Erectile dysfunction ED is a type of sexual dysfunction (Impotence), is a common problem among men and is characterized by the consistent inability to sustain an erection sufficient for sexual intercourse or the inability to achieve ejaculation, or both. It is a male sexual dysfunction and expressed in the inability to have an erection sufficient for sexual intercourse.Common-Male-Sex-Problems-730x410

Functional erectile difficulties are the result of inadequate blood inflow, disrupted neurological signals, or venous leak. This pathophysiology stems from either poor sexual interest or central arousal to trigger the spinal cord erectile reflexes, medication affecting sexual abilities, or from a generalized medical condition.

Endo­thelial and metabolic risk factors seen in cardiovascular disease, including lack of exercise, obesity, smoking, hypercholesterolemia, diabetes, and the metabolic syndrome, can also contribute to ED. The risk of ED, particularly in a younger man, may be re­duced by modifying these risk factors (e.g., increasing exercise and losing weight)

The erectile process depends on the nitric oxide-cyclic guanosine mono­phosphate (NO-cGMP) pathway. There are two main sources of nitric oxide: from penile nerve endings (nNO) and from healthy endothelial lining (eNO). Hypertension, hyper­lipidemia, smoking, and other factors can damage the source of eNO, and men with these conditions are therefore at higher risk for ED.

These patients will also require higher doses of the phosphodiesterase type 5 (PDE5) inhibitors such as Sildenafil (Viagra), Vardenafil (Levitra, Staxyn), and Tadalafil (Cialis), since PDE5 inhibi­tors are reliant on the NO-cGMP pathway triggered by sexual arousal.

Men at high risk for neurological ED include those with neurological conditions such as MS, Parkinson disease, and traumatic brain injury, or those who have undergone pelvic, prostate, bladder, or abdominal surgery that interferes with peripheral nerve innervation, reducing nNO. Ra­di­cal prostatectomy in any form (open, laparoscopic, or robotic) often results in ED despite good nerve-sparing operative technique, because of both nerve and hemodynamic damage.

Poor erectile function can also be caused by incompetence of the veno-occlusive mechanism through aging, Peyronies disease, low testosterone, and by surgical or congenital issues causing a deeper venous leak. Lower urinary tract symptoms (LUTS) are an independent risk factor for ED and may share similar pathophysiolgical mechanisms.

Men with diabetes have ED secondary to neuropathy, vascular factors (both large vessel and small vessel disease), and functional and structural abnormalities within the corpus cavernosum itself. Furthermore, the quality of their erections is affected by glycemic control. Hy­pothyroidism and hypogonadism also affect erections.