Erectile dysfunction (ED) affects about 50% of men over 40 and is even more common as men age. According to a study on the impact of ED, men's most common initial reaction to ED diagnosis is a sense of emasculation. In addition, ED causes severe distress, with marked effects on self-esteem and relationships. However, whether the cause of your ED is psychological, physical, or mixed, ED is treatable. If you are among the many who have symptoms of ED, a phone call to your doctor is the first step toward a return to quality erections.
Erectile dysfunction occurs when a person cannot attain or maintain a sufficient erection for sexual intercourse. Erectile function depends on many factors, including the correct balance of vasoactive substances, endocrine factors, neurotransmitters, and tissue fibroelastic properties. The imbalance of these factors can lead to difficulties in maintaining proper erectile function.
Testosterone (T) treatment in hypogonadal men with ED improves sexual attitudes and performance in 61% of patients. Moreover, T therapy is changing the lives of men who suffer from ED and giving them back the vitality they have missed.
What is hypogonadism?
The clinical diagnosis of hypogonadism occurs when symptoms accompany low T (less than 300 ng/dL). Signs and symptoms of hypogonadism include weakness, fatigue, decreased energy, low libido, increased abdominal fat, and ED.
Hypogonadism is associated with aging, obesity, hyperlipidemia, metabolic syndrome, diabetes, hypertension, and coronary artery disease. By age 70, 30% of men have low T levels. Erectile dysfunction is usually not an issue until the T level reaches 200 ng/dL. However, libido may be affected at higher T levels.
What causes erectile dysfunction?
Sexual arousal is a complicated process that involves your brain, hormones, nerves, muscles, and blood vessels; dysfunction in any of these can lead to ED. Physical or psychological issues can cause ED.
Physical issues such as heart disease, high cholesterol, high blood pressure, hormonal imbalances, diabetes, obesity, and smoking can all cause ED. On the other hand, depression, anxiety, stress, relationship problems, and other mental health concerns can interfere with sexual feelings, which may cause or worsen ED. Erectile dysfunction is often a combination of physical and mental issues, so it is vital to understand one's physical and psychological state to understand the underlying cause of ED.
While T plays a role in sexual function, many men with low T can get erections just fine, while many men with healthy T levels have difficulty getting and maintaining an erection. Low T and ED, while associated, are not cause and effect.
In addition, ED in patients with low T may be due to low libido, fatigue, mood changes, cellular changes in penis structure, or other factors. In addition, side effects of low T include weight gain, which can make men feel embarrassed or self-conscious about their appearance, making it difficult to partake in sexual activity.
Erections and the role of testosterone
An erection is a hormone-mediated vascular event triggered by sensory or direct stimulation. An erection occurs when blood flows into the corpora cavernosa (erection bodies) and gets trapped there. Erectile dysfunction may occur if blood has problems getting to or staying in the erection bodies. In addition, nitric oxide (NO) is a significant mediator of erections, initiating smooth muscle relaxation after sexual stimulation.
Testosterone helps preserve the synthesis and release of essential enzymes and the structure and function of the corpora cavernosa, which directly impacts erectile function. Also, T is involved in all steps of the erection process by affecting the structure, function, and nerves of the corpora cavernosa. Finally, T is involved in the cellular mechanisms of erection and detumescence (return of the penis to a flaccid state).
A study compared the difference in T levels in men with and without ED and found that patients with ED had lower T at all phases of the erection cycle. The difference between the cavernous T concentration and the systemic concentration in the flaccid stage in healthy subjects was 30% lower compared with 13% lower in patients with ED.
Results of another study of 52 men with ED suggest a positive correlation between free T with vessel dilation, penile elasticity, and cavernous artery compliance. In addition, this study indicates a threshold level of free T necessary for smooth muscle relaxation for adequate erections.
Erectile dysfunction is more common with increasing age and affects about 70% of men older than 70. The ratio of collagen to elastic fibers in the corpora cavernosa increases with age, suggesting this fibrotic process is a possible cause of ED in older men with low T.
Correlation between low testosterone and erectile dysfunction
Numerous studies have examined the relationship between T levels and erectile function. Men with low T have a greater prevalence of ED when compared to men with normal T levels.
In an extensive study of 434 men between 50 and 86 years old, the incidence of ED occurred when T levels reached a mean of 231 ng/dL.
Additional studies measured the effects of low T on ED by looking at men with prostate cancer who underwent either castration, or androgen deprivation therapy (ADT) to treat their disease. Castration resulted in ED in 50% of men. Results were similar for those on ADT. After discontinuing ADT, T levels normalized, and there was a reproducible return of sexual function.
Many studies demonstrate positive results when treating men with hypogonadism and ED with TRT. The U.S. National Institute of Aging funded T trials of seven 52-week studies that included 788 men older than 65 with hypogonadism. Results demonstrated that compared with placebo, TRT increases erectile function, sexual interest, and sexual activity proportionally to the increase in T levels.
Treatment guidelines for men with ED
The American Urology Association (AUA) and the European Association of Urology guidelines recommend evaluating T levels in men with ED to determine whether hypogonadism influences the disease process.
Management of ED in patients with hypogonadism
Treatment for ED depends on the cause and severity and starts with identifying and treating any underlying health condition that may be contributing to ED. There is evidence that hypogonadism responds to lifestyle measures and optimization of comorbidities to some extent. Such interventions, if achievable, may have health benefits beyond the benefits of raising T.
Therefore, treating the underlying causes of hypogonadism and related symptoms initially or in conjunction with TRT may have added benefits. For example, in obese men with ED, TRT will likely improve their symptoms of ED, but significant weight loss will also decrease their risk of many comorbid chronic diseases.
If the cause of ED is low T, TRT is an effective treatment for ED, especially when there is decreased libido, depressed mood, and increased fatigue. TRT improves ED in 36% and penile vascular parameters in 42% of patients.
Doctors monitor TRT by the patient's overall satisfaction with treatment, sexual activity frequency, and the IIEF patient questionnaire.
All extensive studies show that TRT effectively improves sexual function in hypogonadal men. For example, a 2005 study using data from 17 studies compared the effects of TRT on different sexual function domains. TRT moderately improved erectile function scores and overall sexual satisfaction, successful sexual intercourse, and sexual thoughts in men with baseline low T.
In a 2017 study of 2298 men with low T, TRT significantly improved erectile function compared with a placebo. In addition, men with severe hypogonadism had even more significant improvement in ED than men with less severe hypogonadism.
In a large, international study, TRT significantly improved sexual desire, ED, and quality of life at a 12-month follow-up; patients with moderate or severe ED decreased from 67% to 19%. Studies with even longer follow-ups confirm the benefits of TRT on ED.
Combination of testosterone and phosphodiesterase-5 inhibitor therapy
Treatment with T and phosphodiesterase-5 inhibitors improves the symptoms of ED for many people who do not respond to either treatment alone. Studies suggest that combination therapy can be more effective than treatment with either T or a phosphodiesterase-5 inhibitor.
For patients with a poor response to PDE-5 inhibitors, adding TRT converts up to half of hypogonadal men who do not respond to the PDE-5 inhibitor. The mean erectile function significantly increased in all patients on combination therapy who had either no or minimal response to the PDE-5 inhibitor; this is important since up to 50% of men have no response to PDE-5 inhibitors alone.
Conversely, in men who do not respond to T monotherapy, adding a PDE-5 inhibitor can improve ED. In one study, adding a PDE-5 inhibitor to patients who did not improve on TRT alone resulted in 92% of men reporting at least some return of erectile function.
While discussing ED may be uncomfortable initially, remember that it's a common and often treatable condition. Discussing your concerns with your PCP is an excellent place to start. However, if you don't feel comfortable or need more help, you may want to see a specialist.
A urologist is a doctor who specializes in the health of the urinary system and the male reproductive system. Endocrinologists treat the body's endocrine system, which controls hormones that affect most body systems.
Finally, many healthcare providers are available for online chats or virtual appointments. Remember that you are not alone; your doctor likely has many other patients with similar healthcare concerns.