Whatever the cause of their patients ED, they are not alone. Millions of men are experiencing common symptoms and emotions while searching for an Erectile Dysfunction treatment that works. A number of different factors can cause Erectile Dysfunction. The condition is often caused by an underlying medical condition, physical or psychological cause. About 80% of chronic ED cases are caused by diabetes, vascular disease, hypertension, penile curvature, prostate cancer or spinal cord injuries.