What causes erectile dysfunction?

Although erectile dysfunction can have psychological causes, in most cases the cause is physical. Some of the common causes of erectile dysfunction include high blood pressure, high cholesterol, diabetes and even heart disease.
Other common risk factors associated with erectile dysfunction  include a sedentary lifestyle, obesity, sleep apnea and smoking.
Some medications can cause erectile dysfunction as well, and it is also common in patients who have undergone prostate surgery.
Erectile dysfunction and cardiovascular (CV) disease share many causes. As a consequence, erectile dysfunction severity correlates with the degree of CV disease and the persistence of erectile dysfunction highly correlates with a subsequent cardiac event.

Among the psychological causes, the most common ones are:

• Personal issues (i.e. stress, anxiety, depression)
• Relationship problems
• Psychosexual factors (i.e. sex seen as a taboo subject, past negative experiences)
• Sexual development (i.e. sexual orientation, sexual development during adolescence)

McVary KT. Sexual Dysfunction, in Harrison’s Principles of Internal Medicine, Longo DL, et al., Editors. 2012, McGraw Hill: New York. p.374-379.
Kaminetsky J. Epidemiology and pathophysiology of male sexual dysfunction. Int J Impot Res 2008;20(Suppl1):S3-10.