Evaluation of the effectiveness of sildenafil using questionnaire methods versus audio-visual sexual stimulation

AIM: In the present study, an audio-visual sexual stimulation (AVSS) test was used to evaluate the effectiveness of sildenafil, and the AVSS test was coevaluated with the international index of erectile function (IIEF) questionnaire. METHODS: Forty-two patients with erectile dysfunction (ED) were examined (age range, 28-73 years; mean, 51.9 +/- 11.4 years). Each patient answered the IIEF questionnaire and underwent laboratory tests and the AVSS test before administration of sildenafil. The IIEF questionnaire and AVSS test (1 h after administration of 25 mg or 50 mg sildenafil) were re-evaluated in the outpatient clinic 4 weeks later. Questions 3 and 4 of the IIEF test were used to evaluate the effectiveness of sildenafil. Sildenafil was determined to be effective if each score totalled four or five after administration. RESULTS: The rate of effectiveness of sildenafil was 52.4%, and the mean score of the IIEF 5 improved from 7.2 to 15.4 following treatment with sildenafil. The maximum and mean rigidity of the penile tip improved after the sildenafil treatment (36.1%vs 57.7% and 14.2%vs 35.8%, respectively). The maximum and mean rigidity of the penile base rose (42.4%vs 57.7% and 17.9%vs 36.8, respectively). Similarly, following treatment with sildenafil, the penile tumescence increased from 6.6 cm to 7.6 cm at the penile tip and from 7.5 cm to 8.5 cm at the penile base. CONCLUSIONS: In some ED patients the results of the IIEF questionnaire are not always consistent with those of objective evaluation, including AVSS. In these patients, combined assessment using the IIEF and AVSS might be more useful to evaluate the precise effectiveness of sildenafil, rather than relying on the IIEF results alone.     

Role of sildenafil citrate in treatment of erectile dysfunction after radical retropubic prostatectomy

BACKGROUND: Sildenafil citrate was introduced as a treatment for erectile dysfunction in April 1998 in the United States and has been available since March 1999 in Japan. In this article, we assess the efficacy of sildenafil in the treatment of erectile dysfunction in Japanese men after radical retropubic prostatectomy for localized prostate cancer. METHODS: Of 106 men who underwent radical retropubic prostatectomy between January 1994 and March 2000, 43 were prescribed sildenafil at their request after radical retropubic prostatectomy. Medication was initiated at 25 mg, and if this was ineffective, the dose was increased to 50 mg. Of the patients, 18 underwent bilateral and 21 unilateral nerve sparing (NS) procedures, while in 4 patients, a non-NS procedure was performed. These patients were interviewed using a questionnaire about their response to sildenafil and using the 5-item International Index of Erectile Function (IIEF-5) questionnaire. RESULTS: Thirty-three of the 43 patients were eligible for evaluation of the efficacy of sildenafil and 27 completed the IIEF-5 questionnaires. Sildenafil at 50 mg had a better effect on sexual function than 25 mg in most Japanese patients. Of the 16 patients who underwent bilateral NS procedures, 10 (62.5%) had improved ability for intercourse and 3 (18.8%) had improved erections. Of the 13 patients who underwent unilateral NS procedures, 7 (53.8%) had improved ability for intercourse and 4 (30.8%) had improved erections. None of the 4 patients who underwent non-NS procedures had a positive response. Of 24 patients with positive response to sildenafil, 3 (12.5%) did not have to take sildenafil after receiving it because they did not require it for intercourse. Mean IIEF-5 score increased from 4.3 to 11.4 (P < 0.0001). Patient age, time since surgery, PSA and pathological stage did not have statistically significant effects on outcome. The most commonly cited adverse effect was headache (21%). CONCLUSION: Sildenafil is equally effective for erectile dysfunction in Japanese patients who have undergone bilateral and unilateral NS procedures, and aids recovery of natural erectile function after radical retropubic prostatectomy. However, non-NS procedure patients had no response to sildenafil. This study suggested that sildenafil is well tolerated and should be initially used for treatment of Japanese men with erectile dysfunction after radical retropubic prostatectomy.     

Clinical application of prognostic factors for patients with organic causes of erectile dysfunction on 100 mg of sildenafil citrate

OBJECTIVES: There are still no clinical predictive factors to determine the response rate of erectile dysfunction (ED) patients to sildenefil citrate. The aim of the present study is to evaluate and stratify the risk factors and attempted to determine the prognostic factors in clinical practice to predict the response rate. This is important in improving cost effectiveness and avoiding side-effects. MATERIAL AND METHODS: This is an open label prospective study including patients attending the andrology clinic in Tan Tock Seng Hospital, Singapore, over 2 years. The patients were evaluated and investigated for possible underlying causes and ED severity was assessed by five-items of the International Index of Erectile Function questionnaire (IIEF-5), together with the duration, degree and rigidity of erection. Psychogenic causes were excluded with a minimal follow up of 6 months. All patients were placed on 100 mg of sildenafil citrate and were reassessed at the end of 6 months. Logistic regression with univariate and multivariate was used as the method of statistical analysis. RESULTS: A total of 232 patients were in the cohort. The overall response rate was 43%, with the best response rate in veno-occlusive cases and the worst responses from neurogenic causes. Age, smoking, diabetes mellitus, hypertension, hyperlipidemia, pretreatment IIEF-5 score, interval to achieve erection and duration of erection were significant in univariate analysis, but only age, smoking and IIEF-5 score were significant in multivariate analysis. With a combination of these factors, a table was formed to determine the possible response rate in clinical practice. This will assist physicians in selecting patients with potentially favorable responses and avoid side-effects and an unnecessary wastage of time and cost. CONCLUSION: Possible factors could be determined and used clinically to predict the response rate to sildenafil citrate.     

Development and characterization of polymer-coated liposomes for vaginal delivery of sildenafil citrate

Vaginal administration of sildenafil citrate has shown recently to develop efficiently the uterine lining with subsequent successful embryo implantation following in vitro fertilization. The aim of the present study was to develop sildenafil-loaded liposomes coated with bioadhesive polymers for enhanced vaginal retention and improved drug permeation. Three liposomal formulae were prepared by thin-film method using different phospholipid:cholesterol ratios. The optimal liposomal formulation was coated with bioadhesive polymers (chitosan and HPMC). A marked increase in liposomal size and zeta potential was observed for all coated liposomal formulations. HPMC-coated liposomes showed the greater bioadhesion and higher entrapment efficiency than chitosan-coated formulae. The in vitro release studies showed prolonged release of sildenafil from coated liposomes as compared to uncoated liposomes and sildenafil solution. Ex vivo permeation study revealed the enhanced permeation of coated relative to uncoated liposomes. Chitosan-coated formula demonstrated highest drug permeation and was thus selected for further investigations. Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR) confirmed the successful coating of the liposomes by chitosan. Histopathological in vivo testing proved the efficacy of chitosan-coated liposomes to improve blood flow to the vaginal endometrium and to increase endometrial thickness. Chitosan-coated liposomes can be considered as potential novel drug delivery system intended for the vaginal administration of sildenafil, which would prolong system's retention at the vaginal site and enhance the permeation of sildenafil to uterine blood circulation.     

Medical expulsive therapy in urolithiasis: a mixed treatment comparison network meta-analysis of randomized controlled clinical trials

Background: Medical expulsive therapy (MET) using alpha blockers, calcium channel blockers (CCB), phosphodiesterase inhibitors (PDEI) and spasmolytics have been shown to be effective in clinical trials on urolithiasis. The present study is a network meta-analysis comparing the above mentioned drug classes.

Research design and methods: Electronic databases were searched for randomized controlled trials comparing the above mentioned drug classes in patients with urolithiasis using appropriate search strategy. Inverse variance heterogeneity model was used for the mixed treatment comparisons. Stone expulsion rate (SER) was the primary and stone expulsion time (SET) was the main secondary outcome measure.

Results: We included a total of 114 studies for systematic review and 108 studies for the network meta-analysis. Alpha blockers, PDEI, and combined alpha blockers and corticosteroids had significantly increased SER and shorter SET than placebo or standard of care. Alpha blockers have the highest probability of being the ‘best’ in the pool with regard to SER. This effect persisted in patients with stones ≥ 5 mm, children, after shockwave lithotripsy, proximal ureteric stones and distal ureteric stones.

Conclusion: To conclude, we observed a statistically significant increase in the expulsion rate and shorter expulsion time with alpha blockers, PDEI and combined alpha blockers with corticosteroids. Of these interventions, alpha blockers have the high probability of being the ‘best’.     

Comparison of the effects of systemic sildenafil,tadalafil, and vardenafil treatments on skin flap survival in rats

Abstract

Objective: The most important issue in flap surgery is flap viability. This study aimed to compare the effects of most commonly used phosphodiesterase type 5 (PDE5) inhibitors on flap survival. Methods: A 3 × 9 cm flap was elevated from the dorsum of 32 Wistar albino rats. In the control group, saline was administered 2 hours before the flap elevation and continued for 2 days after the surgery. In the sildenafil, tadalafil, and vardenafil groups, the related drug was administered. Blood flow in the flaps was monitored with laser Doppler flowmetry. On postoperative day 7, flaps were photographed and biopsies were obtained. Results: The ratios of flap necrosis area in the tadalafil, sildenafil, and vardenafil groups were lower than that in the control group, but without significant difference (p = 0.077). Histopathological evaluation revealed no significant difference among the groups. Conclusion: The ratio of flap necrosis area tended to be lower in the groups receiving oral PDE5 inhibitors than in the control group, although not statistically significant. The role of PDE5 inhibitors needs to be evaluated in larger studies before a conclusion can be made regarding their effects on flap viability.     

西地那非对高原人体运动血乳酸及自由基代谢的影响

目的：探讨西地那非对高原人体运动血乳酸及自由基代谢的影响。方法：在海拔3700 m选择10名已习服半年的男性士兵,在海拔5380 m选择10名已习服2个月的男性士兵,均采用服药前（对照组）后（实验组）的自身对比运动负荷双盲实验。运动结束检测血中超氧化物歧化酶（SOD）、丙二醛（MDA）、乳酸（BLA）、尿素氮（BUN）、一氧化氮（NO）及其合酶（NOS）的含量。结果：海拔3700 m和5380 m负荷运动,实验组较对照组SOD、NO和NOS增高（P〈0.01）;MDA、BLA、BUN降低（P〈0.01或0.05）。结论：西地那非可提高高原人体作业效率,具有增强机体抗疲劳和抗氧化的能力。