Screening impotence by home nocturnal tumescence self-monitoring

Sexual Dysfunction in Diabetic Patients: Τhe Role of Advanced Glycation End Products

Sexual dysfunction is a common but underestimated disorder of diabetic patients of both genders, entailing specific and complex pathogenesis and severely affecting reproductive health and quality of life. Hyperglycemia, dyslipidemia, hypertension, obesity, aging, and psychological factors underlie its pathogenesis. A large body of evidence indicates that advanced glycation end products and oxidative stress have a distinct impact on the pathogenesis of diabetes and its complications, including hypogonadism, which is closely related to sexual dysfunction. Advanced glycation end products seem to affect sexual function either directly by accumulation in various regions of the reproductive system and/or correlation or indirectly through oxidative stress induction via several mechanisms. They are also involved in the pathogenesis of diabetic complications, which are related to sexual dysfunction. Herein, we review the issue of sexual dysfunction in diabetic males and females, with special emphasis on the impact of advanced glycation end products in the pathogenesis of sexual dysfunction, the relationship of advanced glycation end products with low testosterone levels in diabetic subjects, which account for the proportion of disorder and the available therapeutic interventions.

Consecutive nightly measurements are needed for accurate evaluation of nocturnal erectile capacity when the first-night laboratory recording is abnormal

Multiple measurements of nocturnal penile tumescence and rigidity (NPTR) are widely accepted as a method to differentiate psychogenic erectile dysfunction (ED) from organic ED. However, direct evidence remains limited regarding the first-night effect on NPTR measurement using the RigiScan. Here, we evaluated the first-night effect on the results of NPTR measurement to validate the necessity of NPTR measurement for two consecutive nights, particularly when abnormal first-night measurements are recorded in a laboratory setting. We retrospectively reviewed 105 patients with a complaint of ED, who underwent NPTR measurement using the RigiScan in the Department of Infertility and Sexual Medicine, the Third Affiliated Hospital of Sun Yat-sen University (Guangzhou, China), for two consecutive nights, during the period from November 2015 to May 2016. NPTR parameters were collected and analyzed. We found that more effective nocturnal erections were detected during the second night than during the first night (P <0.001). Twenty percent of all patients had no effective erection during the first night, but exhibited at least one effective erection during the second night. The negative predictive value of NPTR measurement during the first night was 43.2%; this was significantly lower than that on the second night (84.2%; P = 0.003). Most NPTR parameters were better on the second night than on the first night. The first-night effect might be greater among patients younger than 40 years of age. In conclusion, two consecutive nightly measurements of NPTR can avoid a false-abnormal result caused by the first-night effect; moreover, these measurements more accurately reflect erectile capacity, especially when the first-night record is abnormal in a laboratory setting.

'Potency': the validation of information from a self-administered questionnaire using objective measurements of night-time erections and test-retest reliability

OBJECTIVE

To assess the validity and reliability of a questionnaire assessing 'physiological potency'.

PATIENTS AND METHODS

The study comprised 89 patients with prostate cancer and 43 men without; the latter were attending a consultation clinic because of problems with erection. All men answered three questions assessing erectile rigidity during sexual activity, morning and spontaneous erections. In the questionnaire, 'potency' was defined as erectile rigidity 'sufficient for intercourse most of the time' or better. 'Potency' in one or more of the three aspects of erection was defined as 'physiological potency'. The patients with prostate cancer answered the questionnaire twice with a 3-week interval. The men attending the consultation clinic underwent two nights of erectile monitoring (using the RigiScan device) and the minimum criterion for RigiScan potency was defined as 55% rigidity at both tip and base.

RESULTS

The test-retest assessment showed 93% conformity in the questionnaire diagnosis of 'physiological potency/impotence' between the tests. The sensitivity and specificity of the questionnaire assessment compared with the RigiScan method were 40% and 100%, respectively, when the question assessing sexually stimulated erectile rigidity was used alone. Using 'physiological potency', the sensitivity increased to about 60% without jeopardizing the specificity, and when men reporting depression were excluded from the analysis, the sensitivity increased to about 80%.

CONCLUSIONS

The test-retest reliability of the questionnaire was satisfactory. Using questions in a self-administered questionnaire, 'physiological impotence' can be diagnosed with complete and 'physiological potency' with 60-80% sensitivity. The sensitivity of the self-assessment for 'potency' depended on the number of questions asked and the proportion of men reporting depression.

Comparison of results of nocturnal penile tumescence and rigidity in a sleep laboratory versus a portable home monitor

OBJECTIVES

To validate the results of the home penile tumescence monitor versus the sleep laboratory studies of erectile function.

METHODS

We used both methods to study 18 episodes of rigidity and 19 episodes of tumescence in 10 subjects with erectile dysfunction before and after the use of an experimental vasodilating medication.

RESULTS

The tumescence measurement in the sleep laboratory compared favorably with the changes in tumescence with the RigiScan portable home monitor: at the base (r = 0.70; P < 0.001), and at the tip (r = 0.84; P < 0.001). In measuring rigidity, the buckling pressure in the sleep laboratory compared favorably with the RigiScan measurements of percent average rigidity at the base (r = 0.56; P = 0.017), at the tip (r = 0.62; P = 0.006), and mean rigidity of the base and tip (r = 0.64; P = 0.004). In a comparison of the buckling pressure with the new RigiScan Plus quantitative program, there was good correlation with the rigidity activity units at the base (r = 0.70; P = 0.001) and at the tip (r = 0.72; P < 0.001). A clinical estimate of penetrable rigidity correlates with the RigiScan base rigidity of 55% to 60% and tip rigidity of about 50%.

CONCLUSIONS

The portable home monitor is a viable and cost-effective clinical tool to measure nocturnal penile activity.

Comparison of RigiScan and formal nocturnal penile tumescence testing in the evaluation of erectile rigidity

Evaluation of male erectile function ideally should include measurement of axial rigidity expressed as grams force required to produce penile buckling. An axial rigidity more than 550 gm. is generally considered adequate for vaginal penetration. Unfortunately, this test cannot be done frequently and may disrupt sleep. An alternative method of determining rigidity is to use the RigiScan,* which makes repetitive measurements of radial rigidity at the base and tip of the penis expressed as per cent of normal maximum. Previous studies have demonstrated a positive correlation between axial and radial rigidity measurements but they have not been compared in patients with a wide range of erectile function. We performed a prospective study in a consecutive series of patients presenting with impotence comparing axial rigidity measured with a tonometer and radial rigidity measured by RigiScan. Erectile rigidity also was evaluated by a trained, blinded observer. Overall, RigiScan base and tip radial rigidity correlated well with axial rigidity (p < 0.002) and observer ratings (p < 0.003); axial rigidity similarly correlated well with observer ratings (p < 0.0001). However, when RigiScan base and tip radial rigidity exceeded 60% of maximum, there was a poor correlation with axial rigidity and observer ratings (p > 0.1). In this range, the RigiScan failed to discriminate axial rigidities between 450 and 900 gm. buckling force; however, axial rigidity in this same range again correlated well with observer ratings (p < 0.0001). Since an axial rigidity of more than 550 gm. is considered adequate for vaginal penetration, the RigiScan may not be able to detect mild abnormalities in erectile function. Further study is in progress to evaluate the significance of these findings but presently a RigiScan measurement of radial rigidity in excess of 60% of maximum should be interpreted cautiously and not necessarily regarded as normal. In this range further measurements of axial rigidity or observer ratings of rigidity may be necessary to establish the diagnosis.