- What is male sexual dysfunction (erectile dysfunction, impotence)?
- Statistics on male sexual dysfunction
- Risk factors for male sexual dysfunction
- Progression of male sexual dysfunction
- Symptoms of male sexual dysfunction
- Clinical examination of male sexual dysfunction
- How is male sexual dysfunction diagnosed?
- Prognosis of male sexual dysfunction
- How is male sexual dysfunction treated?
What is male sexual dysfunction (erectile dysfunction; impotence)?
Erectile dysfunction is the inability to develop or maintain an erection that is rigid enough to allow penetration of the vagina, and therefore functional sexual intercourse. Generally, the term erectile dysfunction is applied if this occurs frequently (75% of the time) over a significant period if time (several weeks to months). If this is the case, the term impotence may also be used.
Erectile dysfunction may present in different ways. Some men are completely unable to develop an erection. Some may develop an erection that does not remain rigid enough to allow satisfactory intercourse.
There are several causes of erectile dysfunction, including certain drugs (prescription and non prescription), psychological causes, and problems with the hormones, nerves or blood vessels that supply the penis.
Other problems with male sexual function include a lack of sexual drive or desire (libido), problems with ejaculation (ejaculatory dysfunction), and lack of pleasurable sensation (orgasm) during sex. These problems will not be discussed in detail.
Erectile dysfunction is a common problem. It is important that men who experience erectile dysfunction discuss it with their doctor, because the condition can have a negative impact on relationships and self esteem; serious underlying causes need to be excluded; and effective treatment is available.
Statistics on male sexual dysfunction
Erectile dysfunction is estimated to effect 150 million men worldwide, and more than one million men in Australia.Overall, 25% of Australian men report erectile dysfunction and 8.5% report severe erectile dysfunction.
In one study, 9.6% reported ‘occasional’ erectile dysfunction, 8.9% reported erectile dysfunction occurring ‘often’, and 18.6% reported erectile dysfunction occurring ‘all the time’. Of these, only 11.6% had received treatment.In another study, only 14.1% of men reported that they had received treatment, despite experiencing erectile dysfunction for longer than 12 months.
Erectile dysfunction is never ‘normal’, however it does become more common and more severe as men age. One Australian study reported the rate of erectile dysfunction in different age groups:
- 20-29 years: 9.2%;
- 30-39 years: 8.4%;
- 40-49 years: 13.1%;
- 50-59 years: 33.5%;
- 60-69 years: 51.5%;
- 70-79 years: 69.2%;
- 80+ years: 76.2%.
Due to the ageing Australian population, erectile dysfunction is expected to become more common.
There is no difference between the prevalence of erectile dysfunction between “white-collar” and “blue-collar” workers in Australia.
Sexual dysfunction associated with cancer
Between 10 and 88% of patients diagnosed with cancer experience sexual problems following diagnosis and treatment. The prevalence varies according to the location and type of cancer, and the treatment modalities used. Sexuality may be affected by chemotherapy, alterations in body image due to weight change, hair loss or surgical disfigurement, hormonal changes, and cancer treatments that directly affect the pelvic region.
Sexual problems are reported in many patients with prostate and testicular cancer. They are also reported in patients with cancer that does not directly effect sexual organs, including lung cancer (48% of patients), Hodgkin’s disease (50%), and laryngeal (%60) and head and neck cancers (39-74%).
For more information, see Sexual Difficulties Associated with Cancer in Men.
Risk factors for male sexual dysfunction
The predisposing factors for erectile dysfunction are as follows:
- Medical conditions such as diabetes mellitus and cardiovascular disease;
- Neurological conditions including or arising from dementia, multiple sclerosis, stroke, or spinal cord or back injury;
- Pelvic trauma, prostate surgery, previous priapism, prolonged bike riding (> 4 hours/week, depending on seat and posture);
- Depression and stress;
- High blood pressure;
- Increased cholesterol;
- Certain drugs (some antidepressants, particularly SSRIs; diuretics; and others);
- Alcohol and recreational drugs such as cocaine and heroin may initially stimulate sexual arousal, however long term use has been shown to lead to erectile dysfunction.
If a man has the risk factors for cardiovascular disease during middle age (smoking, obesity, high cholesterol), he is at an increased risk of developing erectile dysfunction.
Exercise has been shown to have a protective effect.
Progression of male sexual dysfunction
Around one third of men who experience erectile dysfunction find that, without treatment, it becomes worse over time. Around a third of men find that erectile dysfunction improves without treatment.
Around half of men with severe erectile dysfunction remain impotent in the long term without treatment.
These figures vary depending on the cause of the erectile dysfunction. Even if men choose not to pursue treatment for erectile dysfunction, it is important that they be investigated by a doctor, as erectile dysfunction may indicate an increased risk of cardiovascular disease.
Symptoms of male sexual dysfunction
Temporary failure of erection is very common and is likely to resolve. If ongoing erectile dysfunction develops, the impact on relationships and self-esteem can be devastating. Men who suffer from erectile dysfunction are known to experience significant psychological distress. It is believed that sexual self-consciousness leads to:
- Increased appearance related anxieties;
- Interferes with attention, focus and concentration;
- Impairs physical performance; and
- Reduces awareness of our physiological arousals leading to sexual dysfunction.
This improves when erectile dysfunction is successfully treated.
While studies are limited, it has been shown that male sexual dysfunction can also negatively impact the sexual function of female partners. A study comparing the sexual function of women with partners with erectile dysfunction to those without showed that sexual arousal, lubrication, orgasm, satisfaction, pain and total score were significantly lower in those who had partners with erectile dysfunction. Later in that study, a large proportion of the men with erectile dysfunction underwent treatment. Following treatment, sexual arousal, lubrication, orgasm, satisfaction and pain were all significantly increased. It was concluded that female sexual function is impacted by male erection status, which may improve following treatment of male sexual dysfunction.
It is essential to discuss erectile dysfunction with your doctor, so any serious underlying causes can be excluded and treatment options can be discussed. Many men are embarrassed discussing this issue with their doctor, or even their partner. Open communication with your doctor, and in your relationship, is important for effectively managing this common problem.
Effective treatment for erectile dysfunction is available, and for most men will allow the return to a fulfilling sex life. The side effects of the treatment for erectile dysfunction vary depending on the treatment that is used. Some may interrupt the spontaneity of sexual activity. For example, PDE-5 inhibitors typically need to be taken one hour before sex. Side effects may include headaches, indigestion, vasodilation, diarrhoea and blue tinge to vision. Other treatments such as penile injections may cause pain at the injection site, or an erection that will not go down. Treatment options need to be carefully discussed with your doctor to determine which one is best suited to you.
Clinical examination of male sexual dysfunction
Following a detailed discussion about the history of erectile dysfunction and its risk factors, your doctor will examine the testicles and penis to help determine the cause of erectile dysfunction. Your doctor will check reflexes and pulses in the area to see if problems with blood vessels or nerves are contributing to the erectile dysfunction. If necessary, your doctor will order tests to help diagnose erectile dysfunction.
How is male sexual dysfunction diagnosed?
Diagnosis is based on information provided to the doctor regarding the history of erectile dysfunction (how quickly it came on, how often it occurs, etc), the assessment of risk factors, and whether erections still occur overnight while a man is asleep. It is normal for a man to have 3-5 full erections overnight during REM sleep.
In order to establish whether normal erections are occurring overnight (nocturnal erections), the doctor may organise nocturnal penile tumescence (NPT) testing. This involves wearing a monitor overnight in your own home. The data from this monitor is then assessed to analyse how often erections occurred, how long they lasted, and how rigid and large the penis was during the erections. If NPT testing is normal, the cause of erectile dysfunction is usually psychological. If not, further testing of the blood flow in the genital area may be required to see if there is blockage or leakage. The doctor may also organise a blood test of levels of hormones such as testosterone, prolactin and thyroid stimulating hormone to see if these are contributing to the erectile dysfunction.
Prognosis of male sexual dysfunction
For the great majority of men, erectile dysfunction can be effectively treated.
It is essential that if you experience erectile dysfunction, you discuss it with your doctor. Serious underlying causes need to be excluded. Many treatment options are available, and your doctor can help you decide which one is most appropriate for you.
Some causes of erectile dysfunction such as hormonal problems or anxiety may be cured completely with treatment and/or therapy. Even if the underlying cause cannot be cured, medication may still allow a satisfactory erection. Ignoring the problem tends not to make it better, and can have a significant impact on relationships and self-esteem.
How is male sexual dysfunction treated?
Before starting treatment for erectile dysfunction, a doctor needs to check there is no underlying cardiovascular disease, and do other checks to determine the cause of the erectile dysfunction.
The most common treatment for erectile dysfunction is drugs known as phosphodiesterase-5 (PDE-5) inhibitors. These include tadalafil (Cialis), vardenafil (Levitra), and sildenafil citrate (Viagra). These are effective for about 75% of men with erectile dysfunction. They are tablets that are taken around an hour before sex, and last between 4 and 36 hours. Sexual stimulation is required before an erection will occur. The PDE-5 inhibitors cause dilation of blood vessels in the penis to allow erection to occur, and help it to stay rigid. Men using nitrate medication (e.g. GTN spray or sublingual tablets for angina) should not use PDE-5 inhibitors.
If testosterone levels are found to be low, erectile dysfunction should initially be treated with testosterone replacement therapy.
If PDE-5 inhibitors are not suitable or don’t work, other therapies include injections into the base of the penis, which cause flow of blood into the penis and a fairly immediate erection that lasts around an hour. The drugs injected are alprostadil (Caverject and Erectile dysfunctionex) and Invicorp (VIP and phentolamine). Alprostadil may also be inserted as a gel into the opening of the penis. This is not suitable if your partner is pregnant.
Vacuum erection devices use a pump mechanism to create negative pressure around the penis, encouraging it to become erect. An elastic device is then placed around the base of the penis to help maintain the erection.
As a last resort, penile prostheses may be considered. Malleable rods and inflatable versions are available. This option involves surgery to insert the device, and so has more risks than the other treatments.
Surgery to correct blocked or leaking blood vessels used to be popular, but is not very effective for long term erectile function unless it is being done to correct traumatic vascular damage in young men.
Erectile dysfunction experienced by obese men has been shown to improve considerably with weight loss and exercise.Other lifestyle changes that improve erectile dysfunction include reducing the use of alcohol, recreational drugs and cigarettes.
If erectile dysfunction is found to be caused by anxiety or depression, psychotherapy may be an effective treatment on its own or in combination with certain drugs (e.g. antidepressants). Sexual therapy counsellors specialise in this field.
If men are found to be taking a medication that is known to cause erectile dysfunction, their doctor may prescribe an alternative, equally effective therapy.
|For more information on erectile dysfunction, types, causes and treatments of erectile dysfunction, and tips for dealing with it, see Erectile Dysfunction.|
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