This is from the Journal of the American Medical Association via a Johns Hopkins Health Alert. These are free and very useful. You can subscribe @ johnshopkinshealthalerts.com.
Erectile Dysfunction Linked to Cardiovascular Disease and Diabetes
A study of nearly 4,000 men with an average age of 57 found that nearly half had experienced erectile dysfunction in the last month or were taking erectile dysfunction drugs. The development of erectile dysfunction was strongly related to the presence of cardiovascular disease (CVD) and diabetes, probably because of their negative effects on blood vessel function.
The relationship between erectile dysfunction and CVD or diabetes was most pronounced among men age 40–49. In these men, the probability of having erectile dysfunction was 31% in the absence of either medical condition but rose to 52% in men with CVD alone and to 73% in those who had CVD and diabetes. The relationship between erectile dysfunction and CVD or diabetes was apparent in all age groups but declined with age.