It goes without saying that an erect penis is a symbol of a man’s virility and sexual prowess. According to a 2015 study published in the Asian Journal of Andrology, it is estimated that the prevalence of erectile dysfunction (ED) will be 322 million by the year 2025. It also revealed that the prevalence of ED was 1%–10% in men younger than 40 years, 2%–9% among men between 40 and 49 years, 20%–40% among men between 60 and 69 years and more than 50% in men older than 70 years of age. The condition mainly affects men older than 40 years and the prevalence of ED increases with age. But what is erectile dysfunction? What are the causes of impotence? Are you at risk of ED? Well, all your questions about erectile dysfunction answered.
What Is Erectile Dysfunction?
Erectile dysfunction, as the name suggests, is a medical condition that causes an inability to achieve or maintain an erection for satisfactory sexual performance. This could be attributed to dysfunction in two major aspects of males erection which is reflex erection and psychogenic erection.
Reflex/organic erection is achieved on directly touching the penile shaft. This type of erection is mainly under the control of the peripheral nerves and lower parts of the spinal cord.
Psychogenic erection is achieved because of erotic or emotional stimuli and is under the control of the limbic system of the brain.
What Causes An Erection?
The penis remains in its flaccid state when the smooth muscle is contracted. These smooth muscles allow only a small amount of arterial blood flow which is basically for nutritional purposes. When sexually stimulated, there is a release of neurotransmitters namely nitric oxide (NO) from the nerve terminals in the penis. This causes relaxation of the smooth muscles along with dilation of the arteries due to increased blood flow to the penile region. This causes the penis to become erect and rigid. Erection ends when the smooth muscles contract and allow the accumulated blood to flow out through the penile veins.
What Causes Erectile Dysfunction?
There are many possible causes of erectile dysfunction that range from vascular and neurogenic factors to psychological and hormonal problems.
Psychogenic erectile dysfunction: Psychogenic erection is a result of audiovisual stimuli or fantasy. Impulses from the brain modulate the spinal erection centers to activate the erectile process. Hence, psychological conditions such as stress, depression, and anxiety are commonly associated with psychogenic erectile dysfunction. These conditions are generally related as heightened anxiety which causes an inability to achieve and maintain an erection before or during sexual relations. and It is an important factor to consider when evaluating and managing men with ED.
Neurogenic erectile dysfunction: It is caused due to a dysfunction in the nerve signaling to the corpora cavernosa, smooth muscle in the penile region. This could be due to a spinal cord injury or conditions such as multiple sclerosis, Parkinson disease, lumbar disc disease, radical pelvic surgery, and diabetes. This inhibits the central nervous system (CNS)-mediated control of the erection, which causes a reduction in NO load, which in turn affects erection.
Vasculogenic erectile dysfunction: The reduced blood inflow and arterial insufficiency caused due to vascular disease and endothelial dysfunction can lead to erectile dysfunction. It is the most common etiology of organic erectile dysfunction which is due to an underlying vascular disorder. The risk of developing vasculogenic erectile dysfunction is increased in men with vascular diseases such as hypertension, diabetes, and dyslipidemia. Vasculogenic ED is secondary to reduced elasticity of arterial wall caused due to an increase in blood pressure.
Iatrogenic erectile dysfunction: The most common iatrogenic cause of erectile dysfunction is radical pelvic surgery. Generally, the damage that occurs during these procedures is primarily neurogenic in nature. This is because of the close relationship between the cavernous nerves and the pelvic organs, surgery on these organs is a frequent cause of impotence. Pelvic fractures can also cause erectile dysfunction in a similar manner. The incidence of iatrogenic impotence from radical prostatectomy is reported to be 43% to 100% and that due to perineal prostatectomy for benign disease was found to be 29% .
Moreover, various medications have also been shown to be associated with the development of erectile dysfunction. Certain medications that are most commonly associated with erectile dysfunction are diuretics and β-blockers, psychotherapeutics, anti-androgens, anti-ulcer drugs, opiates, and digoxin.
Hormonal erectile dysfunction: Androgens are considered the major hormonal regulator of penile development and physiology. Androgens influence the growth and development of the male reproductive tract and secondary sex characteristics; their effects on libido and sexual behavior are well established. According to a study  testosterone enhances sexual interest, increases the frequency of sexual acts and nocturnal erections. However, it has little or no effect on fantasy-induced or visually induced erections. Part of the erectile response to testosterone is mediated through sexual desire (the male sex drive depends on testosterone), but studies have documented a direct role of testosterone on cavernous smooth muscle cells, involving NO.
The factors that can cause or increase the risk of erectile dysfunction include:
-Certain medications including some antihypertensives and antidepressants
As erectile dysfunction can be caused by one or several of these factors, it is important to talk to your doctor to know the exact cause and treat these underlying health problems.
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