1. A generation has passed since the vascular origin of erectile dysfunction was revealed to a conference of astounded urologists with a live demonstration of papaverine injection. But the real breakthrough in erectile dysfunction treatment came in 1998, when sildenafil (Viagra), first of the PDE5 inhibitors, hit the market. For the first time, there was a practical, effective treatment that helped a majority of patients. But its effectiveness has forced us to look closer at the vascular causes of ED, with some disquieting results.

2. ED is a predictor of coronary artery disease and diabetes. In fact, ED is the presenting symptom in about 20% of new male diabetes cases. About 60% of male patients with hypertension experience ED. In a population with no known cardiovascular disease, ED is as good a predictor of cardiovascular risk as 1^st-degree family history or current smoking. ED typically occurs about 3 years before first coronary symptoms and 5 years before the first event. Sadly, men with ED wait an average of 3 years before sharing the problem with their doctor.

3. Always check ED patients for diabetes. Always ask male diabetic patients about ED. In diabetes, it’s a better predictor of a CV event than either HbA_1c or microalbuminuria.

4. Always check testosterone levels in all patients. These are twice as likely to be low in a diabetic patient. Low testosterone is the number one cause of treatment failure on PDE5 inhibitors. A patient with low testosterone should have that treated first. It can take six months, but may well resolve the problem on its own. If not, it will improve effectiveness of PDE5 inhibitor therapy.

5. Consider medication history. Drugs associated with ED include SSRI antidepressants, antipsychotics, thiazide diuretics and most ß-blockers.

6. Hypertension certainly needs to be treated, however. ACE inhibitors appear to have no net effect on ED, but ARBs can help and will actually resolve some mild cases of ED (typically bringing a 5-6 point improvement on the Sexual Health Inventory for Men).

7. Dyslipidemia also needs to be addressed, and statins, like ARBs, can sometimes resolve ED on their own, after about six months’ therapy.

8. ED patients bear twice the normal burden of depression. But it’s often best to treat the ED first. Instead of prescribing an SSRI that will impair erection, prescribe a PDE5, and testosterone if it’s low. Both restored sexual function and normal testosterone levels are likely to do wonders for that depression.

9. PDE5 drugs are safe and well-tolerated, and bring overall vascular benefits — tadalafil is nowadays approved in the U.S. for pulmonary hypertension. Start patients at full dose — you can titrate down later — and don’t skimp on the quantities. Forcing patients to come back constantly for embarrassing repeat prescriptions is a short-cut to treatment failure.

10. As for the pumps and injection therapies that were so prevalent before Viagra came along, they still have a place. PDE5 inhibitors work best when ED is vascular in origin, least well with neurologic and surgical causes. They are 75% effective in the general ED population, but only 55% in type 2 diabetes, and 30% following radical prostatectomy. Half of those who fail to benefit from PDE5 therapy will benefit from intracavernosal injection — but half will abandon it within 12 months. Vacuum therapy generally produces some erection, but it’s rarely very rigid, it feels cold, and the ring interferes with ejaculation. So it’s wise to try PDE5 inhibitors first.