow.

STUDY DESIGN, SIZE, DURATION

A double-blind, randomized, controlled trial comparing vaginal preparation of sildenafil citrate (100 mg single dose) to a placebo in 62 PD patients at the time of painful menstruation was conducted. The primary outcome was total pain relief over 4 consecutive hours (TOPAR4) comparing sildenafil citrate to placebo, where higher TOPAR4 scores represent better pain relief. Secondary outcomes were pain relief as measured by the visual analog scale (VAS) and uterine artery pulsatility index (PI). Subjects were recruited from December 2007 to January 2011. The trial was stopped due to closeout of the funding for the study.

PARTICIPANTS, SETTINGS, METHODS

Participants were women in good health, were aged 18-35 years and suffered from moderate to severe PD. They were randomized to either vaginal placebo or 100 mg vaginal sildenafil citrate in a 1:1 ratio using random permuted blocks having a block size of 4. At baseline and 1, 2, 3, and 4 h post-treatment, patients were asked to provide assessment of their degree of pain using two scales: (i) pain on the 5-level ordinal scale used for TOPAR4 calculation and (ii) pain level on the VAS. The study ended 4 h after treatment initiation.

MAIN RESULTS AND THE ROLE OF CHANCE

Twenty-five subjects completed the study. Using the TOPAR4 score, the sildenafil citrate group had significantly better pain relief compared with the placebo group [mean (SD): 11.9 (3.2) versus 6.4 (2.1), respectively; difference in means = 5.3; 95% CI: (2.9,7.6); P < 0.001)]. On the VAS, sildenafil citrate provided better pain relief than placebo at each time point. At the 2-h time point, the PI was significantly lower in the sildenafil citrate group compared with the placebo group [mean (SD): 1.6 (0.6) versus 2.3 (0.5), respectively; difference in means = -0.7; 95% CI: (-1.2, -0.1); P = 0.01)].

LIMITATIONS, REASONS FOR CAUTION

Since we did not meet our sample size due to the loss of funding and could not confirm our primary hypothesis, larger studies of longer duration, likely multi-center, are needed to confirm the findings from this study.

WIDER IMPLICATIONS OF THE FINDINGS

A number of medications have been investigated to improve the treatment options for PD, but most have proven unsuccessful or to have an unfavorable risk/benefit ratio. Since PD is a condition that most women suffer from and seek treatment for at some point in their lives, our study offers hope that vaginal sildenafil citrate is a safe and effective option for patients who do not desire or are unresponsive to treatments now available on the market.

STUDY FUNDING/COMPETING INTERESTS

Funding for this study was provided by National Institutes of Health (NIH) grants RO3 TW007438 and K24 HD01476. The authors report no relevant conflicts of interest.

TRIAL REGISTRATION NUMBER

NCT00123162 (Clinical trials.gov).

Strategies for managing sexual dysfunction induced by antidepressant medication

BACKGROUND

Sexual dysfunction (including altered sexual desire, orgasmic and ejaculatory dysfunction, erectile and other problems) is a relatively common side effect of antidepressant medication. These sexual side effects may compromise a person's lifestyle and result in a lack of compliance with the prescribed antidepressant to the detriment of the person's mental health. A wide range of management strategies are possible to address this problem, including behavioural, psychological and pharmacological approaches.

OBJECTIVES

1. To determine the effectiveness of management strategies for sexual dysfunction caused by antidepressants.2. To determine the adverse effects and acceptability of the different management strategies.

SEARCH METHODS

We searched the Cochrane Depression, Anxiety and Neurosis Group's Specialized Register (CCDANCTR, to 1 January 2013), which includes relevant randomised controlled trials from the following bibliographic databases: The Cochrane Library (all years), EMBASE (1974 to date), MEDLINE (1950 to date) and PsycINFO (1967 to date). Additional searches were carried out by the author team on the same biomedical databases (using terms for 'sexual dysfunction' only) together with CINAHL (1982 to Jan 2012). The reference lists of reports of all included studies were screened.

SELECTION CRITERIA

We included randomised controlled trials that compared management strategies for antidepressant-induced sexual dysfunction versus placebo or any alternative strategy.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and assessed trial quality. Study authors were contacted for additional information.

MAIN RESULTS

We included 23 trials involving 1886 people in this updated review. Twenty-two of these trials investigated the addition of medication to treat the identified dysfunction, with most agents studied in only single studies. One study investigated switching to an alternative antidepressant.In men, data for the phosphodiesterase inhibitors sildenafil (three studies, 255 participants) and tadalafil (one study, 54 participants) indicated they led to a greater improvement in erectile function than placebo. Combined data from three sildenafil studies found benefit over placebo on International Index of Erectile Function ratings of ability to achieve (MD 1.04, 95% CI 0.65 to 1.44), and maintain erections (MD 1.18, 95% CI 0.78 to 1.59). A single point improvement on these ratings is equivalent to an improvement in frequency from 'sometimes' to 'most times'. Men receiving tadalafil were more likely to report improved erectile function (RR 11.50, 95% CI 3.03 to 43.67). For women it remains uncertain whether sildenafil is more effective than placebo. Unpublished data could reduce this uncertainty.Data from three studies in men and women of bupropion 150 mg twice daily indicate a benefit over placebo on rating scale scores (SMD 1.60, 95% CI 1.40 to 1.81), but response rates in two studies of bupropion 150 mg once daily demonstrated no statistically significant difference in effect (RR 0.62, 95% CI 0.09 to 4.41).Other augmentation strategies failed to demonstrate significant improvements in sexual dysfunction compared with placebo.One trial involving 75 people with sexual dysfunction due to sertraline assessed the effect of changing antidepressant. Switching to nefazodone was significantly less likely to result in the re-emergence of sexual dysfunction than restarting sertraline (RR 0.34, 95% CI 0.19 to 0.60), however, nefazodone is no longer available for clinical use.There is an absence of randomised trials assessing the effects of switching to currently-available antidepressant agents with lower rates of adverse sexual effects, the role of psychological or mechanical interventions, or of techniques such as drug holidays.We identified no data for any of the strategies included in the trials assessed that indicated that they led to a worsening of psychiatric symptoms. However, the relatively small numbers assessed for many of the interventions studied means that the possibility of such an effect cannot confidently be excluded in all cases.Given the small numbers of studies assessing most of the strategies assessed, the presence of any unpublished trials could have substantial effects on estimates of effect. In some cases, only results from particular items or subscales within ratings scales are available. It is likely that this could act to bias estimates of effect obtained, increasing apparent effectiveness.

AUTHORS' CONCLUSIONS

The evidence currently available is rather limited. For men with antidepressant-induced erectile dysfunction, the addition of sildenafil or tadalafil appears to be an effective strategy. For women with antidepressant-induced sexual dysfunction the addition of bupropion at higher doses appears to be the most promising approach studied so far.

An update on pharmacological treatment of erectile dysfunction with phosphodiesterase type 5 inhibitors

INTRODUCTION

Phosphodiesterase type 5 inhibitors (PDE5-i) are used for the oral treatment of erectile dysfunction (ED). Since the launch of sildenafil more than 15 years ago, new molecules have become available. At present, in addition to tadalafil and vardenafil, there are three other drugs, udenafil, avanafil and mirodenafil, marketed in some countries which appear to be promising.

AREAS COVERED

The clinical pharmacological differences in dosage and side effects of all PDE5-i are evaluated.

EXPERT OPINION

All PDE5-i are equally effective and safe for the treatment of ED. On-demand use of any PDE5-i is also safe for patients with comorbid conditions. Tadalafil seems to be the preferred drug by patients and physicians, probably due to its peculiar pharmacological profile that makes sexual intercourse more spontaneous for the patients. Preliminary data suggest that the use of vardenafil may also be beneficial in cases of ED associated with premature ejaculation. Daily treatment is another option in men with ED and documented vascular or prostate disease. In geriatric or in difficult-to-treat populations, the evaluation of testosterone plasma levels will help to predict the efficacy of any PDE5-i. Remarkably, when such drugs are withdrawn for any reason, ED most often continues to occur because of the presence of an underlying disease.

Influence of sildenafil on the antidepressant activity of bupropion and venlafaxine in the forced swim test in mice

Recent studies highlight the involvement of the nitrergic system in the mechanism of action of antidepressant drugs. Sildenafil, a selective PDE5 inhibitor, was shown to abolish the anti-immobility effects of bupropion, venlafaxine and s-citalopram in mice. In this study we assessed the effects of sildenafil on the activity of bupropion and venlafaxine in the forced swim test in mice. Swim trials were conducted by placing mice in glass cylinders filled with water for 6min and the duration of the behavioral immobility during the last 4min of the test was evaluated. Locomotor activity was evaluated with photoresistor actimeters. Brain and serum concentrations of the studied antidepressants were determined by HPLC method. Sildenafil at a dose of 20mg/kg, but not 5 and 10mg/kg, significantly increased the anti-immobility action of bupropion (20mg/kg). The antidepressant activity of venlafaxine (2mg/kg) was potentiated by joint administration with sildenafil at doses of 10 and 20mg/kg. Since the combined treatments did not increase the locomotor activity, the antidepressant-like effects were not related to non-specific behavioral activation. Data from pharmacokinetic studies revealed that sildenafil increased bupropion and venlafaxine levels in serum without affecting their concentrations in the brain. The present study demonstrates the enhancement of anti-immobility action of bupropion and venlafaxine by sildenafil co-administration. The observed changes might have been partly due to pharmacokinetic interactions. However, mechanisms underlying the effects of sildenafil on the antidepressant activity of bupropion and venlafaxine should be carefully evaluated in further studies.

Sildenafil, a phosphodiesterase type 5 inhibitor, enhances the antidepressant activity of amitriptyline but not desipramine, in the forced swim test in mice

The cholinergic theory of depression highlights the involvement of muscarinic acetylcholine receptors in the neurobiology of mood disorders. The present study was designed to investigate the effect of sildenafil, a phosphodiesterase type 5 inhibitor which exhibits cholinomimetic properties, alone and in combination with scopolamine in the forced swim test in mice. Moreover, we assessed the ability of sildenafil to modify the antidepressant activity of two tricyclic antidepressants with distinct cholinolytic activity, amitriptyline and desipramine. Swim sessions were conducted by placing mice in glass cylinders filled with water for 6 min and the duration of behavioral immobility during the last 4 min of the test was evaluated. Locomotor activity was measured with photoresistor actimeters. To evaluate the potential pharmacokinetic interaction between amitriptyline and sildenafil, brain and serum concentrations of amitriptyline were determined by HPLC. Sildenafil (1.25-20 mg/kg) as well as scopolamine (0.5 mg/kg) and its combination with sildenafil (1.25 mg/kg) did not affect the total immobility time duration. However, joint administration of scopolamine with sildenafil at doses of 2.5 and 5 mg/kg significantly reduced immobility time as compared to control group. Moreover, co-administration of scopolamine with sildenafil at the highest dose (5 mg/kg) significantly decreased immobility time as compared to scopolamine-treated group. Sildenafil (1.25, 2.5 and 5 mg/kg) significantly enhanced the antidepressant activity of amitriptyline (5 mg/kg). No changes in anti-immobility action of desipramine (20 mg/kg) in combination with sildenafil (5, 10 and 20 mg/kg) were observed. Sildenafil did not affect amitriptyline level in both brain and serum. In conclusion, the present study suggests that sildenafil may enhance the activity of antidepressant drugs which exhibit cholinolytic activity.

Repeated antidepressant therapy increases cyclic GMP signaling in rat hippocampus

Cyclic adenosine monophosphpate (cAMP) signaling is thought to be involved in the pathophysiology of major depressive disorder and antidepressant action; however, relatively little is known about the possible role of cyclic guanosine monophosphate (cGMP) signaling. Accumulating evidence suggests that crosstalk occurs between cAMP and cGMP pathways. There is a need to clarify the trajectory of cAMP and cGMP concentrations, their synthesis by cyclases, and degradation by phosphodiesterases (PDEs) to understand the role of cyclic mononucleotide signaling in the effect of chronic antidepressant therapy. We used quantitative real-time PCR and enzyme immunoassay to systematically investigate the expression of intracellular signaling cascade elements in the hippocampus of rats chronically treated with the antidepressants fluoxetine and amitriptyline. We found increased cGMP levels, which were consistent with our findings of decreased PDE gene expression. Immunoassay results showed unchanged cAMP levels. We conclude that increased cGMP signaling might underlie the efficacy of chronic antidepressant treatment.

A multicenter, randomized, open-labeled, parallel group trial of sildenafil in alcohol-associated erectile dysfunction: the impact on psychosocial outcomes

To examine the effect of sildenafil on erectile dysfunction (ED) and psychosocial outcomes in alcohol-dependent (AD) men, 108 men with these diagnoses were randomly assigned to either take sildenafil (50 mg) as add-on to standard treatment for AD, or the same treatment without sildenafil, for 12 weeks. Only 50 patients in sildenafil group and 51 in control group twice completed the International Index of Erectile Function (IIEF) and a battery of self-report questionnaires. IIEF scores and psychosocial functioning, self-esteem and support from friends improved only for sildenafil-treated patients (P < 0.001). The high effect sizes suggest that the observed benefits are unlikely to be a placebo effect, although their unspecific nature could not be ruled out. In men with ED associated with AD, sildenafil improves both ED and psychosocial outcomes. Further placebo-controlled clinical trial is warranted.

Appearance of antidepressant-like effect by sildenafil in rats after central muscarinic receptor blockade: evidence from behavioural and neuro-receptor studies

The phosphodiesterase (PDE) 5 inhibitor sildenafil has been shown to display psychotropic actions in humans and animals, and has been used for the treatment of antidepressant-associated erectile dysfunction. However, its effects on the neurobiology of depression are unknown. Nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) inhibition is anti-depressant in animals, and increasing cGMP with sildenafil is anxiogenic in rodents. Substantial cholinergic-nitrergic interaction exists in the brain, while sildenafil shows modulatory actions on cholinergic transmission. Depression is also associated with increased cholinergic drive. Here we report that sildenafil increases muscarinic acetylcholine receptor (mAChR) signaling in human neuroblastoma cells. We also show that fluoxetine (20 mg/kg/day x 7 days), as well as a combination of sildenafil (10 mg/kg/day x 7 days) plus the antimuscarinic atropine (1 mg/kg/day x 7 days) demonstrates significant, comparable antidepressant-like effects in the rat forced swim test (FST) and also reduces cortical beta-adrenergic receptor (beta-AR) density, while sildenafil or atropine alone did not. Importantly, sildenafil did not modify fluoxetine's response. Sildenafil thus demonstrates antidepressant-like effects but only after central muscarinic receptor blockade, providing evidence for cholinergic-nitrergic interactions in the neurobiology of depression.

Correlations between increased erection hardness and improvements in emotional well-being and satisfaction outcomes in men treated with sildenafil citrate for erectile dysfunction

To explore relationships between erection hardness and other outcomes in men with erectile dysfunction (ED). Pooled analyses were conducted on 27 randomized, double-blind, placebo-controlled trials and six open-label trials from the worldwide sildenafil database. Outcomes included erection hardness graded subjectively, hardness and sexual satisfaction questions from the International Index of Erectile Function, general and sexually-specific emotional well-being from the self-esteem and relationship questionnaire, and the erectile dysfunction inventory of treatment satisfaction. Hardness outcomes improved (with a possible dose-response relationship for the achievement of fully hard and rigid erections) and correlated positively with the other outcomes. Sildenafil 100 mg produced optimal erection hardness (fully hard and rigid erections) in a substantial proportion of men with ED. Because optimal erection hardness correlated positively with some emotional well-being and satisfaction outcomes, sildenafil 100 mg may be the most appropriate dosage for treatment of ED for most men.

Tianeptine can be effective in men with depression and erectile dysfunction

INTRODUCTION

Erectile dysfunction (ED) and depression are highly prevalent medical disorders affecting men of diverse cultures throughout the world. Tianeptine is a new antidepressant drug with less adverse effects on sexual functions.

AIM

To evaluate the efficacy of tianeptine in the treatment of mild to moderate depression with ED.

METHODS AND MAIN OUTCOME MEASURES

A randomized, double-blind, placebo-controlled, crossover trial. Subjects were assigned either tianeptine or matching placebo, each for 8 weeks. All patients were followed up on monthly basis where they were asked to complete three assessment questionnaires, namely, Anxiety and Depression Scale, Brief Sexual Inventory, and Quality-of-life and erection questionnaire. All patients were asked a global assessment question. Treatment-responsive subjects were defined as study participants who had scores 1-16 on the Anxiety and depression Scale, showed normal erectile function on the Brief Sexual Inventory, and answered "yes" to the global assessment question.

RESULTS

Of the 237 consecutive men complaining of ED of >6 months and screened for this study, 110 patients met our inclusive criteria; 42 declined to participate. The remaining 68 patients were randomly assigned to treatment. Significant improvement (P < 0.05) was observed during the active drug phase in all three assessments questionnaires, in comparison with the placebo phase. Forty-eight patients (72.7%) of the subjects during the active drug phase were classified as responders, while 19 (27.9%) of the subjects during placebo phase were classified as responders.

CONCLUSIONS

Tianeptine could be considered an effective therapy for the treatment of depression and ED. Further large-scale multicentered studies are warranted.

Erectile function and assessments of erection hardness correlate positively with measures of emotional well-being, sexual satisfaction, and treatment satisfaction in men with erectile dysfunction treated with sildenafil citrate (Viagra)

We aimed to determine whether erectile function (EF) and assessments of erection hardness correlate positively with measures of psychosocial outcomes (ie, emotional well-being, sexual satisfaction, and satisfaction with erectile dysfunction [ED] treatment) in men treated with sildenafil citrate (Viagra; Pfizer Inc, New York, NY). Data were collected from 33 worldwide phase 2, 3, and 4 sildenafil clinical trials, which included almost 10,000 men with ED. Most of these trials were randomized, double-blind, and placebo-controlled (n = 27) and were undertaken to assess doses of 50 mg adjustable to 25 mg or 100 mg, depending on efficacy and tolerability (n = 32). Doses were taken approximately 1 hour before anticipated sexual activity but not more often than once daily. EF was assessed with use of the EF domain of the International Index of Erectile Function (IIEF) and with assessments of erection hardness (Erection Hardness Grading Scale [EHGS] and IIEF Q2 [the frequency of erections hard enough for penetration]). Change (baseline to end point) in emotional well-being in men treated for ED was assessed with the Self-Esteem and Relationship (SEAR) questionnaire, which consisted of the Confidence domain (ie, the Self-Esteem subscale and Overall Relationship subscale) and the Sexual Relationship domain. End point treatment satisfaction (overall, speed of onset, and duration of action) was assessed with the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS). The IIEF was used to assess change and end point sexual satisfaction by means of the Intercourse Satisfaction domain, Q7 (frequency of satisfactory sexual intercourse), and the Overall Satisfaction domain (ie, Q13, satisfaction with sex life, and Q14, satisfaction with sexual relationship). In men treated with sildenafil for ED, scores for measures of EF (IIEF EF domain, IIEF Q2) and the percentage of erections graded completely hard and fully rigid (EHGS grade 4) correlated positively with scores for measures of psychosocial outcomes (SEAR emotional well-being, IIEF sexual satisfaction, and EDITS ED treatment satisfaction), indicating that when EF improved and erection hardness increased, these measures of psychosocial function also improved.

Erection hardness: A unifying factor for defining response in the treatment of erectile dysfunction

The extensive sildenafil citrate erectile dysfunction (ED) database of double-blind, placebo-controlled clinical trials was examined to determine the relation between erection hardness graded on the Erectile Hardness Grading Scale (EHGS) and (1) erectile function (EF), as assessed by the EF domain of the International Index of Erectile Function (IIEF); (2) frequency of erections hard enough for penetration, as assessed by IIEF Q2; and (3) the percentage of successful sexual intercourse attempts according to patient event logs. Pooled data from 6549 men with ED provided strong proof and improved characterization of the response to sildenafil. Almost half of men with ED and a baseline IIEF EF domain score classified as "severe ED" (< or = 10) shifted to a score classified as "no ED" (> or = 26). Sildenafil recipients showed greater mean improvement from baseline to end point in IIEF Q2 scores versus placebo, regardless of baseline ED severity, and a higher mean percentage of successful sexual intercourse attempts occurred during the last 4 weeks of treatment versus placebo (5.4-fold vs 2.0-fold increase from baseline). At end point, 95% of men who scored "no ED" on the IIEF EF domain and 92% of men who reported "almost always/always" achieving an erection hard enough for penetration (IIEF Q2) had graded their erections hard (rigid) enough for penetration (grade 3) or completely hard and fully rigid (grade 4) during the last 4 weeks of treatment, suggesting that the IIEF EF domain and IIEF Q2 may be good surrogate end points for erection hardness. Furthermore, during the last 4 weeks of treatment, the percentage of grade 3 and/or 4 erections correlated positively with the percentage of successful sexual intercourse attempts. Hence, hard erections may be considered a unifying factor that defines response to ED treatment. Completely hard and fully rigid erections (grade 4) should be recognized as the optimal goal of an ED therapy. Evidence presented here demonstrates that sildenafil significantly improved EF as assessed by the IIEF EF domain and assessments of erection hardness in patients with ED; a dose-response relation was observed in the proportions of men with ED who graded their erections hard (rigid) enough for sexual penetration or completely hard and fully rigid.

Open-label sildenafil treatment of partial and non-responders to double-blind treatment in men with antidepressant-associated sexual dysfunction

Fifty partial and non-responders (Clinical Global Impression-Sexual Function (CGI-SF) score>2), out of 76 men who completed a 6-week, double-blind, placebo-controlled trial of sildenafil treatment for serotonergic antidepressant-associated sexual dysfunction, were eligible for an additional 6-week trial of open-label sildenafil (50 mg adjustable to 100 mg) under the same protocol, with blind maintained to initial assignment. Participation (double-blind and open-label) required major depressive disorder in remission (MDD-R) and continuing antidepressant medication. Forty-three entered open-label study: 16/17 initially randomized to sildenafil (sildenafil/sildenafil) and 27/33 initially randomized to placebo (placebo/sildenafil). Thirty-five of 43 (81%) achieved full response (CGI-SF<or=2): placebo/sildenafil 23/27 (85%); sildenafil/sildenafil 12/16 (75%); P<0.0001 for changes and P=0.4 between groups. Secondary measures of erectile function and overall satisfaction improved in both groups (P<0.03). Hamilton Depression Rating Scale scores improved (placebo/sildenafil; P<or=0.05) or remained stable (sildenafil/sildenafil). In men with MDD-R who maintained antidepressant adherence, 81% of double-blind partial and non-responders treated with open-label sildenafil responded fully.

Sildenafil citrate (Viagra) treatment for erectile dysfunction: An updated profile of response and effectiveness

In the 7 years since sildenafil citrate (VIAGRA) was introduced as the first oral phosphodiesterase type 5 inhibitor therapy for erectile dysfunction, it has been used to treat nearly 27 million men with erectile dysfunction worldwide. Patient populations with erectile dysfunction of varying etiologies and with diverse comorbidities have benefited from sildenafil treatment. This update focuses on relatively recent research that further defines the response and effectiveness profiles of sildenafil and provides additional insight into optimizing treatment. In addition to providing recent data on sildenafil efficacy and safety/tolerability, the update provides data on assessments of erection hardness, measures of psychosocial outcomes (e.g., emotional well-being and treatment satisfaction), and treatment approaches to maximize response and effectiveness (e.g., by titrating to the maximum tolerated dose). Increased understanding of the sildenafil response and effectiveness profiles and optimal sildenafil treatment are central to the appropriate management of erectile dysfunction using sildenafil.

Evaluation of erectile dysfunction therapy in patients previously nonadherent to long-term medications: a retrospective analysis of prescription claims

Erectile dysfunction (ED) can lead to treatment noncompliance in patients taking medications for chronic health conditions. Using the Intelligent Health Repository, NDCHealth's longitudinal, United States health care claims database, we examined the impact of treating ED on adherence to long-term therapies in previously nonadherent patients. Male patients >or=18 years of age were identified who received antidepressant (AD), antihypertensive (AH), oral hypoglycemic (OHG), or lipid-lowering (LL) agents and initiated therapy with sildenafil citrate (Viagra) between January and June 2003. Treatment adherence was determined using medication possession ratios (MPRs) for the 12 months before and after the first prescription of sildenafil. Prior to initiation of therapy for ED with sildenafil, 64% of patients with comorbid medications were not adherent (MPR <0.8). Among these patients, 728 (27%) received AD, 2112 (78%) received AH, 984 (18%) received OHG, and 1078 (40%) received LL agents, with 66% of patients receiving multiple therapeutic classes. During the 12-month period after the first sildenafil prescription, patients had a significant increase in medication adherence compared with the 12 months before the first prescription of sildenafil (P < 0.0001). The percentage of patients who became adherent (MPR >or=0.8) with medications after sildenafil treatment was from 22% to 36%. With the exception of the LL group, there was a significant relationship between >or=3 sildenafil prescriptions and change in MPR (P < 0.05). Patients aged >or=65 years had similar improvement in MPR as patients <or=65 years. Treatment of ED with sildenafil improved adherence in patients taking common long-term medications who were previously nonadherent.

Indirect comparison of interventions using published randomised trials: systematic review of PDE-5 inhibitors for erectile dysfunction

BACKGROUND

There are no randomised and properly blinded trials directly comparing one PDE-5 inhibitor with another in a normal home setting. Valid indirect comparisons with a common comparator must examine equivalent doses, similar duration, similar populations, with the same outcomes reported in the same way.

METHODS

Published randomised, double-blind trials of oral PDE-5 inhibitors for erectile dysfunction were sought from reference lists in previous reviews and electronic searching. Analyses of efficacy and harm were carried out for each treatment, and results compared where there was a common comparator and consistency of outcome reporting, using equivalent doses.

RESULTS

Analysis was limited by differential reporting of outcomes. Sildenafil trials were clinically and geographically more diverse. Tadalafil and vardenafil trials tended to use enriched enrollment. Using all trials, the three interventions were similar for consistently reported efficacy outcomes. Rates of successful intercourse for sildenafil, tadalafil and vardenafil were 65%, 62%, and 59%, with placebo rates of 23-28%. The rates of improved erections were 76%, 75% and 71%, respectively, with placebo rates of 22-24%, and NNTs of 1.9 or 2.0. Reporting of withdrawals was less consistent, but all-cause withdrawals for sildenafil, tadalafil and vardenafil were 8% 13% and 20%. All three drugs were well tolerated, with headache being the most commonly reported event at 13-17%. There were few serious adverse events.

CONCLUSION

There were differences between trials in outcomes reported, limiting comparisons, and the most useful outcomes were not reported. For common outcomes there was similar efficacy between PDE-5 inhibitors.

Strategies for managing antidepressant-induced sexual dysfunction: systematic review of randomised controlled trials

BACKGROUND

This review was undertaken to assess the effectiveness of management strategies for sexual dysfunction caused by antidepressant medication.

METHODS

Electronic databases and reference lists were searched, and pharmaceutical companies and experts contacted to identify randomised controlled trials comparing management strategies for antidepressant-induced sexual dysfunction.

RESULTS

Fifteen trials involving 904 people were included. One trial involving 75 people with sexual dysfunction due to sertraline assessed changing antidepressant. Switching to nefazodone was significantly less likely to result in the re-emergence of sexual dysfunction than restarting sertraline (RR 0.34, 95% CI 0.15 to 0.6). Meta-analysis of two trials involving 113 men with erectile dysfunction found that the addition of sildenafil resulted in less sexual dysfunction at endpoint on rating scales including the International Index of Erectile Function (IIEF) (WMD 19.36, 95% CI 15.00 to 23.72). Another trial found the addition of bupropion led to improved scores on the Changes in Sexual Functioning Questionnaire desire-frequency subscale (WMD 0.88, 95% CI 0.21 to 1.55). In a further study the addition of tadalafil was associated with greater improvement in the erectile function domain of the IIEF than placebo (WMD 8.10; 95% CI 4.62 to 11.68). Other augmentation strategies failed to show statistically significant improvements in sexual dysfunction compared with placebo.

DISCUSSION

The currently available evidence is rather limited, with small numbers of trials assessing each strategy. However, while further randomised data is awaited, for men with antidepressant-induced erectile dysfunction, the addition of sildenafil appears to be an effective strategy.

Strategies for managing sexual dysfunction induced by antidepressant medication

BACKGROUND

Sexual dysfunction (including altered desire, orgasmic dysfunction, erectile and ejaculatory problems) is a relatively common side effect of antidepressant medication. These sexual side effects may compromise a person's lifestyle and result in a lack of compliance with the prescribed antidepressant to the detriment of the person's mental health.

OBJECTIVES

The objective of this review was to assess the effectiveness of management strategies for sexual dysfunction caused by antidepressant medication.

SEARCH STRATEGY

We searched the CCDANCTR (March 2003), the Cochrane Central Register of Controlled Trials (Cochrane Library issue 2, 2004), MEDLINE (1966 - June 2004), EMBASE (1980 - March 2004), CINAHL (1982 - March 2004), PsycINFO (1984 - March 2004) and the reference lists of articles. We also contacted pharmaceutical companies and experts in the field of sexology.

SELECTION CRITERIA

Randomised controlled trials comparing the management strategies for antidepressant induced sexual dysfunction were included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed trial quality. Study authors were contacted for additional information. Adverse effect information was collected from the trials.

MAIN RESULTS

Fifteen trials involving 904 people were included. One trial involving 75 people with sexual dysfunction due to sertraline assessed changing antidepressant. Switching to nefazodone was significantly less likely to result in the re-emergence of sexual dysfunction than restarting sertraline (RR 0.34, 95% CI 0.15 - 0.6) and was not associated with any worsening of depression. Fourteen trials involving 829 people assessed the addition of other medication while continuing the same antidepressant. Meta-analysis of two trials involving 113 men with erectile dysfunction found that the addition of sildenafil resulted in less sexual dysfunction at endpoint on rating scales including the International Index of Erectile Function (IIEF; WMD 19.36, 95% CI 15.00 to 23.72). There was no significant difference in dropout rates between sildenafil and placebo. One trial found the addition of bupropion led to improved scores on the Changes in Sexual Functioning Questionnaire desire-frequency subscale (WMD 0.88, 95% CI 0.21 - 1.55). One trial found that the addition of tadalafil was associated with greater improvement in the erectile function domain of the IIEF than placebo (WMD 8.10; 95% CI 4.62 to 11.68). Other augmentation strategies failed to show statistically significant improvements in sexual dysfunction compared with placebo.

REVIEWERS' CONCLUSIONS

The currently available evidence is rather limited, with small numbers of trials assessing each strategy. However, while further randomised data is awaited, for men with antidepressant-induced erectile dysfunction, the addition of sildenafil appears to be an effective strategy.