Common Causes of Erectile Dysfunction: The Role of Chronic Diseases and Medications
Among the causes of erectile dysfunction (ED), medications account for up to 25% of all cases (1). Since both various diseases and the drugs used to treat them can impair erectile function, it is important to consider both the underlying medical conditions and their pharmacological management.
It is worth noting that erectile dysfunction in younger men is more often caused by psychological factors, whereas in older men it is usually of organic origin, most commonly due to atherosclerotic narrowing of the penile arteries.
Cardiovascular diseases: arterial hypertension
An erection depends on adequate dilation of the penile blood vessels, making both elevated and reduced blood pressure important factors affecting erectile function.
The prevalence of ED in patients with arterial hypertension depends on the severity and duration of the disease, as well as accompanying conditions. Studies show that men with arterial hypertension experience erectile dysfunction approximately twice as often as men of the same age with normal blood pressure. According to other researchers, ED affects 44% or more of patients with arterial hypertension (2, 3).
[Interestingly, arterial hypertension often remains asymptomatic for many years because the body gradually adapts to elevated blood pressure. However, untreated hypertension can eventually lead to stroke, myocardial infarction, and other serious complications. For this reason, it is often referred to as the "silent killer."]
Hypertension is treated with various classes of medications, which differ in their effects on erectile function. Diuretics and beta-blockers (except vasodilating beta-blockers) are considered the most likely to worsen erectile function. Calcium channel blockers and angiotensin-converting enzyme (ACE) inhibitors are generally regarded as neutral, whereas angiotensin II receptor blockers (ARBs) and some vasodilating beta-blockers may have a beneficial effect on erectile function (4).
Heart failure
Heart failure develops when the heart's pumping ability becomes impaired and is more common in older adults. Erectile dysfunction occurs in approximately three-quarters of these patients (5). Potent diuretics (particularly aldosterone antagonists) and beta-blockers (except vasodilating beta-blockers) may negatively affect erectile function. ACE inhibitors are generally considered neutral, while ARBs and certain vasodilating beta-blockers appear to have the most favorable effect.
Coronary artery disease
The penile arteries are similar in size and structure to the coronary arteries. Consequently, atherosclerosis of the penile arteries and its consequences—erectile dysfunction—often develop before clinical manifestations such as myocardial infarction. Polish researchers found that more than half of men experienced erectile dysfunction before suffering a heart attack (6).
Among medications used to treat coronary artery disease, beta-blockers commonly impair erectile function, whereas calcium channel blockers and ACE inhibitors are generally considered neutral, and ARBs appear to be the most favorable. Other medications, including antiplatelet agents, anticoagulants, and lipid-lowering drugs, generally do not have a significant adverse effect on erectile function. It is important to remember that nitrate preparations are contraindicated in patients taking phosphodiesterase type 5 (PDE5) inhibitors because of the risk of severe hypotension.
Diabetes and medications used to treat it
Diabetes mellitus is characterized by widespread and rapidly progressing atherosclerosis, which also affects the penile arteries. Up to 55% of patients with diabetes develop erectile dysfunction, and ED typically occurs 10–15 years earlier than in men without diabetes (7). In addition to atherosclerosis, diabetic peripheral neuropathy also contributes to erectile dysfunction.
Both hypoglycemia and hyperglycemia can negatively affect erectile function. Therefore, maintaining good glycemic control, together with appropriate blood pressure management, may help reduce diabetes-related vascular complications.
Prostate diseases and medications used to treat them
Benign prostatic hyperplasia (BPH) develops as a result of enlargement of the prostate gland due to alterations in testosterone metabolism. It is a very common condition. Approximately 14% of men are affected by the age of 40, more than 50% by the age of 60, and up to 90% of men older than 85 years. As the prostate enlarges, it compresses the urethra, causing lower urinary tract symptoms. Frequent nighttime urination disrupts sleep and may also impair sexual function.
The main medications used to treat BPH are alpha-adrenergic blockers. These drugs generally do not impair erectile function but commonly cause ejaculatory disorders. In contrast, 5-alpha-reductase inhibitors, which reduce prostate volume, frequently contribute to erectile dysfunction because they interfere with testosterone metabolism (8). Treatments for prostate cancer, including medications and other therapeutic approaches, may also significantly impair erectile function.
Depression and antidepressants
Patients with depression frequently experience sexual dysfunction, including reduced libido and erectile dysfunction. Conversely, erectile dysfunction and ejaculatory disorders themselves may contribute to the development of depression. For example, severe erectile dysfunction increases the risk of depression up to sixfold.
Various antidepressants are used to treat depression. According to published studies, 40–60% of patients taking antidepressants experience erectile dysfunction (9). Sexual dysfunction is therefore a common adverse effect of antidepressant therapy. The underlying mechanism is thought to involve the effects of these medications on neurotransmitters such as serotonin and norepinephrine, which play important roles in the central regulation of sexual function. The degree of sexual dysfunction varies between different classes of antidepressants.
Other psychiatric disorders (schizophrenia, bipolar disorder, etc.)
Erectile dysfunction affects approximately 45–80% of patients with schizophrenia (10). Antipsychotic medications, as well as the psychiatric disorders themselves, negatively affect erectile function and other aspects of sexual performance. Their mechanism of action primarily involves interference with dopamine and other neurotransmitter systems.
Many other medications may also contribute to erectile dysfunction, including opioid analgesics, central nervous system depressants (tranquilizers), anticancer agents, certain antifungal drugs, and various hormonal preparations (11).
In summary, many diseases and the medications used to treat them may contribute to erectile dysfunction. However, this does not mean that these conditions should remain untreated. On the contrary, appropriate treatment is essential, while careful selection of medications may help minimize adverse effects on sexual function. Likewise, erectile dysfunction itself should also be treated, as successful management often improves the overall quality of life of patients living with these chronic diseases.
