Erectile dysfunction

Erectile dysfunction (ED), also referred to as impotence, is a form of sexual dysfunction in males characterized by the persistent or recurring inability to achieve or maintain a penile erection with sufficient rigidity and duration for satisfactory sexual activity. It is the most common sexual problem in males and can cause psychological distress due to its impact on self-image and sexual relationships. The term erectile dysfunction does not encompass other erection-related disorders, such as priapism.

The majority of ED cases are attributed to physical risk factors and predictive factors. These factors can be categorized as vascular, neurological, local penile, hormonal, and drug-induced. Notable predictors of ED include aging, cardiovascular disease, diabetes mellitus, high blood pressure, obesity, abnormal lipid levels in the blood, hypogonadism, smoking, depression, and medication use. Approximately 10% of cases are linked to psychosocial factors, encompassing conditions such as depression, stress, and problems within relationships. ED is reported in 18% of males aged 50 to 59 years, and 37% in males aged 70 to 75.

Signs and symptoms

ED is characterized by the persistent or recurring inability to achieve or maintain an erection of the penis with sufficient rigidity and duration for satisfactory sexual activity.

Psychological impact

ED often has an impact on the emotional well-being of both males and their partners.

Causes

Causes of or contributors to ED include the following:

Diets high in saturated fat are linked to heart diseases, and males with heart diseases are more likely to experience ED. By contrast, plant-based diets show a lower risk for ED.
Prescription drugs (e.g., SSRIs, beta blockers, antihistamines, alpha-2 adrenergic receptor agonists, thiazides, hormone modulators, and 5α-reductase inhibitors)
Cavernosal disorders (e.g., Peyronie's disease)
Hyperprolactinemia (e.g., due to a prolactinoma)
Surgery (e.g., radical prostatectomy)
Ageing: after age 40 years, ageing itself is a risk factor for ED, although numerous other pathologies that may occur with ageing, such as testosterone deficiency, cardiovascular diseases, or diabetes, among others, appear to have interacting effects
Kidney disease: ED and chronic kidney disease have pathological mechanisms in common, including vascular and hormonal dysfunction, and may share other comorbidities, such as hypertension and diabetes mellitus that can contribute to ED
Lifestyle habits, particularly smoking, which is a key risk factor for ED as it promotes arterial narrowing. Due to its propensity for causing detumescence and erectile dysfunction, some studies have described tobacco as an anaphrodisiacal substance.
COVID-19: preliminary research indicates that COVID-19 viral infection may affect sexual and reproductive health.

Surgical intervention for a number of conditions may remove anatomical structures necessary to erection, damage nerves, or impair blood supply.

ED can also be associated with bicycling due to both neurological and vascular problems due to compression. The increased risk appears to be about 1.7-fold.

Concerns that use of pornography can cause ED have little support in epidemiological studies, according to a 2015 literature review. According to Gunter de Win, a Belgian professor and sex researcher, "Put simply, respondents who watch 60 minutes a week and think they're addicted were more likely to report sexual dysfunction than those who watch a care-free 160 minutes weekly." A 2026 review shows that simple pornography consumption does not cause erectile dysfunction, the relationship between pornography and ED being much more complex.

In seemingly rare cases, medications such as SSRIs, isotretinoin (Accutane) and finasteride (Propecia) are reported to induce long-lasting iatrogenic disorders characterized by sexual dysfunction symptoms, including erectile dysfunction in males; these disorders are known as post-SSRI sexual dysfunction (PSSD), post-retinoid sexual dysfunction/post-Accutane syndrome (PRSD/PAS), and post-finasteride syndrome (PFS). These conditions remain poorly understood and lack effective treatments, although they have been suggested to share a common etiology.

Rarely impotence can be caused by aromatase being active. See Androgen replacement therapy.

Pathophysiology

Penile erection is managed by two mechanisms: the reflex erection, which is achieved by directly touching the penile shaft, and the psychogenic erection, which is achieved by erotic or emotional stimuli. The former involves the peripheral nerves and the lower parts of the spinal cord, whereas the latter involves the limbic system of the brain. In both cases, an intact neural system is required for a successful and complete erection. Stimulation of the penile shaft by the nervous system leads to the secretion of nitric oxide (NO), which causes the relaxation of the smooth muscles of the corpora cavernosa (the main erectile tissue of the penis), and subsequently penile erection. Additionally, adequate levels of testosterone (produced by the testes) and an intact pituitary gland are required for the development of a healthy erectile system. As can be understood from the mechanisms of a normal erection, impotence may develop due to hormonal deficiency, disorders of the neural system, lack of adequate penile blood supply or psychological problems.

Diagnosis

In many cases, the diagnosis can be made based on the person's history of symptoms. In other cases, a physical examination and laboratory investigations are done to rule out more serious causes such as hypogonadism or prolactinoma. Similarly, performance with manual stimulation, as well as any performance anxiety or acute situational ED, may indicate a psychogenic component to ED.edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR) lists Erectile Disorder (ICD-10-CM code: F52.21) as a diagnosis. According to the DSM, it "is the more specific DSM-5 diagnostic category in which erectile dysfunction persists for at least 6 months and causes distress in the individual." The latest edition of the ICDnamely, the ICD-11lists the condition as Male erectile dysfunction (HA01.1).

Ultrasonography

[[File:Ultrasonography of dilated penile sinusoids during erection.jpg|thumb|Transverse ultrasound image, ventral view of the penis. Image obtained after induction of an erection, 15 min after injection of prostaglandin E1, showing dilated sinusoids (arrows).

Erection can be induced by injecting 10–20 μg of prostaglandin E1, with evaluations of the arterial flow every five minutes for 25–30 min (see image). The use of prostaglandin E1 is contraindicated in patients with predisposition to priapism (e.g., those with sickle cell anemia), anatomical deformity of the penis, or penile implants. Phentolamine (2 mg) is often added. Visual and tactile stimulation produces better results. Some authors recommend the use of sildenafil by mouth to replace the injectable drugs in cases of contraindications, although the efficacy of such medication is controversial.

;Nocturnal penile tumescence (NPT):It is normal for a man to have five to six erections during sleep, especially during rapid eye movement (REM). Their absence may indicate a problem with nerve function or blood supply in the penis. There are two methods for measuring changes in penile rigidity and circumference during nocturnal erection: snap gauge and strain gauge. A significant proportion of males who have no sexual dysfunction nonetheless do not have regular nocturnal erections.

;Penile biothesiometry:This test uses electromagnetic vibration to evaluate sensitivity and nerve function in the glans and shaft of the penis.

;Dynamic infusion cavernosometry (DICC):Technique in which fluid is pumped into the penis at a known rate and pressure. It gives a measurement of the vascular pressure in the corpus cavernosum during an erection.

;Corpus cavernosometry:Cavernosography measurement of the vascular pressure in the corpus cavernosum. Saline is infused under pressure into the corpus cavernosum with a butterfly needle, and the flow rate needed to maintain an erection indicates the degree of venous leakage. The leaking veins responsible may be visualized by infusing a mixture of saline and x-ray contrast medium and performing a cavernosogram. In Digital Subtraction Angiography (DSA), the images are acquired digitally.

;Magnetic resonance angiography (MRA): This is similar to magnetic resonance imaging. Magnetic resonance angiography uses magnetic fields and radio waves to provide detailed images of the blood vessels. The doctor may inject into the patient's bloodstream a contrast agent, which causes vascular tissues to stand out against other tissues, so that information about blood supply and vascular anomalies is easier to gather.

;Erection Hardness Score

Treatment

thumb|upright=1.5| One ad from 1897 claims to restore "perfect manhood. Failure is impossible with our method". The U.S. Federal Trade Commission warns that "phony cures" exist even today.

Treatment depends on the underlying cause. In general, exercise, particularly of the aerobic type, is effective for preventing ED during midlife. Counseling can be used if the underlying cause is psychological, including how to lower stress or anxiety related to sex. Treatments, other than surgery, do not fix the underlying physiological problem, but are used as needed before sex.

Medications

The PDE5 inhibitors sildenafil (Viagra), vardenafil (Levitra) and tadalafil (Cialis) are prescription drugs which are taken by mouth. Additionally, a cream combining alprostadil with the permeation enhancer DDAIP has been approved in Canada as a first line treatment for ED. Penile injections, on the other hand, can involve one of the following medications: papaverine, phentolamine, and prostaglandin E1, also known as alprostadil. Medications to treat ED may cause a side effect called priapism.

Focused shockwave therapy

Focused shockwave therapy involves passing short, high frequency acoustic pulses through the skin and into the penis. These waves break down any plaques within the blood vessels, encourage the formation of new vessels, and stimulate repair and tissue regeneration.

Focused shockwave therapy appears to work best for males with vasculogenic ED, which is a blood vessel disorder that affects blood flow to tissue in the penis. The treatment is painless and has no known side effects. Treatment with shockwave therapy can lead to a significant improvement of the IIEF (International Index of Erectile Function).

Testosterone

Men with low levels of testosterone can experience ED. Taking testosterone may help maintain an erection. Males with type 2 diabetes are twice as likely to have lower levels of testosterone, and are three times more likely to experience ED than non-diabetic men.

Vibrators

The vibrator was invented in the late 19th century as a medical instrument for pain relief and the treatment of various ailments. Sometimes described as a massager, the vibrator is used on the body to produce sexual stimulation. Several clinical studies have found vibrators to be an effective solution for Erectile Dysfunction. Examples of FDA registered vibrators for erectile dysfunction include MV.Health's Tenuto and Reflexonic's Viberect.

Surgery

Often, as a last resort, if other treatments have failed, the most common procedure is prosthetic implants which involves the insertion of artificial rods into the penis. Many products are advertised as "herbal viagra" or "natural" sexual enhancement products, but no clinical trials or scientific studies support the effectiveness of these products for the treatment of ED, and synthetic chemical compounds similar to sildenafil have been found as adulterants in many of these products. The FDA has warned consumers that any sexual enhancement product that claims to work as well as prescription products is likely to contain such a contaminant. A 2021 review indicated that ginseng had "only trivial effects on erectile function or satisfaction with intercourse compared to placebo".

History

thumb|An unhappy wife is complaining to the [[qadi about her husband's impotence. Ottoman miniature.]]

Attempts to treat the symptoms described by ED date back well over 1,000 years. In the 8th century, males of Ancient Rome and Greece wore talismans of rooster and goat genitalia, believing these talismans would serve as an aphrodisiac and promote sexual function. In the 13th century, Albertus Magnus recommended ingesting roasted wolf penis as a remedy for impotence.

The first major publication describing a broad medicalization of sexual disorders was the first edition of the Diagnostic and Statistical Manual of Mental Disorders in 1952. In the early 20th century, medical folklore held that 90-95% of cases of ED were psychological in origin, but around the 1980s research took the opposite direction of searching for physical causes of sexual dysfunction, which also happened in the 1920s and 30s. Physical causes as explanations continue to dominate literature when compared with psychological explanations .

Treatments in the 80s for ED included penile implants and intracavernosal injections. John R. Brinkley initiated a boom in male impotence treatments in the U.S. in the 1920s and 1930s, with radio programs that recommended expensive goat gland implants and "mercurochrome" injections as the path to restored male virility, including operations by surgeon Serge Voronoff.

Modern drug therapy for ED made a significant advance in 1983, when British physiologist Giles Brindley dropped his trousers and demonstrated to a shocked Urodynamics Society audience showing his papaverine-induced erection. The current most common treatment for ED, the oral PDE5 inhibitor known as sildenafil (Viagra) was approved for use for Pfizer by the FDA in 1998, which at the time of release was the fastest selling drug in history. Sildenafil largely replaced SSRI treatments for ED at the time and proliferated new types of specialised pharmaceutical marketing which emphasised social connotations of ED and Viagra rather than its physical effects.

Anthropology

Anthropological research presents ED not as a disorder but, as a normal, and sometimes even welcome sign of healthy aging. Wentzell's study of 250 Mexican males in their 50s and 60s found that "most simply did not see decreasing erectile function as a biological pathology". The males interviewed described the decrease in erectile function "as an aid for aging in socially appropriate ways". By relying on a wholly medical approach, Western biomedicine can become blindsided by bodily dysfunctions which can be understood as appropriate functions of age, and not as a medical problem. Anthropologists understand that a biosocial approach to ED considers a person's decision to undergo clinical treatment more likely a result of "society, political economy, history, and culture" than a matter of personal choice. The condition is also on occasion called phallic impotence. Its antonym, or opposite condition, is priapism.

References

External links