Sexual interest and performance long have been associated with an adequate hormonal milieu, resulting in the indiscriminate administration of androgens to men with erectile dysfunction. Better understanding of penile physiology has shown that adequate sexual interest and erections can be maintained in the presence of diminished serum levels of testosterone. Nevertheless, hypogonadism affects sexual interest and erections adversely to variable degrees depending not only on the intensity of the deficiency but also on emotional and environmental factors and the degree of integrity of the neurovascular supply to the penis.

The most convincing evidence of a positive correlation between the incidence and severity of erectile dysfunction and aging has been provided by the Massachusetts Male Aging Study (MMAS).<sup>18 Feldman H.A., Goldstein I., Hartzichristou D.G. , e al. Impotence and its medical and psychosocial correlates: Results of the Massachusetts Male Aging Study J Urol 1994 ;  151 : 54-61

Cliccare qui per andare alla sezione Riferimenti</sup> Although the aging process in men is an interindividual variable, profound hormonal alterations and a decrease in sexual performance can occur. These two truisms (i.e., aging men sustain erectile dysfunction, and testosterone decreases with age) are not necessarily related and should not be construed to imply that erectile failure is exclusively a consequence of endocrine changes. The MMAS was unable to link the coexistence of erectile dysfunction and a decrease in the serum levels of sex hormones, with the notable exception of a direct correlation between erectile shortcomings and a serum deficit in dehydroepiandrosterone (DHEA) and its sulfated form (DHEAS). To interpret this finding, it must be remembered that, although hypotestosteronemia and aging show marked differences among men, the association of low DHEA and advancing age exhibits a more predictable, constant, and profound association. It is likely that the correlation between the progressive decrease in DHEA levels, diminished erectile capacity, and advancing age is purely coincidental. The role of DHEA and DHEAS in sexual performance and desire has not been investigated thoroughly and remains an interesting and fertile area of research. The role of androgens in sexual function in general and in erectile physiology in particular is of fundamental importance. It is estimated that 1 in 200 men have abnormally low levels of testosterone, and that most of them are candidates for androgen supplementation therapy.<sup>44 Replacing testosterone in men Drug Ther Bull 1999 ;  37 : 3-6

Cliccare qui per andare alla sezione Riferimenti</sup>