A systematic review of the association between erectile dysfunction and cardiovascular disease

Association of peripheral microvascular dysfunction and erectile dysfunction

PURPOSE

Increasing evidence of a link between erectile dysfunction and cardiovascular disease suggests a shared vascular etiology with endothelial dysfunction as a plausible underlying biological mechanism. To our knowledge whether this association is different for large arterial endothelium compared to microvascular endothelium has not yet been established. We investigated the association of erectile dysfunction with macrovascular and microvascular endothelial function.

MATERIALS AND METHODS

A sample of 390 men with a mean age of 55.5 years was recruited from the BACH survey, a population based survey of urological symptoms. Erectile dysfunction was assessed using IIEF-5. The percent of brachial artery flow mediated dilatation, a measure of macrovascular function, and hyperemic flow velocity in cm per second, a measure of microvascular function, were assessed by ultrasound. Linear regression was used to assess the association of erectile dysfunction and endothelial function, and adjust for potential confounders.

RESULTS

Reactive hyperemia was lower in men with vs without erectile dysfunction (mean ± SE 97.1 ± 2.5 vs 106.0 ± 1.6 cm per second, p = 0.003). However, the difference in flow mediated dilatation between men with vs without erectile dysfunction was statistically nonsignificant (mean 6.6% ± 0.33% vs 7.2% ± 0.24%, p = 0.147). The association of erectile dysfunction with reactive hyperemia was attenuated but it remained statistically significant in men with moderate to severe erectile dysfunction (IIEF-5 less than 12) after adjusting for traditional cardiovascular risk factors (p = 0.038).

CONCLUSIONS

These results provide evidence of greater microvascular than macrovascular endothelial dysfunction as a potential contributor to erectile dysfunction and an underlying mechanism linking erectile dysfunction and cardiovascular disease.

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

Erectile dysfunction confers an independent risk for cardiovascular events and total mortality. Aortic pulse wave velocity (PWV) is an important predictor of cardiovascular events and all-cause mortality. We investigated whether PWV predicts major adverse cardiovascular events (MACEs) in patients with erectile dysfunction beyond traditional risk factors. MACEs in relation to PWV were analyzed with proportional hazards models in 344 patients (mean age, 56 years) without established cardiovascular disease. During a mean follow-up of 4.7 years (range, 1–8.5 years), 24 of 344 participants (7.0%) experienced a MACE. Subjects in the highest PWV tertile (>8.8 m/s) had a 4-fold higher risk of MACEs compared with those in the lowest PWV tertile (<7.6 m/s; adjusted hazard ratio, 3.97; P =0.035). A PWV value of 7.81 m/s was associated with a negative predictive value (ability to rule out MACE) of 98.1%. Addition of PWV to standard risk factor model yielded correct patient reclassification to higher or lower risk category by 27.6% ( P =0.0332) in the whole cohort. Our results show that higher aortic stiffness is associated with increased risk for a MACE in patients with erectile dysfunction without known cardiovascular disease. Aortic PWV improves risk prediction when added to standard risk factors and may represent a valuable biomarker of prediction of cardiovascular disease risk in these patients.

Lipoprotein-associated phospholipase A2 levels are associated with erectile dysfunction in patients without known coronary artery disease

Endothelial dysfunction and microvascular damage play a crucial role in the pathogenesis of erectile dysfunction (ED). Lp-PLA2 is a calcium-independent member of the phospholipase A2 family and hydrolyses oxidised phospholipids on low-density lipoprotein (LDL) particles that plays a pivotal role in ox-LDL-induced endothelial dysfunction. The purpose of the current study was to determine the association between Lp-PLA2 levels and ED in patients without known coronary artery disease (CAD). All patients were evaluated for ED and divided into two groups: 88 patients suffering from ED for >1 year were enrolled as an experimental group and 88 patients without ED were enrolled as a control group in this study. Diagnosis of ED was based on the International Index of Erectile Function Score-5. Levels of Lp-PLA2 were measured in serum by colorimetric assay. The relationship between Lp-PLA2 levels and ED in patients was evaluated statistically. The mean age of patients with ED group was 59.4 ± 11.32 and 55.8 ± 9.67 in the control group. Plasma Lp-PLA2 levels were significantly higher in ED than in the control group (220.3 ± 66.90 and 174.8 ± 58.83 pg ml(-1) , respectively, P < 0.001). The Lp-PLA2 levels were negatively correlated with score of ED (r = -0.482, P < 0.05). In logistic regression analysis, enhanced plasma Lp-PLA2 levels result in approximately 1.2-fold increase in ED [1.22 (1.25-2.76)]. In this study, serum Lp-PLA2 levels were found to be associated with endothelial dysfunction predictive of ED. Serum Lp-PLA2 level appears to be a specific predictor of ED, and it may be used in early prediction of ED in the male population.

Effect of Endurance Cardiovascular Training Intensity on Erectile Dysfunction Severity in Men With Ischemic Heart Disease

The protective effect of physical activity on arteries is not limited to coronary vessels, but extends to the whole arterial system, including arteries, in which endothelial dysfunction and atherosclerotic changes are one of the key factors affecting erectile dysfunction development. The objective of this study was to report whether the endurance training intensity and training-induced chronotropic response are linked with a change in erectile dysfunction intensity in men with ischemic heart disease. A total of 150 men treated for ischemic heart disease, who suffered from erectile dysfunction, were analyzed. The study group consisted of 115 patients who were subjected to a cardiac rehabilitation program. The control group consisted of 35 patients who were not subjected to any cardiac rehabilitation. An IIEF-5 (International Index of Erectile Function) questionnaire was used for determining erectile dysfunction before and after cardiac rehabilitation. Cardiac training intensity was objectified by parameters describing work of endurance training. The mean initial intensity of erectile dysfunction in the study group was 12.46 ± 6.01 (95% confidence interval [CI] = 11.35-13.57). Final erectile dysfunction intensity (EDI) assessed after the cardiac rehabilitation program in the study group was 14.35 ± 6.88 (95% CI = 13.08-15.62), and it was statistically significantly greater from initial EDI. Mean final training work was statistically significantly greater than mean initial training work. From among the parameters describing training work, none were related significantly to reduction of EDI. In conclusion, cardiac rehabilitation program-induced improvement in erection severity is not correlated with endurance training intensity. Chronotropic response during exercise may be used for initial assessment of change in cardiac rehabilitation program-induced erection severity.

Treatment strategies for diabetic patients suffering from erectile dysfunction: an update

INTRODUCTION

Erectile dysfunction (ED) is one of the most common complications of diabetes. The complex pathophysiology of this disease makes it difficult to create clinical treatments tailored specifically for diabetic patients.

AREAS COVERED

This article will provide an update of both medical and surgical treatment approaches for diabetic ED, as well as discuss established treatments that are the cornerstone of this field.

EXPERT OPINION

Currently, PDE type 5 inhibitors represent the first-line treatment for all patients with ED. In the interim since this article's first publication several new PDE5 inhibitors have come to market. Several others that were previously on the market are now available for daily dosing. Analysis of both testosterone level and hemoglobin A1c is an essential part of treatment. Intracavernosal injections and vacuum constriction devices remain safe, and are highly effective treatment options. The implantable penile prosthesis remains a safe, and definitive treatment modality for those patients with refractory ED. Over the coming years as the understanding of the underlying causes of diabetic ED continues, the development of new, noninvasive, but effective medical treatments will lead to even more options for the treatment of this difficult disease.