Erectile Dysfunction – Diagnosis, Symptoms, and Treatment

What is Erectile Dysfunction?

Erectile dysfunction (ED) is a medical condition characterized by the inability to initiate or maintain an erection.  It is commonly caused by psychological factors in young healthy men but may be due to underlying conditions such as obesity, hypogonadism, diabetes, peripheral vascular disease, or spinal problems in older adults.

Erectile dysfunction is an exceedingly common condition, especially in elderly males.  Individuals may have significant sexual desire but cannot sexually perform to their, or their partner’s, satisfaction – this may lead to reduced confidence and further difficulties maintaining an erection.  First-line medications are often helpful in alleviating symptoms but occasionally more invasive strategies are employed for patients with cases that do not respond to treatment.

What Causes Erectile Dysfunction?

Erectile dysfunction can be caused by a variety of conditions.  In young healthy men, it is typically related to psychological factors such as “performance anxiety.”  In older men with underlying medication problems, erectile dysfunction is often related to one or more of the following conditions:

• Obesity
• Smoking
• Hypogonadism – low testosterone levels
• Diabetes – resulting in nerve and blood vessel damage
• Peripheral vascular disease – reduced blood and oxygen supply
• Spinal disease – damaged nerves

Erectile dysfunction can also be caused by alcohol use or certain medications such as benzodiazepines (eg, Valium), antihypertensives (eg, beta-blockers, thiazide diuretics), and antidepressants (eg, SSRIs and tricyclic agents).

How Common is Erectile Dysfunction?

Erective dysfunction is the most common sexual health-related issue in men within the United States. It is estimated that 16% of men experience erectile dysfunction of some form in the United States. This condition is more common in older men, with 37% of sufferers in the 70-75 year age group. Younger men are affected as well with 8% of men between the age of 20-30 experiencing some degree of erectile dysfunction. 

Signs and Symptoms

Erectile dysfunction takes several forms with the unifying symptoms being difficulty initiating or maintaining an erection. The most common symptoms of erectile dysfunction are: 

• Inability to initiate an erection
• Impaired ability to maintain an erection
• Trouble ejaculating
• Absence of spontaneous morning erections

Patients with erectile dysfunction due to spinal disease have far more severe symptoms: muscle weakness, numbness, and tingling in the lower extremities are common.  In severe cases, patients will be paraplegic or quadriplegic.  Patients with poorly controlled diabetes may have a loss of sensation and poor circulation in the lower extremities.  They may also have polyuria (increased urination), polydipsia (excessive thirst), and polyphagia (excessive hunger).  Those with hypogonadism may have fatigue and decreased sexual desire in addition to the symptoms of erectile dysfunction.

Diagnosis

Erectile dysfunction generally does not need to be diagnosed as the patient will have a good idea that they are struggling with the condition. The key for physicians is determining the cause of the condition.  

The first step in the diagnosis of erectile dysfunction is determining if erections are occurring during sleep or in the morning upon awakening. If so, this is a sign that the patient's erectile dysfunction is psychological in nature. A more detailed discussion with your physician or a sexual therapist is generally then pursued to better determine the cause of erectile dysfunction in these patients. 

If you are older, have underlying medical conditions, or do not have morning erections your physician will often refer you for more detailed testing and perform a more detailed physical exam. 

Your doctor will usually order testosterone levels – these are typically obtained first thing in the morning.  Other commonly ordered blood tests include a CMP (comprehensive metabolic panel), CBC (complete blood cell count), and thyroid function (TSH, free T4).  They may also check your fasting cholesterol levels and screen you for diabetes.

On physical examination, your doctor will typically look for abnormalities in the appearance of the external genitalia, presence of pubic hair, and testicular size.  They will also typically examine the back and perform a neurologic evaluation for leg weakness, sensory loss, and hyperreflexia.  Your doctor may also examine for the cremasteric reflex in which they brush a Q-tip against the inner thigh and observe for the ascent of the testicle in the scrotum.  Your doctor may also perform a rectal examination to check for rectal tone, prostate size, and contour.

These exam maneuvers and tests help to exclude any issues with the nerves of the spine, the circulation, and the hormone levels in your body. 

Erectile Dysfunction Medication and Treatment

Erectile dysfunction is first treated by reversing any underlying conditions that may be contributing to symptoms.  This includes optimizing glucose control in diabetics, improving cholesterol levels, tobacco cessation, supplementing testosterone in patients that are deficient, and discontinuing alcohol and certain medications.

Patients may also benefit from a class of medications called phosphodiesterase-5 (PDE-5) inhibitors - these work by promoting engorgement of the penis via vasodilation.  The most commonly prescribed agents include:

• Viagra (sildenafil)
• Levitra (vardenafil)
• Cialis (tadalafil)

Patients that do not respond to the above measures may benefit from the self-injection of medications such as Muse (alprostadil) into the erectile tissue of the penis. Patients that continue to have symptoms despite these measures may be candidates for surgical implantation of a penile prosthesis.

References:

1. McVary KT. Clinical practice. Erectile dysfunction. N Engl J Med 2007; 357:2472. - https://www.ncbi.nlm.nih.gov/pubmed/18077811
2. Selvin E, Burnett AL, Platz EA. Prevalence and risk factors for erectile dysfunction in the US. Am J Med 2007; 120:151. - https://www.amjmed.com/article/S0002-9343(06)00689-9/fulltext