Prediction of Cardiovascular Events With Aortic Stiffness in Patients With Erectile Dysfunction

Endothelial cell serum and glucocorticoid regulated kinase 1 (SGK1) mediates vascular stiffening

BACKGROUND

Excessive dietary salt intake increases vascular stiffness in humans, especially in salt-sensitive populations. While we recently suggested that the endothelial sodium channel (EnNaC) contributes to salt-sensitivity related endothelial cell (EC) and arterial stiffening, mechanistic understanding remains incomplete. This study therefore aimed to explore the role of EC-serum and glucocorticoid regulated kinase 1 (SGK1), as a reported regulator of sodium channels, in EC and arterial stiffening.

METHODS AND RESULTS

A mouse model of salt sensitivity-associated vascular stiffening was produced by subcutaneous implantation of slow-release deoxycorticosterone acetate (DOCA) pellets, with salt (1 % NaCl, 0.2 % KCl) administered via drinking water. Preliminary data showed that global SGK1 deletion caused significantly decreased blood pressure (BP), EnNaC activity and aortic endothelium stiffness as compared to control mice following DOCA-salt treatment. To probe EC signaling pathways, selective deletion of EC-SGK1 was performed by cross-breeding cadherin 5-Cre mice with sgk1flox/flox mice. DOCA-salt treated control mice had significantly increased BP, EC and aortic stiffness in vivo and ex vivo, which were attenuated by EC-SGK1 deficiency. To demonstrate relevance to humans, human aortic ECs were cultured in the absence or presence of aldosterone and high salt with or without the SGK1 inhibitor, EMD638683 (10uM or 25uM). Treatment with aldosterone and high salt increased intrinsic stiffness of ECs, which was prevented by SGK1 inhibition. Further, the SGK1 inhibitor prevented aldosterone and high salt induced actin polymerization, a key mechanism in cellular stiffening.

CONCLUSION

EC-SGK1 contributes to salt-sensitivity related EC and aortic stiffening by mechanisms appearing to involve regulation of actin polymerization.

The flow index provides a comprehensive assessment of erectile dysfunction by combining blood flow velocity and vascular diameter

Dynamic duplex sonography (DUS) is not comprehensive in the evaluation of arteriogenic erectile dysfunction (ED). We introduced a new parameter, the flow index (FI), into the assessment of arteriogenic ED. A retrospective review of a prospective database was conducted. Patients undergoing DUS and pelvic computed tomography angiography for the evaluation of ED were included. The FI was calculated from peak systolic velocity (PSV) and the percentages of pelvic arterial (PLA) stenosis. Correlations between PSV, PLA stenosis, the FI, and erectile function were calculated. Eighty-three patients were included. Compared with PSV, the FI had better correlations with the erection hardness score (EHS) (r_s = 0.405, P < 0.001 for FI; r_s = 0.294, P = 0.007 for PSV). For EHS < 3, the areas under the ROC curve of FI and PSV were 0.759 and 0.700, respectively. In patients with normal DUS but EHS < 3, PLA stenosis was more severe (62.5% vs. 10.0%, P = 0.015), and the FI was lower (8.35 vs. 57.78, P = 0.006), while PSV was not different. The FI is better than PSV in the evaluation of arteriogenic ED. On the other hand, assessment of the pelvic arterial system should be included in the evaluation of ED.

Interactions between erectile dysfunction, cardiovascular disease and cardiovascular drugs

Sexual health has a fundamental role in overall health and well-being, and a healthy and dynamic sex life can make an important contribution to a good quality of life. Sexual dysfunction, and especially erectile dysfunction (ED) in men, is highly prevalent in patients with cardiovascular disease (CVD). CVD and ED have shared risk factors and pathophysiological links, such as endothelial dysfunction, inflammation and low plasma testosterone levels. ED has been shown to be an independent and early harbinger of future CVD events, providing an important window to initiate preventive measures. Therefore, screening and diagnosing ED is essential for the primary and secondary prevention of CVD because the assessment of ED offers an easy and low-cost prognostic tool that is an alternative to other investigational cardiovascular biomarkers. Moreover, ED is a major contributing factor to the discontinuation of, or poor adherence to, cardiovascular therapy. Cardiovascular drugs have divergent effects on erectile function, with diuretics and β-blockers having the worst profiles, and renin-angiotensin-aldosterone system inhibitors and nebivolol having the best profiles. Pharmacological treatment of ED has an equivocal effect on the risk of CVD, suggesting a complex interaction between ED and drugs for CVD. In this Review, we discuss how sexual function could be incorporated into the patient history taken by physicians treating individuals with CVD, not merely as part of the diagnostic work-up but as a means to pursue tangible and essential benefits in quality of life and cardiovascular outcomes.

Can pulse wave velocity (PWV) alone express arterial stiffness? A neglected tool for vascular function assessment

Arterial stiffness, defined as the rigidity of the arterial wall, is the consequence of vascular aging and is associated with the full spectrum of cardiovascular diseases. Carotid-femoral pulse wave velocity (cf-PWV) is the gold standard method for arterial stiffness evaluation: it measures the velocity of the arterial pulse along the thoracic and abdominal aorta alongside arterial distensibility. Its value rises as stiffness progresses. Cf-PWV is helpful to assess residual cardiovascular risk (CVR) in hypertension (HT). In fact, an increase in pulsatility and arterial stiffness predicts CVR in patients affected by arterial HT, independently of other risk factors. Arterial stiffness can predict cardiovascular events in several other clinical conditions such as heart failure, diabetes, and pulmonary HT. However, cf-PWV has not been yet included in routine clinical practice so far. A possible reason might be its methodological and theoretical limitations (inaccuracy in the traveled distance, intra and interindividual variability, lack of well-defined references values, and age- and blood pressure-independent cutoff). To exceed these limits a strict adherence to guidelines, use of analytical approaches, and possibility of integrating the results with other stiffness examinations are essential approaches.

Mutation of the 5'-untranslated region stem-loop mRNA structure reduces type I collagen deposition and arterial stiffness in male obese mice

Arterial stiffening, a characteristic feature of obesity and type 2 diabetes, contributes to the development and progression of cardiovascular diseases (CVD). Currently, no effective prophylaxis or therapeutics is available to prevent or treat arterial stiffening. A better understanding of the molecular mechanisms underlying arterial stiffening is vital to identify newer targets and strategies to reduce CVD burden. A major contributor to arterial stiffening is increased collagen deposition. In the 5'-untranslated regions of mRNAs encoding for type I collagen, an evolutionally conserved stem-loop (SL) structure plays an essential role in its stability and post-transcriptional regulation. Here, we show that feeding a high-fat/high-sucrose (HFHS) diet for 28 wk increases adiposity, insulin resistance, and blood pressure in male wild-type littermates. Moreover, arterial stiffness, assessed in vivo via aortic pulse wave velocity, and ex vivo using atomic force microscopy in aortic explants or pressure myography in isolated femoral and mesenteric arteries, was also increased in those mice. Notably, all these indices of arterial stiffness, along with collagen type I levels in the vasculature, were reduced in HFHS-fed mice harboring a mutation in the 5'SL structure, relative to wild-type littermates. This protective vascular phenotype in 5'SL-mutant mice did not associate with a reduction in insulin resistance or blood pressure. These findings implicate the 5'SL structure as a putative therapeutic target to prevent or reverse arterial stiffening and CVD associated with obesity and type 2 diabetes.NEW & NOTEWORTHY In the 5'-untranslated (UTR) regions of mRNAs encoding for type I collagen, an evolutionally conserved SL structure plays an essential role in its stability and posttranscriptional regulation. We demonstrate that a mutation of the SL mRNA structure in the 5'-UTR decreases collagen type I deposition and arterial stiffness in obese mice. Targeting this evolutionarily conserved SL structure may hold promise in the management of arterial stiffening and CVD associated with obesity and type 2 diabetes.

Is the History of Erectile Dysfunction a Reliable Risk Factor for New Onset Acute Myocardial Infarction? A Systematic Review and Meta-Analysis

Acute myocardial infarction (AMI) occurs as a manifestation of coronary atherosclerotic disease. The occurrence of erectile dysfunction (ED) following AMI is well documented and this association and pathophysiology is often interrelated. Few studies have objectively assessed the diagnostic value of ED as a risk factor for AMI, in general. In this review, we aimed to better outline the diagnostic predictability of ED as a precursor for 'first/new onset' AMI. This review was performed using selective search terms, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The Cochrane, Embase, PubMed, Scopus and Web of Science databases were searched (September 2018). Selected studies were further assessed for relevance and quality (Critical Appraisal Skills Program tool-Oxford). Four studies [573 participants; mean 143 (SD ± 76.3604) and median 141 participants] were eligible for analysis. Meta-analysis of the studies resulted in a pooled sensitivity of 51.36% (95% CI: 47.37-55.33%). For the single study which reported true negative and false positive cases, a specificity of 76.53% (95% CI: 68.57-83.00%) was calculated. The results of this systematic review and meta-analysis suggest that a history of ED should be used as a risk factor for new onset AMI.

The Role of Vascular Smooth Muscle Cells in Arterial Remodeling: Focus on Calcification-Related Processes

Arterial remodeling refers to the structural and functional changes of the vessel wall that occur in response to disease, injury, or aging. Vascular smooth muscle cells (VSMC) play a pivotal role in regulating the remodeling processes of the vessel wall. Phenotypic switching of VSMC involves oxidative stress-induced extracellular vesicle release, driving calcification processes. The VSMC phenotype is relevant to plaque initiation, development and stability, whereas, in the media, the VSMC phenotype is important in maintaining tissue elasticity, wall stress homeostasis and vessel stiffness. Clinically, assessment of arterial remodeling is a challenge; particularly distinguishing intimal and medial involvement, and their contributions to vessel wall remodeling. The limitations pertain to imaging resolution and sensitivity, so methodological development is focused on improving those. Moreover, the integration of data across the microscopic (i.e., cell-tissue) and macroscopic (i.e., vessel-system) scale for correct interpretation is innately challenging, because of the multiple biophysical and biochemical factors involved. In the present review, we describe the arterial remodeling processes that govern arterial stiffening, atherosclerosis and calcification, with a particular focus on VSMC phenotypic switching. Additionally, we review clinically applicable methodologies to assess arterial remodeling and the latest developments in these, seeking to unravel the ubiquitous corroborator of vascular pathology that calcification appears to be.

Deterioration of sexual function is associated with central hemodynamics in adult Japanese men

Elevated aortic blood pressure is more strongly related to the onset of cardiovascular disease (CVD) than elevated brachial blood pressure. On the other hand, erectile dysfunction (ED) is a peripheral vascular disfunction and is also associated with CVD; however, the association between aortic blood pressure and ED has not yet been clarified. Therefore, we aimed to investigate the association between ED severity and aortic blood pressure in adult men. In 253 Japanese adult men (59 ± 16 years), aortic (estimated using a generalized transfer function) and peripheral hemodynamics were measured. Erectile function was assessed with a questionnaire (the International Index of Erectile Function 5: IIEF5), and participants were stratified into three groups based on the IIEF5 score (no ED, mild-to-moderate ED, and moderate-to-severe ED). Aortic systolic blood pressure (SBP) and pulse pressure (PP) were significantly higher in subjects with moderate-to-severe ED than in subjects with no ED or mild-to-moderate ED. In addition, the severity of ED was significantly associated with the time to reflection, augmentation pressure, and augmentation index. Multivariate linear regression analyses suggested that moderate-to-severe ED was significantly associated with aortic SBP and PP (β = 0.129; p = 0.047, β = 0.165; p = 0.013, respectively) but not brachial SBP or PP, after confounding factors were considered. These results suggest that moderate-to-severe ED is associated with elevated aortic blood pressure due to an earlier arrival of the reflected wave and is an independent predictor of elevated aortic blood pressure in Japanese men.

Vascular Response to Sildenafil Citrate in Aging and Age-Related Macular Degeneration

Age-related macular degeneration (AMD) - the leading cause of vision loss in the elderly - share many risks factors as atherosclerosis, which exhibits loss of vascular compliance resulting from aging and oxidative stress. Here, we attempt to explore choroidal and retinal vascular compliance in patients with AMD by evaluating dynamic vascular changes using live ocular imaging following treatment with oral sildenafil citrate, a phosphodiesterase type 5 (PDE5) inhibitor and potent vasodilator. Enhanced-depth imaging optical coherence tomography (EDI-OCT) and OCT angiography (OCT-A) were performed on 46 eyes of 23 subjects, including 15 patients with non-exudative AMD in one eye and exudative AMD in the fellow eye, and 8 age-matched control subjects. Choroidal thickness, choroidal vascularity, and retinal vessel density were measured across the central macula at 1 and 3 hours after a 100 mg oral dose of sildenafil citrate. Baseline choroidal thickness was 172.1 ± 60.0 μm in non-exudative AMD eyes, 196.4 ± 89.8 μm in exudative AMD eyes, and 207.4 ± 77.7 μm in control eyes, with no difference between the 3 groups (P = 0.116). After sildenafil, choroidal thickness increased by 6.0% to 9.0% at 1 and 3 hours in all groups (P = 0.001-0.014). Eyes from older subjects were associated with choroidal thinning at baseline (P = 0.005) and showed less choroidal expansion at 1 hour and 3 hours after sildenafil (P = 0.001) regardless of AMD status (P = 0.666). The choroidal thickening appeared to be primarily attributed to expansion of the stroma rather than luminal component. Retinal vascular density remained unchanged after sildenafil in all 3 groups (P = 0.281-0.587). Together, our studies suggest that vascular response of the choroid to sildenafil decreases with age, but is not affected by the presence of non-exudative or exudative AMD, providing insight into changes in vessel compliance in aging and AMD.

Sexual Function Is an Indicator of Central Arterial Stiffness and Arterial Stiffness Gradient in Japanese Adult Men

Background

As arterial stiffness increases in the absence of subjective symptoms, a personal indicator that reflects increased risk of cardiovascular disease is necessary. Penile erection is regulated by vascular function, and atherosclerosis affects the penile artery earlier than it affects the coronary and carotid arteries. Therefore, we hypothesized that deterioration of erectile function could be a marker of increased risk for cardiovascular disease. To test our hypothesis, we assessed erectile function and arterial stiffness in a cross‐sectional study.

Methods and Results

Carotid‐femoral pulse wave velocity (PWV), brachial‐ankle PWV, femoral‐ankle PWV, and arterial stiffness gradient (PWV ratio: carotid‐femoral PWV/femoral‐ankle PWV) were measured as indexes of central, systemic, and peripheral arterial stiffness and peripheral organ damage, respectively, in 317 adult men. In addition, erectile function was assessed by using the questionnaire International Index of Erectile Function 5 (a descending score indicates worsening of erectile function). The scores of male sexual function were inversely correlated with carotid‐femoral PWV (r_s=−0.41), brachial‐ankle PWV (r_s=−0.35), femoral‐ankle PWV (r_s=−0.19), and PWV ratio (r_s=−0.33). Furthermore, multivariate linear regression analyses revealed that International Index of Erectile Function 5 scores were significantly associated with carotid‐femoral PWV (β=−0.22) and PWV ratio (β=−0.25), but not with brachial‐ankle PWV and femoral‐ankle PWV.

Conclusions

Our results indicated that erectile function is independently associated with central arterial stiffness and peripheral organ damage. These findings suggest that male sexual function could be an easily identifiable and independent marker of increased central arterial stiffness and peripheral organ damage.

Central Haemodynamics and Prediction of Cardiovascular Events in Patients With Erectile Dysfunction

BACKGROUND

We investigated whether central hemodynamics predict major adverse cardiovascular events (MACEs) in erectile dysfunction (ED) patients beyond traditional risk factors.

METHODS

MACEs in relation to aortic pressures and augmentation index (AIx) were analyzed in 398 patients (mean age, 56 years) with ED but without established cardiovascular (CV) disease.

RESULTS

During the mean follow-up period of 6.5 years, a total of 29 (6.5%) MACEs occurred. The adjusted relative risk of MACEs was 1.062 (95% confidence interval (CI), 1.016-1.116) for a 10-mm Hg increase of aortic systolic pressure, 1.119 (95% CI, 1.036-1.155) for a 10-mm Hg increase of aortic pulse pressure (PP), and 1.191 (95% CI, 1.056-1.372) for a 10% absolute increase of AIx. While aortic pressures and AIx did not significantly improve the C-statistic models, the calibration for all indices was satisfactory. Regarding reclassification, the integrated discrimination improvement index (IDI) indicated improvement in risk discrimination of the models that included AIx and aortic PP compared to the reference model in identifying MACEs (IDI = 0.0069; P = 0.024, and IDI = 0.0060; P = 0.036, respectively). The based on categories for 10-year coronary heart disease risk and adapted at 6.5 years overall net reclassification index showed marginal and indicative risk reclassification for AIx (15.7%, P = 0.12) and aortic PP (7.2%, P = 0.20) respectively.

CONCLUSIONS

Our results show for the first time that higher central pressures and AIx are associated with increased risk for a MACE in ED patients without known CV disease. Considering the adverse prognostic role of central hemodynamics on outcomes, the present findings may explain part of the increased CV risk associated with ED.

Evaluation of arterial stiffness and cardiac function in patients with vascular erectile dysfunction: acute effects of phosphodiesterase-5 inhibitor tadalafil

This study aimed to detect endothelial dysfunction in erectile dysfunction (ED) patients free from cardiovascular diseases or atherosclerotic risk factors and to evaluate acute effects of phosphodiesterase-5 inhibitor tadalafil on endothelial dysfunction and cardiac function. Thirty ED patients and 20 healthy male subjects (mean ages: 48.7±11.7 and 48.3±8.7 years, respectively) were enrolled. Endothelium functions were assessed by applanation tonometry. Aortic stiffness and cardiac function were evaluated by transthoracic echocardiography. Pulse pressure was greater in the ED group (P<0.05), whereas aortic strain and aortic distensibility were significantly lower (P<0.001). Treatment with tadalafil reduced pulse pressure (P=0.0179), systolic blood pressure (P=0.001) and diastolic blood pressure (P=0.054) and increased aortic distensibility (P=0.001) and aortic strain (P=0.003) in the ED group. Tadalafil administration also increased large artery and small artery elasticity indices that were reduced in the ED group at baseline (P=0.02 and 0.003, respectively). Systemic vascular disease and compromised left ventricular diastolic function (LVDF) were present in ED patients with no known atherosclerotic risk factors and cardiac diseases. Tadalafil positively affected arterial stiffness and LVDF.

Biomarkers, erectile dysfunction, and cardiovascular risk prediction: the latest of an evolving concept

A number of circulating and imaging biomarkers are robustly associated with cardiovascular (CV) risk. The overall expectation from a biomarker in the erectile dysfunction (ED) setting is to enhance the optimal management of a man with this disorder but no clinical atherosclerosis. Evidence demonstrating that these biomarkers enhance risk prediction for individuals with ED is at this stage still limited for most of them. A better identification of the subsets of the ED population that require further risk stratification, as well as the initiation of randomized trials that will formally test the ability of biomarkers to predict CV risk, could make biomarker-guided prevention an attainable goal.

Can Erectile Dysfunction in Young Patients Serve as a Surrogate Marker for Coronary Artery Disease?

INTRODUCTION

Early diagnosis and expeditious management of coronary artery disease (CAD) has a rewarding survival benefit.

AIM

To study whether erectile dysfunction (ED) serves as a surrogate marker for CAD in a young patient.

SETTINGS AND DESIGN

Males (n=207) between ages 20-60 years with ED were evaluated prospectively for risk factors for CAD.

MATERIALS AND METHODS

Blood Glucose Levels (BGL) fasting and post meal), lipid profile (LP) and 12 lead electrocardiogram (ECG) was done in all of them. International Index of Erectile Function-5 (IEF-5) was used for the evaluation of ED. Those with abnormal parameters were assessed by cardiologists by echocardiography, stress test and if necessary coronary angiography (Non-Invasive or Invasive).

STATISTICAL ANALYSIS

All the data were analysed using SPSS. 16 statistical software (SPSS Inc., Chicago, IL, USA). All data are expressed as mean and standard deviation. The Student's t-test was used to compare means between groups, and the chi-square test was used to compare proportions between the groups. P-value <0.05 was considered statistically significant. All confidence intervals (CIs) are two tailed and calculated at the 0.05 level.

RESULTS

Out of 207, 149 patients had at least one abnormal screening parameter. All underwent cardiology consultation and 2D ECHO and Stress test. Thirty six patients underwent coronary angiography. CAD was found in 22 patients. Of these, 19 patients had severe ED. Nine patients were between 20-40 years of age (13.23%). All 9 young patients had deranged LP; severe ED. Six patients were smokers while nobody was hypertensive.

CONCLUSION

ED serves as a surrogate marker for CAD in young patients (p=0.001). Presence of risk factors and lab abnormalities in young patients with ED warrants a cardiology referral to detect CAD.

Prevalence of erectile dysfunction in a cohort of Italian hypertensive subjects

The aim of this study was to evaluate the prevalence of erectile dysfunction (ED) in a cohort of Italian hypertensive men and the association with clinical and biochemical data. The study involved 270 consecutive hypertensive subjects aged 40-70 years evaluated in Italian Hypertension Centers of six hospitals from Liguria and Piedmont. ED was assessed through the self-administered questionnaire of the International Index of Erectile Function. Clinical history with ongoing drug treatment, various clinical parameters, biochemical data and evidence about the presence of subclinical target organ damage was collected. Twenty-seven subjects refused to answer the questionnaire (10%). Among the 243 remained subjects, 123 presented ED (50.6%). ED was highly related to age, systolic blood pressure, pulse pressure, smoking status, statin therapy and kidney function. The addition of a thiazide diuretic to an inhibitor of the renin-angiotensin system significantly increased the prevalence of ED. The prevalence of ED increased in relation with the number of hypotensive drug classes taken by the patients. ED was highly prevalent in this cohort of Italian hypertensive subjects and was associated with other cardiovascular risk factors, such as age, smoking status and kidney function. The role of ED as an early marker of cardiovascular disease is discussed.

Risk of erectile dysfunction in transfusion-naive thalassemia men: a nationwide population-based retrospective cohort study

Based on the mechanism of pathophysiology, thalassemia major or transfusion-dependent thalassemia patients may have an increased risk of developing organic erectile dysfunction resulting from hypogonadism. However, there have been few studies investigating the association between erectile dysfunction and transfusion-naive thalassemia populations. We constructed a population-based cohort study to elucidate the association between transfusion-naive thalassemia populations and organic erectile dysfunction. This nationwide population-based cohort study involved analyzing data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified men with transfusion-naive thalassemia and selected a comparison cohort that was frequency-matched with these according to age, and year of diagnosis thalassemia at a ratio of 1 thalassemia man to 4 control men. We analyzed the risks for transfusion-naive thalassemia men and organic erectile dysfunction by using Cox proportional hazards regression models. In this study, 588 transfusion-naive thalassemia men and 2337 controls were included. Total 12 patients were identified within the thalassaemia group and 10 within the control group. The overall risks for developing organic erectile dysfunction were 4.56-fold in patients with transfusion-naive thalassemia men compared with the comparison cohort after we adjusted for age and comorbidities. Our long-term cohort study results showed that in transfusion-naive thalassemia men, there was a higher risk for the development of organic erectile dysfunction, particularly in those patients with comorbidities.