What are the causes of erectile dysfunction?
The prevalence of ED increases with age: between 40 to 70 years of age the probability of suffering from ED triples, from 5% to 15%.
Cardiovascular risk factors
The most important cardiovascular risk factors are: high blood pressure, hypercholesterolemia, diabetes mellitus, obesity, tobacco consumption and sedentary life style. All of these cause considerable damage to the arteries of the human body, including the arteries of the penis, up to the point that having ED, particularly if it appears after 40 years of age, must be considered an alarm sign since it increases the risk of suffering cardiovascular disease in the future.
Any disease that affects the erector nerves or the spinal or brain centres of the erection will cause ED: multiple sclerosis, paraplegia, cerebrovascular accidents, diabetes mellitus, chronic renal insufficiency, Parkinson’s disease, nocturnal apnea, injuries to the pelvis, radiotherapy of the pelvis, rectal surgery and radical prostatectomy and cystectomy.
Tobacco and alcohol
Tobacco consumption, both active and passive, produces arteriosclerotic lesions in the cavernosal arteries, altering the arterial flow of the penis, which prevents proper relaxation of the trabecular smooth muscle and affects the venous closure mechanism. If consumption is equal to or greater than 20 cigarettes a day, the risk of ED is greatly increased.
Acute alcohol consumption reduces sexual desire, producing temporary ED and delaying ejaculation. Chronic alcoholism causes chronic liver disease, which entails a reduction in the levels of testosterone and an increase in the levels of estrogens, damaging in turn the nerves that control the erection. On the other hand, chronic alcohol consumption reduces the brain’s production of oxytocin and consequently alters the orgasmic response.
A deficit of the male sexual hormone (testosterone) entails a reduction in sexual desire and atrophy of the cavernous nerves. Hyperthyroidism and diseases of the adrenal glands and hypophysis can also be a cause of ED.
It is calculated that between 20% and 30% of ED cases are due to the existence of psychological problems. A very important factor is so-called “performance anxiety”, which is produced not only by fear of failure but also by excess self-observation of the erectile response or by the obligation to produce optimum results and be over dependent on the partner’s satisfaction. All of this contributes to triggering sexual stress, changing an intimate, relaxed and pleasant experience into an obstacle course.
Antihypertensives and psychotropic drugs constitute the group of medications that most frequently cause ED. The most notable of the antihypertensives are diuretics of the thiazide group and beta-blockers. Among the psychotropic medications, the antipsychotics (phenothiazines and haloperidol), antidepressants of the serotonin uptake inhibitor group and the so-called tricyclic antidepressants cause ED and ejaculatory dysfunction. Drugs such as finasteride and dutasteride, used to treat benign hyperplasia of the prostate, as well as antiandrogens, can cause ED.