Men’s health 2018: BPH, prostate cancer, erectile dysfunction, supplements
ABSTRACT
This review describes the latest research and guidelines for 4 topics in men’s health commonly addressed by primary care physicians: the diagnosis and treatment of benign prostatic hyperplasia (BPH), prostate cancer, and erectile dysfunction and the evidence concerning the use of dietary supplements in men.
KEY POINTS
- The combination of an alpha-blocker and a 5-alpha reductase inhibitor is an effective regimen for BPH. Withdrawing the alpha-blocker from the combination can be considered if symptoms have been well controlled after 1 year of combination therapy.
- A new look at 2 large trials of prostate-specific antigen screening strengthened evidence that testing in the right patient population can reduce deaths from prostate cancer, but a third recently published trial found no benefit to 1-time screening.
- Magnetic resonance imaging offers a better method than ultrasonography-guided biopsy to triage patients thought to be at high risk of prostate cancer and tends to limit costly overtreatment of disease that likely would not cause death.
- Erectile dysfunction is often associated with chronic disease and may suggest the need to screen for cardiovascular disease.
MANAGEMENT OF ERECTILE DYSFUNCTION
A 62-year-old man with hypertension, hyperlipidemia, peripheral artery disease, and type 2 diabetes presents for a 6-month follow-up. His medications include aspirin, metformin, lisinopril, and atorvastatin, all of which he takes without problems. Over the past several months, he has noticed that his erections are not adequate for sexual intercourse. He recently heard that a generic version of sildenafil has just become available, and he wonders if it might benefit him.
Erectile dysfunction is common, associated with chronic diseases
Erectile dysfunction, ie, persistent inability to obtain and maintain an erection sufficient to permit satisfactory sexual intercourse,25,26 is estimated to affect nearly 20% of men over the age of 20 and 75% of men over the age of 75.27
In age-adjusted models, erectile dysfunction has been shown28 to be associated with:
,- History of cardiovascular disease (odds ratio [OR] 1.63, 95% CI 1.02–2.63)
- Diabetes (OR 3.90, 95% CI 2.16–7.04)
- Treated hypertension vs no hypertension (OR 2.22, 95% CI 1.30–3.80)
- Current smoking vs never smoking (OR 1.63, 95% CI 1.01–2.62)
- BMI greater than 30 kg/m2 vs less than 25 kg/m2 (OR 1.80, 95% CI 1.03–3.14).
Because of the strong association between cardiovascular disease and erectile dysfunction, the presence of one often suggests the need to screen for the other.29 While tools such as the International Index of Erectile Function (IIEF-5) have been developed to evaluate erectile dysfunction, it is most often diagnosed on the basis of clinical impression, while validated assessment methods are reserved for clinical trials.28
Multiple causes of erectile dysfunction
Erectile dysfunction arises from inadequate penile tissue response to a sexual signal. The response can be disrupted at several points. For example, damage to vascular smooth muscle cells (eg, from age or obesity) and endothelial cells (from smoking or diabetes) and narrowing of the vascular lumen (from atherosclerosis or hypertension) have all been shown to impair engorgement of the corpus cavernosum.30 In addition, denervation from prostate surgery or spinal trauma and psychogenic causes should be recognized in discussions with patients.
Drugs for erectile dysfunction
Pharmacologic management of erectile dysfunction includes oral, sublingual, intracavernosal, and intraurethral therapies.31 Treatment in primary care settings usually includes addressing underlying chronic diseases32 and prescribing phosphodiesterase-5 inhibitors (sildenafil, tadalafil, vardenafil, and avanafil). These drugs work by increasing local concentrations of cyclic guanosine monophosphate in the corpus cavernosum to induce vasodilation.33
While these 4 drugs are still patent-protected, a manufacturer has been allowed to introduce a generic version of sildenafil into US markets, and a generic version of tadalafil is expected to be available soon.
Sildenafil, tadalafil, and vardenafil have been studied and found to have some degree of effectiveness in erectile dysfunction caused by damage to the penile vasculature, denervation, and spinal cord injury.34 All drugs of this class have adverse effects including headache, facial flushing, and nasal congestion, but the drugs are generally well tolerated.35
Sildenafil and tadalafil improve IIEF-5 scores by a similar margin, raising scores on the erectile domain subsection from approximately 14 of a possible 30 to approximately 24 of 30 in a trial of both drugs.36 However, multiple crossover studies comparing the 2 drugs have shown that nearly 75% of patients prefer tadalafil to sildenafil,36,37 perhaps because of tadalafil’s longer duration of action.34
There is little evidence to suggest that vardenafil is more effective or more often preferred by patients than tadalafil or sidenafil.34,38 And though data on the newest drug on the market, avanafil, are limited, a meta-analysis concluded that it may be less effective than tadalafil and without significant differences in terms of safety.39
Other treatments
Lifestyle modifications, especially smoking cessation and exercise, have been shown to reduce the risk of erectile dysfunction with varying effect sizes across studies.40–42 Moreover, factors such as obesity, alcohol use, and smoking may cause irreversible harm, and thus a healthy lifestyle should be encouraged.41
While there is only weak evidence for the use of psychological interventions alone for treating most types of erectile dysfunction, one meta-analysis found that the combination of psychological intervention and a phosphodiesterase-5 inhibitor improved sexual satisfaction more than drug therapy alone.43
Erectile dysfunction: Take-home points
- Erectile dysfunction is common, affecting nearly 20% of men over the age of 20 and over 75% of men over the age of 75.
- Erectile dysfunction is often associated with chronic disease and may suggest the need to screen for cardiovascular disease.
- Treating underlying chronic diseases may help, and phosphodiesterase-5 inhibitors are effective; tadalafil may be most often preferred.
