Erectile dysfunction: interrelationship with the metabolic syndrome

Subclinical inflammation as a predictor for erectile dysfunction after brachytherapy for localized prostate cancer

PURPOSE

Neutrophil-to-lymphocyte ratio (NLR), a marker for subclinical inflammation, has been previously shown to be associated with erectile dysfunction (ED). We studied the potential predictive value of the NLR on ED after prostate brachytherapy (PB) for PCa.

METHODS AND MATERIALS

Between July 2005 and January 2021, 842 patients were included in this retrospective study of a prospectively maintained database. ED was assessed using the Common Terminology Criteria for Adverse Events (CTCAE) physician-reported scale. ED was defined as a Grade 2 or 3 function. NLR count was determined 1-2 months before PB and separated into values PB <2 and ≥2. Patient characteristics and erectile function at last follow-up were compared for patients with a Univariate and multivariate analyses were performed to evaluate the predictive value of baseline NLR ≥2 on post-PB ED.

RESULTS

Baseline NLR ≥2 was found to be a statistically significant predictor of post-PB ED on both univariate (p = 0.002) and multivariate analyses (p = 0.008). Furthermore, the difference in ED prevalence between the NLR <2 and NLR ≥2 groups became more pronounced with longer follow-up after PB. The ED rate at 5 years post-PB was 43% for the NLR ≥2 groups, compared to 29% for the NLR <2 groups.

CONCLUSIONS

Subclinical systemic inflammation is a potentially important factor for predicting sexual toxicity after pelvic radiotherapy. NLR may be used as a proxy for predicting post-PB ED.

Diagnostic work up: Laboratory and biomarkers

This chapter will focus on the diagnostic work around sexual dysfunction in Parkinson's disease, especially laboratory tests and biomarkers. A number of methods to analyze if sexual dysfunction is caused by neural pathology, vascular dysfunction or other mechanisms are now available. Other methods can be used to differentiate between psychogenic/functional reasons behind sexual dysfunction and organic ones. The role of biomarkers for diagnosis, but also for understanding the reason behind and for counteracting sexual dysfunction is becoming more evident. There is also a rich and increasing number of scales and other instruments available for detecting and quantifying sexual hypo- and hyperactivity. When investigating the reason behind sexual dysfunction in patients with Parkinson's disease comorbidities should also be considered. Finally, early and pronounced sexual dysfunction might in some cases be an indication that differential diagnosis, like Multisystem Atrophy, should be thought about. All these aspects of the diagnostic procedures around sexual dysfunction in Parkinson's disease will be covered in this chapter.

Identification of miRNA Signature Associated With Erectile Dysfunction in Type 2 Diabetes Mellitus by Support Vector Machine-Recursive Feature Elimination

Diabetic mellitus erectile dysfunction (DMED) is one of the most common complications of diabetes mellitus (DM), which seriously affects the self-esteem and quality of life of diabetics. MicroRNAs (miRNAs) are endogenous non-coding RNAs whose expression levels can affect multiple cellular processes. Many pieces of studies have demonstrated that miRNA plays a role in the occurrence and development of DMED. However, the exact mechanism of this process is unclear. Hence, we apply miRNA sequencing from blood samples of 10 DMED patients and 10 DM controls to study the mechanisms of miRNA interactions in DMED patients. Firstly, we found four characteristic miRNAs as signature by the SVM-RFE method (hsa-let-7E-5p, hsa-miR-30 days-5p, hsa-miR-199b-5p, and hsa-miR-342–3p), called DMEDSig-4. Subsequently, we correlated DMEDSig-4 with clinical factors and further verified the ability of these miRNAs to classify samples. Finally, we functionally verified the relationship between DMEDSig-4 and DMED by pathway enrichment analysis of miRNA and its target genes. In brief, our study found four key miRNAs, which may be the key influencing factors of DMED. Meanwhile, the DMEDSig-4 could help in the development of new therapies for DMED.

Serum Biomarkers of Erectile Dysfunction in Diabetes Mellitus: A Systematic Review of Current Literature

INTRODUCTION

Erectile dysfunction (ED) is a common complication in patients with diabetes mellitus (DM). However, the utility of serum biomarkers as clinical surrogates for the development and/or progression of ED is unknown.

AIM

To summarize the current literature for serum biomarkers for ED in DM and emphasize areas for future research.

MAIN OUTCOME MEASURES

Human subject data demonstrating the utility of serum markers for the development and progression of ED in patients with DM.

METHODS

We performed a systematic PubMed-Medline search in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement using Medical Subject Headings (MeSH) for articles published from January 1, 2000 through December 31, 2016 of serum biomarkers for development or progression of ED in patients with DM using erectile dysfunction [MeSH] AND (biomarkers [MeSH] or inflammation mediators [MeSH] or intercellular signaling peptides and proteins [MeSH] or cell adhesion molecules [MeSH]). A thorough review of these studies was completed.

RESULTS

Of the 327 abstracts screened, 12 full-text studies were assessed and 1 study was excluded. Eleven studies assessing serum biomarkers for ED in patients with DM were included in this review. The most studied serum biomarkers for ED in men with DM included endothelial dysfunction markers such as serum E-selectin, endothelial progenitor cells, and endothelial microparticles and specific markers of inflammation such as interleukin-10, ratio of tumor necrosis factor-α to interleukin-10, and reactive oxygen species such as nitric oxide and malondialdehyde. Reliable serum biomarkers will enable earlier diagnosis and objective monitoring of disease progression and responses to treatment in patients with ED.

CONCLUSION

Serum biomarkers for ED in men with DM are very limited. Future longitudinal studies with uniform patient characteristics are needed to evaluate the potential clinical use of serum biomarkers in men with DM for the development and progression of ED. Patel DP, Craig JR, Myers JB, et al. Serum Biomarkers of Erectile Dysfunction in Diabetes Mellitus: A Systematic Review of Current Literature. Sex Med Rev 2017:5:339-348.

The impact of poor glycaemic control on the prevalence of erectile dysfunction in men with type 2 diabetes mellitus: a systematic review

Objective

To determine the impact of poor glycaemic control on the prevalence of erectile dysfunction among men with type 2 Diabetics aged 27 to 85 years.

Design

The databases Embase classic+Embase, Global health, Ovid Medline and PsychINFO, were searched for relevant studies in June 2014 using the keywords: (Diabetes Mellitus OR diabetes mellitus type2 OR DM2 OR T2DM OR insulin resistance) AND (erectile dysfunction OR sexual dysfunction OR impotence) AND glycaemic control.

Setting

All study settings were considered (primary care, secondary care and tertiary care setting).

Participants

Type 2 Diabetic Patients with erectile dysfunction.

Main outcome measures

Included studies must include one of the following outcomes: (1) HBA1c for assess the level of glycaemic control; (2) Erectile dysfunction (any stage: IIEF-5 = 21 or less).

Results

Five cross-sectional studies involving 3299 patients were included. The findings pointed to a positive association between erectile dysfunction and glycaemic control. Three studies showed a significant positive association, while one study showed only a weak correlation and one study showed borderline significance. Patients’ age, diabetes mellitus duration, peripheral neuropathy and body mass index had positive association with erectile dysfunction. However, smoking and hypertension were not associated with erectile dysfunction in most included studies. Physical activity had a protective effect against erectile dysfunction.

Conclusion

We may conclude that the risk of erectile dysfunction is higher in type 2 diabetic men with poor glycaemic control than those with good control.

The effect of lifestyle modification and glycemic control on the efficiency of sildenafil citrate in patients with erectile dysfunction due to type-2 diabetes mellitus

OBJECTIVES

We evaluated the effect of lifestyle modifications and glycemic control on the efficiency of sildenafil citrate in patients with type-2 diabetes (T2DM) and erectile dysfunction (ED).

METHODS

Eighty-three men with ED due to T2DM were included in the study. The Group 1 (n = 41) patients received lifestyle modifications (diet and exercise), and medical treatment for intensive glycemic control. In Group 2 (n = 42), in addition to the intensive glycemic control, the patients were given sildenafil citrate® 100 mg for 2-3 per weeks. The changes in ED were compared between the two groups after three months of treatment.

RESULTS

The mean age was 54.9 ± 9.1 (26-75) years. An increase in the IIEF-5 scores was observed in 23 of 41 patients in Group 1 (44.2%) and 29 of 42 in Group 2 (55.8%). When the changes of the IIEF-5 scores were evaluated, the mean increase was 2.5 in Group 1, and 5.0 in Group 2 (p = 0.012). The mean IIEF changes according to the duration of diabetes were 4.8 in <5 years, 3.6 in 5-10 years and 1.6 in >10 years (p = 0.021).

CONCLUSIONS

Glycemic control and lifestyle changes are not solely adequate for a better sexual function in ED due to diabetes, and sildenafil citrate should be used additionally.

Markers of erectile dysfunction

With the development and marketing of oral pharmacotherapy that is both noninvasive and successful in treating erectile dysfunction (ED), the quest to identify markers of organic ED lost ground. Indeed, the multi-factorial nature of ED may have led many researchers to conclude that searching for a universal marker of ED was futile. However, the realization that ED is strongly correlated with the overall health of men, and may act as a predictor for the development of cardiovascular disease (CVD) and diabetes, has stimulated interest in identifying genes that can distinguish organic ED. In addition, the potential ability to suggest to the patient that ED is reversible (i.e., psychogenic) with a simple test would be of significance to both the physician and patient, as well as for reimbursement issues for therapy by insurance companies. Such a marker may also act as a non-subjective measure of the degree of ED and the efficacy of treatment. This review discusses the importance of identifying such markers and recent work identifying potential markers in human patients.

Erectile dysfunction as a predictor for subsequent atherosclerotic cardiovascular events: findings from a linked-data study

INTRODUCTION

In spite of the mounting interest in the nexus between erectile dysfunction (ED) and cardiovascular (CV) diseases, there is little published information on the role of ED as a predictor for subsequent CV events.

AIM

This study aimed to investigate the role of ED as a predictor for atherosclerotic CV events subsequent to the manifestation of ED. Method. The investigation involved the retrospective study of data on a cohort of men with ED linked to hospital morbidity data and death registrations. By using the linked data, the incidence rates of atherosclerotic CV events subsequent to the manifestation of ED were estimated in men with ED and no atherosclerotic CV disease reported prior to the manifestation of ED. The risk of subsequent atherosclerotic CV events in men with ED was assessed by comparing these incidence rates with those in the general male population.

MAIN OUTCOME MEASURE

Standardized incidence rate ratio (SIRR), comparing the incidence of atherosclerotic CV events subsequent to the manifestation of ED in a cohort of 1,660 men with ED to the incidence in the general male population.

RESULTS

On the basis of hospital admissions and death registrations, men with ED had a statistically significantly higher incidence of atherosclerotic CV events (SIRR 2.2; 95% confidence interval 1.9, 2.4). There were significantly increased incidence rate ratios in all age groups younger than 70 years, with a statistically highly significant downward trend with increase of age (P < 0.0001) across these age groups. Younger age at first manifestation of ED, cigarette smoking, presence of comorbidities and socioeconomic disadvantage were all associated with higher hazard ratios for subsequent atherosclerotic CV events.

CONCLUSIONS

The findings show that ED is not only significantly associated with but is also strongly predictive of subsequent atherosclerotic CV events. This is even more striking when ED presents at a younger age.

Reversal of voltage-dependent erectile responses in the Zucker obese-diabetic rat by rosuvastatin-altered RhoA/Rho-kinase signaling

INTRODUCTION

The combination of independent risk factors for erectile dysfunction, obesity, hypertension, and diabetes are collectively manifested in a condition known as metabolic syndrome X (MSX). However, the regulatory mechanisms responsible for the erectile dysfunction (ED) are not fully understood. Clinical studies suggest that a pleiotropic effect of statin's ability to enhance vascular relaxation might be through an impact on nitric oxide signaling or through a regulation of RhoA activation.

AIM

We hypothesized that regulatory aspects of short-term statin therapy involve the alteration of the RhoA/Rho-kinase signaling cascade and will reverse the ED seen in a rat model of MSX.

MAIN OUTCOME MEASURES

The magnitude and sensitivity of the voltage-dependent maintenance of intracavernosal blood pressure and mean arterial blood pressure. These responses were correlated with tissue protein and mRNA expression levels of RhoA and Rho kinases.

METHODS

Erectile function was evaluated by assessing voltage-dependent stimulation of the cavernosal nerve in 16-20 weeks old lean and obese-diabetic Zucker rats treated with 5 mg/kg/day of rosuvastatin intraperitoneally for 3 days. Cavernosal tissue RhoA and Rho-kinases expression levels were evaluated by real-time reverse transcriptase-polymerase chain reaction, Western blot.

RESULTS

The voltage-dependent erectile responses were suppressed by >30% in the obese-diabetic Zucker rat. The 3-day treatment with rosuvastatin partially restored the erectile response. The Rho-kinase inhibitor, H-1152, dose dependently increased the erectile responses and shifted the voltage sensitivity with statin treatment. Analysis of protein expression levels suggested elevation of RhoA and Rho kinases in obese-diabetics and statin treatment lowering Rho-kinase II. The RhoA and Rho-kinase II mRNA levels were significantly reduced in the rosuvastatin-treated obese-diabetic animals.

CONCLUSIONS

These results support a hypothesis that short-term statin therapy may lower RhoA/Rho-kinase expression levels and improve cavernosal blood pressure response to Rho-kinase inhibition and voltage-stimulation, and reversing an augmented vasoconstricted state associated with diabetes and/or hypertension in MSX.

The burden and extent of comorbid conditions in patients with erectile dysfunction

BACKGROUND

Erectile dysfunction (ED) is a common sexual problem in men. Under-reporting of ED is widespread, largely because of the embarrassing nature of the condition.

AIM

This paper reviews the comorbid conditions that are commonly found in patients with ED patients and discusses the implications.

DISCUSSION

Erectile dysfunction is often associated with other disorders such as diabetes, cardiovascular disease, hypertension, dyslipidaemia, obesity, depression, chronic obstructive pulmonary disease and lower urinary tract symptoms. Although the aetiology of ED is multifactorial, some of the associated comorbid conditions, including diabetes, cardiovascular disease and hypertension, can be a primary cause of ED. Similarly, ED could be a useful marker for comorbid conditions such as cardiovascular disease and diabetes. Effective treatments for ED are available, including the three phosphodiesterase type 5 inhibitors sildenafil citrate, tadalafil and vardenafil HCl.

CONCLUSIONS

Thorough medical screening of patients with ED is advisable, as this could lead to earlier diagnosis and treatment of comorbid conditions. Conversely, men with conditions such as cardiovascular disease, diabetes, obesity and depression may have undiagnosed ED and should be questioned appropriately to ascertain any erectile problems and initiate appropriate treatment.

Sexual function and obesity

OBJECTIVE

To review the literature on the relationship between obesity and sexual function.

METHOD

A search in the medical literature from 1966 and onwards was carried out through Medline and Embase for publications on obesity, in combination with Medical Subject Heading words related to sexual function and dysfunction.

COMMENTS

Four prospective and seven cross-sectional studies were found describing association between obesity and erectile dysfunction (ED). One cross-sectional study was found describing obesity and female sexual dysfunction (FSD). The prospective studies on ED all demonstrated a direct association and so did five of the seven cross-sectional studies. The single FSD study did not find any relationship. Eight intervention studies on weight loss and sexual difficulties were identified. All included few individuals and results were mixed even if most indicated an increase of sexual activity among both men and women after weight loss intervention.

CONCLUSION

Support for the assumption that obesity is associated with ED was found in both prospective and cross-sectional studies. FSD was not adequately described in the literature and prospective studies are needed here. Results from weight loss intervention studies are less conclusive, but also point toward improvement in sexual dysfunction with reduced weight.

Are age, anthropometry and components of metabolic syndrome-risk factors interrelated with lower urinary tract symptoms in patients with erectile dysfunction? A prospective study

AIM

To evaluate the effects of metabolic profiles on lower urinary tract symptoms (LUTS) in men with erectile dysfunction (ED).

METHODS

A total of 75 impotent men aged 25-75 years old (mean 58.1 years) were included in the study on a prospective basis. Patients were evaluated with a complete history, physical examination, anthropometry and metabolic profiles. LUTS were assessed using the International Prostate Symptom Score (IPSS).

RESULTS

Overall, there was no correlation between the IPSS and continuous parameters. However, when continuous variables were categorized, some parameters were significantly associated with LUTS. Patients with triglyceride level of 150 mg/dL or higher had more severe symptoms than those with triglyceride levels less than 150 mg/dL (19.4 +/- 2.4 vs. 14.3 +/- 1.1, P = 0.033). When 40 mg/dL was chosen as the high-density lipoprotein (HDL)-cholesterol cut-off level, the IPSS was significantly different between the two groups divided by 40 mg/dL (19.4 +/- 2.6 for HDL-cholesterol < 40 mg/dL vs. 14.4 +/- 1.0 for HDL-cholesterol = or > 40 mg/dL, P = 0.042). The area under the receiver operating characteristic curve (AUROCC) of triglyceride was 65.7% (95% confidence interval [CI], 52.6%-82.3%; P = 0.034) for severe LUTS. However, the AUROCC for 'HDL-cholesterol' was not significant (area, 65.4%; 95% CI, 48.2%-82.7%; P = 0.062). No other factors were determined to be significant in this regard.

CONCLUSION

The results of the present study indicate that some metabolic profiles might influence LUTS in men with ED.

Severity of erectile dysfunction in married impotent patients: interrelationship with anthropometry, hormones, metabolic profiles and lifestyle

OBJECTIVE

This study was designed to evaluate the effects of risk factors for erectile dysfunction (ED) or cardiovascular disease on the disease severity in impotent men.

METHODS

A total of 87 men, 25-75 years old (mean age, 53.4) were included in the study. Patients were evaluated with anthropometry, hormones, metabolic profiles and lifestyle. Baseline erectile function (EF) was evaluated using the International Index of Erectile Function (IIEF). The severity of ED was classified into the following four grades based on the six-item EF domain of the IIEF: severe (6-10); moderate (11-16); mild to moderate (17-21); and mild (22-25). Patients were deemed to have metabolic syndrome (MS) if they had three or more of five criteria according to National Cholesterol Education Program, with some modification.

RESULTS

Of 87 patients, 15 patients (17.2%) had mild, 11 (12.6%) had mild to moderate, 33 (37.9%) had moderate and 28 (32.3%) had severe ED. There was no correlation between scores of IIEF or EF domain and continuous parameters. On the multivariate model used, hypertensive patients had 26-fold higher risk (odds ratio, 26.195; 95% confidence interval, 1.463-46.072; P = 0.027) of severe ED than those without hypertension. Other factors were not significant.

CONCLUSION

The results of the study indicate that MS might not influence the severity of ED in impotent men. However, our findings suggest that hypertension plays a role in the disease severity in these patients.

[Metabolic syndrome and erectile dysfunction. Epidemiologic associations and pathogenetic links]

There is abundant evidence for the association between erectile dysfunction (ED) and the traditional atherosclerotic risk factors, such as dyslipidemia, hypertension, glucose intolerance, and obesity, that make up the metabolic syndrome. Recent findings have demonstrated a linear relationship between the number of these risk factors and the prevalence of ED. There is also growing evidence that endothelial dysfunction characterized by decreased bioavailability of nitrogen monoxide (NO) and a proinflammatory, prothrombotic, and proliferative phenotype is the common pathogenetic pathway linking ED to peripheral vascular diseases. Since ED often occurs several years before any clinical manifestation of systemic cardiovascular disease, ED should be seen as a warning of early atherosclerotic disease and an opportunity for doctor and patient to initiate preventive measures.

Erectile Dysfunction as a Predictor of the Metabolic Syndrome in Aging Men: Results From the Massachusetts Male Aging Study

PURPOSE

The metabolic syndrome, characterized by central obesity, insulin dysregulation, abnormal lipids and borderline hypertension, is a precursor state for cardiovascular disease. We determined whether erectile dysfunction is predictive of the metabolic syndrome.

MATERIALS AND METHODS

Data were obtained from the Massachusetts Male Aging Study, a population based prospective cohort observed at 3 points during approximately 15 years (T(1)-1987 to 1989, T(2)-1995 to 1997, T(3)-2002 to 2004). The metabolic syndrome was defined by using a modification of the Adult Treatment Panel III guidelines. The association between erectile dysfunction and the metabolic syndrome was assessed using relative risks and 95% confidence intervals estimated using Poisson regression models.

RESULTS

Analysis was conducted of 928 men without the metabolic syndrome at T(1). There were 293 men with incident metabolic syndrome, of which 56 had erectile dysfunction at baseline. Body mass index and the presence of 1 or 2 conditions constituting the metabolic syndrome definition were the strongest predictors of the metabolic syndrome. The association of erectile dysfunction with the metabolic syndrome (unadjusted RR 1.35, 95% CI 1.01-1.81) was modified by body mass index, with a stronger effect of erectile dysfunction in men with body mass index less than 25 (adjusted RR 2.09, 95% CI 1.09-4.02), and no erectile dysfunction and metabolic syndrome association in men with body mass index 25 or greater (adjusted RR 1.06, 95% CI 0.76-1.50).

CONCLUSIONS

Erectile dysfunction was predictive of the metabolic syndrome only in men with body mass index less than 25. This finding suggests that erectile dysfunction may provide a warning sign and an opportunity for early intervention in men otherwise considered at lower risk for the metabolic syndrome and subsequent cardiovascular disease.

A central role of eNOS in the protective effect of wine against metabolic syndrome

The positive health effects derived from moderate wine consumption are pleiotropic. They appear as improvements in cardiovascular risk factors such as plasma lipids, haemostatic mechanisms, endothelial function and antioxidant defences. The active principles would be ethanol and mainly polyphenols. Results from our and other laboratories support the unifying hypothesis that the improvements in risk factors after red wine consumption are mediated by endothelial nitric oxide synthase (eNOS). Many genes are involved, but the participation of eNOS would be a constant feature. The metabolic syndrome is a cluster of metabolic risk factors associated with high risk of cardiovascular disease (CVD). The National Cholesterol Education Programmmes Adult Treatment Panel III (NCEPATP III) clinical definition of the metabolic syndrome requires the presence of at least three risk factors, from among abdominal obesity, high plasma triacylglycerols, low plasma HDL, high blood pressure and high fasting plasma glucose. The molecular mechanisms responsible for the metabolic syndrome are not known. Since metabolic syndrome apparently affects 10-30% of the population in the world, research on its pathogenesis and control is needed. The recent finding that eNOS knockout mice present a cluster of cardiovascular risk factors comparable to those of the metabolic syndrome suggests that defects in eNOS function may cause human metabolic syndrome. These mice are hypertensive, insulin resistant and dyslipidemic. Further support for a pathogenic role of eNOS comes from the finding in humans that eNOS polymorphisms associate with insulin resistance and diabetes, with hypertension, with inflammatory and oxidative stress markers and with albuminuria. So, the data sustain the hypothesis that eNOS enhancement should reduce metabolic syndrome incidence and its consequences. Therefore red wine, since it enhances eNOS function, should be considered as a potential tool for the control of metabolic syndrome. This hypothesis is supported by epidemiological observations and needs experimental validation in human intervention studies.

Sildenafil: efficacy, safety, tolerability and mechanism of action in treating erectile dysfunction

Sildenafil citrate is marketed under the trademark name Viagra and is widely used to treat male erectile dysfunction; therapeutic uses of this medication for other diseases related to vascular dysfunction are emerging. When used as recommended, the drug has a strong clinical efficacy and safety profile in a broad spectrum of the male population. Its widespread use and effects of long-term exposure to the drug due to particular treatment regimens or inappropriate use mandate an ongoing update of its molecular mechanism, pharmacological profile and associated safety issues. This review focuses on biochemical and pharmacological features of sildenafil, the active component in Viagra, interaction of sildenafil with phosphodiesterase 5, pharmacokinetic parameters, action in smooth muscle, side effects, safety profile and prospects for other uses.