Erectile dysfunction (ED) is defined as trouble getting or keeping an erection that’s firm enough for sexual intercourse. Patients with ED may also experience other symptoms including premature or delayed ejaculation, low energy, being easily fatigued, and passiveness. According to the Urology Care Foundation, ED is the most common sex problem affecting as many as 30 million American men, about 50% of men over the age of 40. ED can occur from health problems such as physical conditions, emotional issues, or both.
A physical cause of ED can occur when there is not enough blood flow into the penis or when the parasympathetic and somatotropic nervous function is disturbed. This can occur due to many different health issues including the heart, hormones and the kidneys. Atherosclerosis, hardening of the arteries, can cause a lack of blood to the male sex organs through the narrowing of the arteries. The arteries that branch from the abdomen to the penis can be affected therefore causing the lack of blood flow. Vascular disease can cause ED in as many as 50% to 70% of men who have it. Artery hardening can begin in the lower body with leg cramping and eventually ED as one of the first signs. Typically, a heart attack comes 3 to 5 years after the ED has begun.
Testosterone is the key male sex hormone that regulates a number of processes in the male body including fertility, muscle mass, fat distribution and the development of male sexual characteristics. Testosterone levels decline with age and it has been viewed as the cause of ED. It is believed that ED can occur when testosterone levels drop below a certain threshold. When this threshold is reached, additional amounts do not further increase the frequency, amplitude, or rigidity of an erection.1
Testosterone has been widely used as an important therapy for ED. However, Testosterone therapy has various risks such as worsening sleep apnea, acne, stimulating noncancerous growth of the prostate, limiting sperm production, and stimulating too much red blood cell production, a condition called erythrocytosis. Erythrocytosis can cause symptoms of fatigue, headaches, light-headedness, nosebleeds, breathing problems and many other issues. Having too many red blood cells can make the blood thicker and lead to blood clots and other complications such as a heart attack or stroke. Erythrocytosis also increases the risk of leukemia and other types of blood cancers.
Cortisol is a steroid hormone that regulates a wide range of vital processes throughout the body, including metabolism and the immune response. It also has a very important role in helping the body respond to stress. Cortisol levels rise with age after 40 years old. Research studies have shown that cortisol levels negatively correlate with erectile function. High cortisol levels can disrupt not only the male libido but can also cause erectile dysfunction. The negative effect of cortisol on erectile function occurs because cortisol narrows the arteries and causes blood flow restriction.5
The initiation, maintenance, and rigidity of a penile erection are under parasympathetic and somatotropic control. High cortisol levels activate the sympathetic nervous system which interrupts the parasympathetic and somatotopic activity. Sympathetic pathways are anti-erectile because the sympathetic nervous activity has a restraining effect on erections. Switching off the activity of the sympathetic nervous system enhances erections. 2
Kidney diseases and adrenal deficiency can cause ED. ED is a common condition among male chronic kidney disease patients. Its prevalence is estimated to be approximately 80%. It is caused by the reduction of sex hormones in these patients.
Psychological factors are responsible for about 10%-20% of ED cases. The most common psychological causes of ED include stress, anxiety, and depression. Depression affects a person physically and psychologically. Depression can cause ED even when a man is completely comfortable in sexual situations.
Cortisol is a stress hormone released by the adrenal glands. Our brain triggers cortisol release in response to many different kinds of stress through the activation of the hypothalamic-pituitary-adrenal axis. When cortisol levels are too high for too long, it can cause ED. People with depression tend to have reduced levels of serotonin in the brain and elevated levels of cortisol in their bloodstream. Besides emotional stress, the stress from chronic diseases such as diabetes, high blood pressure, Parkinson’s, cancer, injury or surgery can also cause elevated cortisol levels. Smoking, alcohol, drugs, and many prescription medications can also cause a cortisol level increase and heighten the risk of ED.
Stress and anxiety can also interrupt how the brain sends messages to the penis and interrupts blood flow. Experiencing ED can cause further stress and lead to behavioral changes that can further aggravate ED. Post-traumatic stress disorder (PTSD) has shown to cause hypersensitivity of cortisol receptors which augment the effect of cortisol. A study with veterans who suffered from post-traumatic stress disorder (PTSD) showed that PTSD increased the risk of sexual dysfunction by more than three times. 4
