Neelima V. Chu, MD, is an endocrinology fellow in the Division of Endocrinology and Metabolism at the University of California, San Diego. Steven V. Edelman, MD, is an associate professor of medicine in the Division of Endocrinology and Metabolism at the University of California, San Diego, and the Division of Endocrinology and Metabolism at the San Diego VA Health Care Systems in San Diego. He is founder and director of Taking Control of Your Diabetes, a nonprofit organization, and an associate editor of Clinical Diabetes.
Talk with your doctor about your sexual health. Do not be shy or embarrassed. Your doctor has probably dealt with this issue before. If your doctor is an older man, he might even have ED. First, your doctor will figure out what is causing your ED, which can usually be done just by talking with you. Next, your doctor will look for risk factors for atherosclerosis (the Table) by asking you questions, checking your blood pressure, and performing a few blood tests. Identifying and successfully treating atherosclerotic risk factors can reduce the chance of developing major vascular events (heart attacks and strokes).
Other treatment options such as penile self-injection therapy, external vacuum pumps and the medicated urethral system for erection are on rare occasions an effective long-term treatment. A very small percentage of men will continue with these treatments as evidenced by a very high drop out rate and a very low refill rate for these treatments. These procedures require extensive planning which interfere with sexual spontaneity and are really not a realistic long-term treatment for young patients with permanent ED.
Penile erection is largely a vascular process, and the penile endothelium and smooth muscle tissue are very sensitive to functional and structural changes. Vasculogenic ED results from an impairment of endothelial dependent or independent smooth muscle relaxation (functional vascular ED, initial stages), occlusion of the cavernosal arteries by atherosclerosis (structural vascular ED, late stages), or a combination of these.3 Current data support a complex interplay between endothelial dysfunction, subclinical inflammation, and androgen deficiency (Figure 1). The relationship between ED and CAD at the clinical level is supported by this common pathophysiological basis. The ‘artery size’ hypothesis explains why patients with CAD frequently report ED before CAD detection.10 According to this hypothesis, for a given atherosclerotic burden, the smaller penile arteries suffer obstruction earlier than the larger coronary arteries (Figure 2). The same concept holds also true in the case of non-obstructing atherosclerosis: since the smaller penile artery have a greater endothelial surface and erection requires a large degree of vasodilation to occur when compared with arteries in other organs, the same degree of endothelial dysfunction will be symptomatic in these smaller vessels but subclinical in the larger ones (i.e. coronaries). In the same context, accelerated arterial ageing (as indicated by increased arterial stiffening that also affects large arteries of ED patients) may be a common background.11,12 Erectile dysfunction is associated with an incremental inflammatory and endothelial-pro-thrombotic activation.13 Interestingly, this activation is equal to that found in CAD patients with no ED, while when these two conditions are combined the burden is additive. Androgen deficiency may be also implicated in the common pathogenetic pathways of ED and CVD; however, this warrants further substantiation.2
Nehra A, Jackson G, Miner M, Billups KL, Burnett AL, Buvat J, Carson CC, Cunningham GR, Ganz P, Goldstein I, Guay AT, Hackett G, Kloner RA, Kostis J, Montorsi P, Ramsey M, Rosen R, Sadovsky R, Seftel AD, Shabsigh R, Vlachopoulos C, Wu FC. The Princeton III Consensus recommendations for the management of erectile dysfunction and cardiovascular disease, Mayo Clin Proc , 2012, vol. 87 (pg. 766-778)https://doi.org/10.1016/j.mayocp.2012.06.015
Crossref | PubMed | Scopus (539) | Google ScholarSee all References Aside from the economic costs, ED can have severe psychological effects, resulting in poor self-image, decreased self-esteem, depression, and mental stress, and negative effects on personal relationships.2x2NIH Consensus Development Panel on Impotence. NIH Consensus Conference: impotence. JAMA. 1993; 270: 83–90
Crossref | PubMed | Scopus (23) | Google ScholarSee all References Vardenafil has been shown to be significantly more effective than placebo in the treatment of ED secondary to diabetes mellitus and after radical retropubic prostatectomy.69x69Goldstein, I, Young, JM, Fischer, J, Bangerter, K, Segerson, T, Taylor, T, and Vardenafil Diabetes Study Group. Vardenafil, a new phosphodiesterase type 5 inhibitor, in the treatment of erectile dysfunction in men with diabetes: a multicenter double-blind placebo-controlled fixed-dose study. Diabetes Care. 2003; 26: 777–783
Now that we better appreciate the complex sequence of events necessary for erections to occur, it’s no surprise that testosterone alone yields less than perfect results. Erectile dysfunction represents more than just low testosterone, which is just one facet of the spectrum of dysfunctional phenomena that cause sexual dysfunction. Nonetheless, when testosterone is combined with popular drugs like Viagra®, success is enhanced to an even greater degree—orgasmic function improves, along with erectile capacity and libido.20 Testosterone also activates penile nitric oxide; ultrasound studies have demonstrated a 27% increase in arterial blood flow into the penis with testosterone supplementation.23
Gene therapy has the potential to become a future management option for patients with CAD and ED. Animal studies have been conducted to evaluate the effects of gene therapy. A rat model was studied by Bivalacqua et al. to evaluate the effect of the combination of eNOS gene therapy and sildenafil. This research suggested that erectile response was greater in male rats with diabetes treated with combination eNOS gene therapy and sildenafil, compared with male rats with diabetes treated with eNOS gene therapy or sildenafil alone.76–78
Undoubtedly, heart disease is and will continue to be one of the major health problems of modern society. Approximately one death every forty seconds occurs due to cardiovascular (CV) disease in the United States alone and arterial hypertension is one of the greatest culprits for it. Considering the fact that around 25% of the global population suffer from arterial hypertension, predicted to reach 1.5 billion people in the foreseeable future, it is easily deducted that a respectful part of the general population is under major and constant CV risk[2,3].
Current American College of Cardiology/American Heart Association guidelines quote an absolute contraindication to sildenafil use in the setting of chronic nitrate treatment or the use of short-acting nitrate medications.10x10Kloner, RA and Zusman, RM. Cardiovascular effects of sildenafil citrate and recommendations for its use. Am J Cardiol. 1999; 84: 11N–17N
Abstract | Full Text | Full Text PDF | PubMed | Scopus (95) | Google ScholarSee all References Phosphodiesterase type 5 is found predominantly in the smooth muscle of the corpora cavernosa but can be found in smaller quantities in platelets and other vascular smooth muscle.56x56Wallis, RM, Corbin, JD, Francis, SH, and Ellis, P. Tissue distribution of phosphodiesterase families and the effects of sildenafil on tissue cyclic nucleotides, platelet function, and the contractile responses of trabeculae carneae and aortic rings in vitro. Am J Cardiol. 1999; 83: 3C–12C
Abstract | Full Text | Full Text PDF | PubMed | Scopus (272) | Google ScholarSee all References No data suggested adverse interactions between sildenafil and other drugs commonly used in the treatment of coronary artery disease, such as aspirin, heparin, or narcotics.10x10Kloner, RA and Zusman, RM. Cardiovascular effects of sildenafil citrate and recommendations for its use. Am J Cardiol. 1999; 84: 11N–17N
Abstract | Full Text | Full Text PDF | PubMed | Scopus (30) | Google ScholarSee all References Penile sympathetic stimulation flows through several pathways, including the sympathetic chain ganglia, which also supply such structures as the heart and vascular system. Sympathetic tone precipitates release of norepinephrine from penile adrenergic nerves, resulting in tonic contraction of cavernosal smooth muscle and its vasculature, thereby keeping the penis flaccid.9x9Andersson, K and Stief, C. Penile erection and cardiac risk: pathophysiologic and pharmacologic mechanisms. Am J Cardiol. 2000; 86: 23F–26F
Erectile dysfunction (ED) is a common disorder that affects the quality of life of many patients. It is prevalent in more than half of males aged over 60 years. Increasing evidence suggests that ED is predominantly a vascular disorder. Endothelial dysfunction seems to be the common pathological process causing ED. Many common risk factors for atherosclerosis such as diabetes, hypertension, smoking, obesity and hyperlipidaemia are prevalent in patients with ED and so management of these common cardiovascular risk factors can potentially prevent ED. Phosphodiesterase type 5 inhibitors provide short-term change of haemodynamic factors to help initiate and maintain penile erection. They have been shown to be an effective and safe treatment strategy for ED in patients with heart disease, including those with ischaemic heart disease and hypertension.
The pilot study by Vardi et al. (18) showed that LIESWT was effective in treating men with ED, suggesting a physiologic impact of LIESWT on cavernosal hemodynamics. The LIESWT is an effective penile rehabilitation tool that improves erectile function and potentially reverses underlying ED. Recent meta-analysis (19) of 14 studies showed that LiESWT could significantly improve the International Index of Erectile Function (IIEF) [mean difference: 2.00; 95% confidence interval (CI), 0.99–3.00; P<0.0001] and Erection Hardness Score (EHS) (risk difference: 0.16; 95% CI, 0.04–0.29; P=0.01). In addition, the therapeutic efficacy was noted to last for at least 3 months. LiESWT has been cited to a potential cure for ED, unlike other well established non-surgical methods of treatment (i.e., PDE5i, ICI and VED) being on demand treatments.
Finding a satisfying solution to ED can be a life-changing event for many men and their partners. In one study of 200 patients and 120 partners, both men and their partners found the AMS penile implant to be satisfying. 92% of patients and 96% of their partners reported sexual activity to be excellent or satisfactory.10 Talk to your doctor about your ED treatment options.
The pathophysiological basis for the predictive ability of ED has been discussed above. It should be emphasized, however, that ED should not only be viewed as a manifestation of obstructive CAD that could be identified by ischaemia revealing tests. Owing to the inflammatory and pro-thrombotic activation of the disease,13 it should also be regarded as an early warning sign of an imminent acute event (mainly acute myocardial infarction)22 due to the rupture of a subclinical plaque, and thus identification of the risk should ideally include plaque vulnerability tests. Finally, an issue that has important clinical implications is by how long the clinical manifestation of ED precedes the clinical manifestation of CAD. According to studies, men with ED and no cardiac symptoms have an increased incidence of experiencing a cardiac event, both acute and chronic, in the ensuing 2–5 years, thus providing a ‘window of opportunity’ for risk reduction management in these patients.2
This disparity is due not only to the setting in which the patients were accrued, but also to the manner in which they were questioned, because data in the Italian study were collected by the medical staff during subjects' visits for medical care, which might have also affected reporting rates. De Berardis et al.6 used a fairly generalizable cohort of 1,460 Italian men with type 2 diabetes accrued from 114 outpatient clinics and patient lists of 112 general practitioners. However, unlike the other Italian study, they used self-administered, validated questionnaires to assess the prevalence of ED among diabetic men. They found that 34% reported frequent erectile problems, and 24% reported moderate problems, for an overall prevalence of 58%. Depending on how one wishes to define “clinically significant” ED, this is probably a fairly accurate assessment.
Three FDA-approved oral medications, sildenafil, tadalafil, and vardenafil are available. These drugs are phosphodiesterase type 5 (PDE-5) inhibitors that can prolong levels of cGMP in tissue allowing improved smooth muscle relaxation, thus facilitating an erection. PDE-5 inhibitor drugs are effective in 56-63% of diabetic men with ED. More stringent glycemic control can improve these results. Men with testosterone deficiency may benefit from a combination of oral ED medication and testosterone supplementation.
PubMed | Google ScholarSee all References They evaluated 40 patients with coronary artery disease who underwent coronary artery catheterization and whose penile brachial index (PBI) was measured by Doppler ultrasonography. Although a positive correlation was noted between the PBI and the severity of coronary artery obstruction, the relationship was not strong. Also, the degree of PBI abnormality did not effectively stratify the patients according to the severity of their coronary artery blockage. This study concluded that the PBI used alone would not be an effective predictor of ischemic heart disease.
After getting a diagnosis of ED, most patients can begin treatment right away, but treatment may be delayed for some patients until the health of the heart is more fully assessed or improved. The most common treatment for ED is a pill (phosphodiesterase-5 inhibitor; PDE5-I): Viagra (sildenafil), Cialis (tadalafil), or Levitra (vardenafil). Each of these pills improves erections when taken before sexual activity; alternatively, a low dose of Cialis can be taken once a day. These medicines work by allowing the blood vessels that supply blood to the penis to dilate better during sexual stimulation. The PDE5-Is decrease blood pressure a little bit, but they are safe with most other medications and with other blood pressure pills. The PDE5-Is are not safe with nitrate medications like nitroglycerin, Nitrostat, Nitro Paste, Imdur, isosorbide mononitrate, and Isordil. Mixing a PDE5-I with a nitrate medication could result in severely low blood pressure and even death. Inform all medical professionals (including the ambulance or emergency department) about your most recent ED pill ingestion so that nitrates can be avoided. If you have high blood pressure or benign prostatic hypertrophy (enlarged prostate) and take medicines called α-blockers, your doctor may need to start you on the lowest dose of the PDE5-I.
Despite physician’s inexperience and patient’s reluctance to disclose sexual dysfunction problems, attempts to estimate the magnitude of this clinical condition have predicted that over 150 million men worldwide experience some degree of erectile dysfunction. Several studies have demonstrated a wide range regarding the prevalence of erectile dysfunction, which is even higher in patients with essential hypertension where the relative risk is approximately two times higher than in normotensive individuals[6-11]. The etiology can be found in the structural and functional abnormalities of the penile arteries induced by high blood pressure. Smooth muscle hypertrophy, stenotic lesions due to atherosclerosis and impaired blood flow are among the prominent structural alterations whereas endothelial dysfunction and the defective nitric oxide-induced vasodilatory mechanism belong to the main functional abnormalities induced by increased blood pressure[12,13]. As a matter of fact, sexual dysfunction is encountered more frequently that it is indeed believed underlining the need for a more proper and concrete assessment.
Medications used in the treatment of cardiovascular disease, especially antihypertensive medications, have been implicated frequently in the development of sexual dysfunction. A study of 5485 patients in the Hypertension Detection and Follow-up Program found that, during a 5-year period, 8.3% of male hypertensive patients stopped taking their antihypertensive medications secondary to sexual adverse effects.35x35Curb, JD, Borhani, NO, Blaszkowski, TP, Zimbaldi, N, Fotiu, S, and Williams, W. Long-term surveillance for adverse effects of antihypertensive drugs. JAMA. 1985; 253: 3263–3268
Following the breakthrough in ED treatment using PDE5-inhibitors, Western medicine has now moved on to a new frontier of regenerative medicine, with stem cell and gene therapy leading the way (25). There is a practical need for novel therapy as a significant portion of diabetic or post-prostatectomy ED patients do not respond to oral pharmacotherapy. To date, stem cells derived from different sites including adipose tissue-derived stem cells, bone marrow mesenchymal stem cells and muscle-derived stem cells have been investigated using animal models for ED, to study their effects on neural, vascular, endothelial or smooth muscle regeneration (25,26).
Your doctor may also choose to lower your dose of certain medications. Or your provider may switch the type of drug you’re taking if it’s interfering with your sex life. Some medicines used for managing blood pressure, insomnia, anxiety, depression, seizures and prostate problems increase the risk for erectile dysfunction. Beta-blockers (for high blood pressure), SSRIs (often used to treat depression) and the class of drugs called benzodiazepines (like Ativan, Xanax, Librium and Valium) are commonly tied to ED. You may want to speak to your doctor about this.
Abstract | Full Text | Full Text PDF | PubMed | Scopus (58) | Google ScholarSee all References Avoiding sexual activity between 6 AM and noon may be recommended to higher-risk patients because this is the time of peak incidence of most arrhythmias, myocardial ischemia, sudden cardiac death, and cerebrovascular accidents.1x1Muller, JE. Sexual activity as a trigger for cardiovascular events: what is the risk?. Am J Cardiol. 1999; 84: 2N–5N
If you take a diuretic, you should stay on it until high blood pressure is under control. If erection problems persist, or blood pressure goes back up, then your doctor might switch to a drug that's less likely to cause erectile dysfunction. Or, a combination of medications might work better to control high blood pressure and lower the risk of erectile dysfunction.
Side effects of sildenafil are similar to those from taking niacin or any vasodilator, namely, headaches, lightheadedness, dizziness, and flushing. Some individuals experience a bluish tinge of their cornea, which makes them feel as if they are wearing light blue–tinted sunglasses. This effect can last for several hours. Syncope and myocardial infarction, the most serious side effects, are seen in men who are also taking nitrates for coronary heart disease. Sildenafil also has adverse effects in people with hypertrophic cardiomyopathy because a decrease in preload and after load in the cardiac output can increase the outflow obstruction, culminating in an unstable hemodynamic state.
Abstract | Full Text | Full Text PDF | PubMed | Scopus (259) | Google ScholarSee all References Sildenafil should be used with caution in patients with liver dysfunction or renal impairment, as well as in patients taking any medications that inhibit the P-450 pathway such as cimetidine or erythromycin.3x3Zusman, RM, Morales, A, Glasser, DB, and Osterloh, IH. Overall cardiovascular profile of sildenafil citrate. Am J Cardiol. 1999; 83: 35C–44C
Relation between erectile dysfunction prevalence and type of coronary syndrome (A). Time interval (months) between erectile dysfunction and coronary artery disease symptom onset in chronic coronary syndrome according to the number of vessels involved (B). ACS, acute coronary syndrome; CCS, chronic coronary syndrome, G1: ACS and 1-VD; G2: ACS and 2-,3-VD; G3: CCS. VD, vessel disease; C: the control group with normal coronary angiography. With permission from Montorsi et al.15
Abstract | Full Text | Full Text PDF | PubMed | Scopus (30) | Google ScholarSee all References Erections result from relaxation of the corpora cavernosa, which is mediated either by increasing intracellular cyclic guanosine monophosphate (cGMP) or cyclic adenosine monophosphate or by inhibition of their degradation. Increased parasympathetic tone results in a decrease in norepinephrine release and an increase in the release of acetylcholine; subsequently, NO synthase activity increases, which releases NO from both endothelial cells and nonadrenergic, noncholinergic neurons.10x10Kloner, RA and Zusman, RM. Cardiovascular effects of sildenafil citrate and recommendations for its use. Am J Cardiol. 1999; 84: 11N–17N
27. Haahr MK, Jensen CH, Toyserkani NM, et al. Safety and Potential Effect of a Single Intracavernous Injection of Autologous Adipose-Derived Regenerative Cells in Patients with Erectile Dysfunction Following Radical Prostatectomy: An Open-Label Phase I Clinical Trial. EBioMedicine 2016;5:204-10. 10.1016/j.ebiom.2016.01.024 [PMC free article] [PubMed] [CrossRef]
DHEA is a hormone made by the human body. It’s a building block for testosterone. According to a study published in Urology, this supplement may be able to help men whose ED is related to having low testosterone. However, there’s no definitive evidence of this benefit. It’s clear that DHEA can cause various side effects, including liver damage and acne. Long-term use of DHEA can also cause hormonal imbalances.
According to the Cleveland Clinic, “because erectile dysfunction is caused by a complex set of psychosocial, neurologic, and vascular factors, a specific cause in a patient may remain ambiguous.” The root causes are often related to a blockage or dysfunction of blood vessels. For example, ED can be due to conditions like atherosclerosis or diabetes, hormonal imbalances or problems related to mental health. It’s been found that common causes typically include one or more of the following factors: (2)
A penile prosthesis is another treatment option for men with erectile dysfunction. These devices are either malleable (bendable) or inflatable. The simplest type of prosthesis consists of a pair of malleable rods surgically implanted within the erection chambers of the penis. With this type of implant the penis is always semi-rigid and merely needs to be lifted or adjusted into the erect position to initiate sex. Today, many men choose a hydraulic, inflatable prosthesis, which allows a man to have an erection whenever he chooses and is much easier to conceal. It is also more natural.
The authors observe that multiple factors may be involved. In addition to decreased exercise capacity, patients with chronic heart failure have blood vessel and circulation abnormalities that can reduce blood flow into the penis and interfere with the ability to maintain an erection. And erectile dysfunction can be caused or worsened by many of the medications that are commonly prescribed to treat chronic heart failure.
Before a man concludes that oral drugs don’t work for him, he should have his testosterone levels checked to rule out hormone deficiency as the cause of (or as a contributor to) his sexual dysfunction. Other symptoms of low testosterone include a low sex drive and infertility. Checking testosterone levels requires a blood test. If a man’s levels of testosterone are decreased or at the lower end of normal, his doctor may prescribe supplemental testosterone therapy, either as testosterone injections or testosterone gel, which is applied daily to the skin. In some cases, testosterone therapy alone can resolve sexual dysfunction, or it can be combined with the use of oral erectile dysfunction drugs.