Testosterone therapy (TTh) should be reserved for patients who (i) are symptomatic (ED or reduced libido) of testosterone deficiency45 and (ii) they have biochemical evidence of low testosterone (TT <8 nmol/L or 2.3 ng/mL). In men with borderline TT (8–12 nmol/L or 2.3–3.5 ng/mL), a TTh trial (for 3–6 months and continuation if effective) may be envisaged. While adding a PDE5 inhibitor can be considered in men who have not improved with TTh, the usual clinical scenario is to add TTh in patients who have not responded to PDE5 inhibitors. Improvement is dependent on the testosterone levels with better results being obtained at lower levels of TT.45 Despite evidence of benefit in patients with pre-existing cardiovascular conditions (angina or heart failure), it should be emphasized that TTh is not a medication with cardiovascular indications.
For those patients who cannot take erectile dysfunction medications, the authors counsel that an exercise training regimen may be an appropriate substitute therapy to enhance sexual function and quality of life. The authors stress that clinicians should focus on the sexual activity history of chronic heart failure patients and not ignore it, since addressing this element can substantially improve their quality of life.
The bad news: Men with diabetes are three times more likely to report having problems with sex than non-diabetic men. The most common sexual problem is Erectile Dysfunction, or ED, sometimes called impotence. Even worse, because ED is such a private issue, many men feel embarrassed to discuss the problem with their doctor, or even their partner, so the problem is never addressed.
Few simple laboratory tests can help identify obvious causes of organic ED. Initial labs should include HbA1c, free testosterone, thyroid function tests, and prolactin levels. However, patients who do not respond to pharmacological therapy or who may be candidates for surgical treatment may require more in-depth testing, including nocturnal penile tumescence testing, duplex Doppler imaging, somatosensory evoked potentials, or pudendal artery angiography.
Relaxation of erectile tissue requires nitric oxide from nonadrenergic-noncholinergic neurons and the endothelium.21 Penile tissue from diabetic men with ED demonstrates impaired neurogenic and endothelium-mediated relaxation of smooth muscle,22 increased accumulation of advanced glycation end products (AGEs),23 and upregulation arginase, a competitor with nitric oxide synthase for its substrate L-arginine.24 Normal responses to direct smooth muscle relaxants in most of these studies implies that the impairments are due to decreased synthesis, release, or activity of nitric oxide. The fundamental mechanisms mediating these changes are thought to be the same as for other diabetic complications: increased polyol pathway flux, intracellular accumulation of AGEs, activation of protein kinase C, and increased flux through the hexosamine pathway.25
Abstract | Full Text | Full Text PDF | PubMed | Scopus (395) | Google ScholarSee all References The maximum decrease in blood pressure level was noted at 1 hour after the oral dose was taken and was correlated with peak plasma levels. The blood pressure level in these patients returned to baseline within 4 hours.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
Olsson et al. conducted a randomised, double-blind, placebo-controlled, parallel group, and flexible dose study in 224 men with ED and one CVD, including IHD (20 %) and hypertension (80 %). This study reported that the sildenafil-treated group showed 71 % improvement in ED compared with the placebo-controlled group (24 %).64 Furthermore, no treatment-related cardiovascular adverse events were reported.65 Conti et al. showed in an early study that sildenafil is an effective treatment for ED in patients with IHD; the majority of patients reported improvement in penile erection with it.66 Another double-blind, placebo-controlled study of patients with ED and stable CAD showed statistically significant improvement with sildenafil versus placebo in both the frequency of penetration and frequency of maintained erections after penetration.67
Abstract | Full Text | Full Text PDF | PubMed | Scopus (66) | Google ScholarSee all References However, some researchers have questioned whether the strain of sexual activity can be compared accurately with standard types of physical activity and whether sexual activity is more closely related to episodes of anger or fear.85x85DeBusk, RF. Evaluating the cardiovascular tolerance for sex. Am J Cardiol. 2000; 86: 51F–56F
Abstract | Full Text | Full Text PDF | PubMed | Scopus (124) | Google ScholarSee all References This was a doubleblind, single-dose crossover study involving 41 men with stable coronary artery disease characterized by reproducible stable exertional angina. After taking either 10 mg of vardenafil or placebo, these men underwent treadmill exercise tolerance testing to 5 to 10 METs. Compared with placebo, vardenafil use did not result in a change in exercise treadmill time or time to first awareness of angina but significantly increased the time to ischemic threshold. At peak exercise levels, vardenafil did not cause a change in either heart rate or blood pressure level. This study concluded that 10 mg of vardenafil did not impair the ability of men with stable coronary artery disease to exercise at levels consistent with the exertion associated with sexual intercourse.
Levine GN, Steinke EE, Bakaeen FG, Bozkurt B, Cheitlin MD, Conti JB, Foster E, Jaarsma T, Kloner RA, Lange RA, Lindau ST, Maron BJ, Moser DK, Ohman EM, Seftel AD, Stewart WJ. Sexual activity and cardiovascular disease: a scientific statement from the American Heart Association, Circulation , 2012, vol. 125 (pg. 1058-1072)https://doi.org/10.1161/CIR.0b013e3182447787
Three longitudinal studies have estimated incidence rates of ED in men with diabetes. Unfortunately, none of these studies specifically examined men with type 2 disease. In a cohort of 278 diabetic men with type 1 or type 2 diabetes potent at study entry, the proportion of patients reporting ED at 5-year follow-up was 28%.7 A follow-up analysis of the Massachusetts Male Aging Study, a community-based cohort of men between 40 and 70 years of age, found that the incidence of ED in the diabetic men was 51/1,000 population-years.8 This figure was similar to the 68/1,000 person-years crude incidence rate of ED reported in a study of 1,010 men with diabetes.5 However, new studies need to be carried out in well-characterized populations of men with diabetes in order to better determine the incidence of ED and potential effects of interventions to reduce complications.
Causes of ED may be of primary developmental origin or secondary. Lack of sex hormone in the early developmental stage of male children is the major cause of primary ED. The secondary cause of ED involves arteriosclerosis, diabetes or psychogenic disturbances. Other secondary factors may include hypertension, hyperlipidaemia, obesity and tobacco use. The primary causes of ED are beyond the scope of this review; we will not be discussing the neurovascular mechanisms pertaining to ED and will focus on the relationship between IHD and ED.
Ginkgo Biloba is promoted to treat conditions ranging from hypertension to Alzheimer’s dementia. There is evidence that shows improvement of memory enhancements in the geriatric population (47), improvement in terms of cognitive function via effect on cerebral vasculature (48), improvement of claudication distance and cutaneous ulcers in patients with peripheral vascular disease (49). Ginkgo Biloba extract is proposed to induce NO in endothelial cells and thus causing relaxation of vascular smooth muscles. Animal studies have reported relaxation of rabbit corpus cavernosal smooth muscle cells with the use of Ginkgo Biloba (50). Adverse effects include headaches, major bleeding (in patient who are taking warfarin concurrently) and seizures with reported fatality (36).
Severe testosterone deficiency, known as “hypogonadism,” is present in approximately 2–35% of men with erectile dysfunction.19 However, lesser degrees of deficiency are common, perhaps present in the majority, depending on the definition of “low” applied, the method of measurement, and the parameter being used to define testosterone (total, free, or bioavailable) deficiency.19,20 Most authorities agree that a total testosterone level below 300 ng/dL is clearly low, and that 300–400 ng/dL is low to low-to-normal. Most studies using testosterone replacement for erectile dysfunction have attempted to achieve blood levels of 450–850 ng/dL.
Another study showed a forty percent increase of blood flow to the heart within one year of starting a dietary program designed similar to the one described in my book, The End of Heart Disease. Of pertinent note is that, in the same study, the patients following a high-protein Atkins’ diet decreased blood flow to the heart by forty percent in one year.8 These dangerous high-protein diets are a certain path to erectile impotence and a premature cardiac death.
Combination therapy has proven effective for some men who don’t respond adequately to oral medicines. The idea is to use two drugs with different mechanisms of action for better results. Commonly, sildenafil is used in combination with pellets of alprostadil (synthetic prostaglandin E1) that are inserted into the urethra (the tube in the penis that carries urine from the bladder to the outside of the body). Alprostadil also increases the blood supply to the penis, but by different means.