Other hormone levels: Measurement of other hormones beside testosterone (luteinizing hormone [LH], prolactin level, and cortisol level) may provide clues to other underlying causes of testosterone deficiency and erectile problems, such as pituitary disease or adrenal gland abnormalities. Doctors may check thyroid levels in some individuals as both hypothyroidism (low thyroid function) and hyperthyroidism (overactive thyroid function) can contribute to erectile dysfunction.
It is normal for a man to have five to six erections during sleep, especially during rapid eye movement (REM). Their absence may indicate a problem with nerve function or blood supply in the penis. There are two methods for measuring changes in penile rigidity and circumference during nocturnal erection: snap gauge and strain gauge. A significant proportion of men who have no sexual dysfunction nonetheless do not have regular nocturnal erections.
The association of CVD and ED was noted in 1997 as one analysed the results of the MMAS. In this landmark study, 1709 men aged 40–70 years were enrolled between 1987 and 1989. A follow-up some 10 years later revealed a striking relationship between ED and CVD. In this study, it became clear that the risk factors for ED were very similar to those of CVD, such as diabetes mellitus, smoking and dyslipidaemia.18
In a prospective study from the Prostate Cancer Prevention Trial database, Thompson et al reported that men presenting with ED had a significantly higher chance of developing a cardiovascular event over a 7-year follow-up period.  The hazard ratio was 1.45, which is in the range of risk associated with current smoking or a family history of MI.
Several studies accessed the prevalence of ED. The Massachusetts Male Aging Study reported a prevalence of 52%.2 The study demonstrated that ED is increasingly prevalent with age: approximately 40% of men are affected at age 40 and nearly 70% of men are affected at age 70. The prevalence of complete ED increased from 5% at age 40 to 15% at age 70.2 Age was the variable most strongly associated with ED.
Many factors can contribute to sexual dysfunction in older men, including physical and psychological conditions, comorbidities and the medications used to treat them. Aspects of an ageing man’s lifestyle and behaviour and androgen deficiency, most often decreasing testosterone levels, may affect sexual function as well. A study of men between the ages of 30 and 79 years showed that 24% had testosterone levels below 300 ng/dL and 5.6% had symptomatic androgen deficiency.2
ED is defined as the inability to achieve a full erection or the inability to maintain an erection adequate for sexual intimacy. Other types of sexual dysfunction such as premature ejaculation and low libido may occur; however, the most common and disruptive problem in men is ED. Although most men will experience periodic episodes of ED, these episodes tend to become more frequent with advancing age.
In some cases, nocturnal penile tumescence testing is performed to find out whether the man has erections while asleep. Healthy men usually have about four or five erections throughout the night. The man applies a device to the penis called a Rigiscan before going to bed at night, and the device can determine whether he has had erections. (If a man is able to have normal erections at night, this suggests a psychological cause for his impotence.)
Medication therapy is extremely effective in augmenting the quality of man’s erection such that he is able to have satisfactory intercourse. Indeed medications referred to as phospho-diesterase inhibitors such as Cialis, Viagra, Levitra and Stendra work in 65% of men suffering from erectile dysfunction. Cialis is currently the preferred drug since it is the only one that may be taking on a full stomach and lasts for 36 hours. This favors a more romantic and natural sexual interaction. Planning kills the mood!
Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
The prostaglandin E1 is contained in a small suppository located at the tip of an applicator. You should urinate first as this lubricates the urethra and makes it easier to insert the applicator into the tip of the urethra (urethral meatus, the opening at the tip of the penis that urine passes through). A patient can release the suppository into urethra by gently wiggling the applicator and pressing the button at the end. Rubbing the penis allows the suppository to dissolve, and the prostaglandin is absorbed through the tissue of the urethra into the penis. It takes 15 to 30 minutes for this occur. Once into the penis, the prostaglandin causes increased blood flow into the penis. The prostaglandin can be present in the ejaculate, and thus doctors recommend that men use a condom when having intercourse with a pregnant partner. Men may need to use a condom if vaginal irritation occurs in female partner.
A common and important cause of ED is vasculogenic. Many men with ED have comorbid conditions such as hyperlipidemia, hypercholesterolemia, tobacco abuse, diabetes mellitus, or coronary artery disease (CAD).  The Princeton III Consensus recommends screening men who present with ED for cardiovascular risk factors; ED may be the earliest presentation of atherosclerosis and vascular disease. 
Other medical therapies under evaluation include ROCK inhibitors and soluble guanyl cyclase activators. Melanocortin receptor agonists are a new set of medications being developed in the field of erectile dysfunction. Their action is on the nervous system rather than the vascular system. PT-141 is a nasal preparation that appears to be effective alone or in combination with PDE5 inhibitors. The main side effects include flushing and nausea. These drugs are currently not approved for commercial use.
For many of the 30 million Americans affected by erectile dysfunction, Viagra, Levitra, and Cialis are the first line of ED treatment — and they’re successful for about 80 percent of men. These drugs, called phosphodiesterase-5 inhibitors, are approved by the U.S. Food and Drug Administration (FDA) and work by increasing blood flow to an erection. Common side effects include nasal congestion and headache. Note: If you take nitroglycerin pills for heart disease, you won’t be able to take ED pills, as they can cause a dangerous drop in blood pressure.
Alprostadil should not be used in men at higher risk for priapism (erection lasting longer than six hours) including men with sickle cell anemia, thrombocytopenia (low platelet count), polycythemia (increased red blood cell count), multiple myeloma (a cancer of the white blood cells), and is contraindicated in men prone to venous thrombosis (blood clots in the veins) or hyperviscosity syndrome who are at increased risk for priapism.
What happens is that the blood vessels of the penis are rather small, and a small amount of plaque in the penile arteries is going to result in erectile dysfunction. You need more plaque before the person’s actually symptomatic from a heart problem, but they’re linked. And so when anybody, any man has an erectile issue, it’s incumbent upon the physician to make certain that their cardiac status is healthy.
Acupuncture may help treat psychological ED, though studies are limited and inconclusive. You’ll likely need several appointments before you begin to notice any improvements. When choosing an acupuncturist, look for a certified practitioner who uses disposable needles and follows U.S. Food and Drug Administration guidelines for needle disposal and sterilization.
Associated morbidity may include various other male sexual dysfunctions, such as premature (early) ejaculation and male hypoactive sexual desire disorder. The NHSLS found that 28.5% of men aged 18-59 years reported premature ejaculation, and 15.8% lacked sexual interest during the past year. An additional 17% reported anxiety about sexual performance, and 8.1% had a lack of pleasure in sex. 
However, in contrast, a recent systematic review of published studies, the authors concluded that overall, the addition of testosterone to PDE-5 inhibitors might benefit patients with ED associated with testosterone levels of less than 300 ng/dL (10.4 nmol/L) who failed monotherapy.  A limitation of existing studies are their heterogeneous nature and methodological drawbacks.
Vacuum devices for ED, also called pumps, offer an alternative to medication. The penis is placed inside a cylinder. A pump draws air out of the cylinder, creating a partial vacuum around the penis. This causes it to fill with blood, leading to an erection. An elastic band worn around the base of the penis maintains the erection during intercourse.