Erectile disorder (ED) is defined as the persistent inability to obtain or maintain an erec­tion sufficient for satisfactory sexual performance (Fink et al., 2002). It is estimated that close to 30 million men in the United States experience ED (Lue, 2000). The preva­lence of ED increases with age—12% of men younger than 59 experience ED, whereas 22% of men aged 60 to 69, and 30% of men over the age of 69 experience ED (Bacon et al., 2003).

We know that normal erectile function involves neurological, endocrine, vascular, and muscular factors. Psychological factors including fear of failure and performance anxiety may also affect erectile functioning. Anxiety has been found to have a cyclical effect on erectile functioning: if a man experiences a problem getting an erection one night, the next time he tries to have intercourse he remembers the failure and becomes anxious. This anxiety, in turn, interferes with his ability to have an erection.

Подпись:Problems in any of these areas can lead to ED, although the majority of cases are caused by a combination of factors (Fink et al., 2002). Unfortunately, when a physician identifies a physical problem (such as hypertension), he or she might not continue to ex-


"In the process of becoming aroused, all of a sudden it would be over. And I didn’t understand that at all."—Erectile Dysfunction: Clark

Sexuality* «Now

Подпись: nocturnal penile tumescence (NPT) test A study done to evaluate erections during sleep that helps clarify the causes of erectile dysfunction. Подпись:Male Erectile DisorderПодпись:Подпись:Подпись:plore the psychological factors. Or if a psychological problem is found first (such as a re­cent divorce), the physician might not perform a medical evaluation. Overall, EDs in younger men (20 to 35 years old) are more likely to be psychologically based, whereas EDs in older men (60 and older) are more likely to be due to physical factors (Lue, 2000).

To diagnose the causes of erectile disorder, sex therapists can use tests such as the nocturnal penile tumescence (NPT) test. Men normally experience two or three erections a night during stages of rapid eye movement (REM) sleep. If these erections do not occur, it is a good indication that there is a physiological problem; if they do occur, erectile problems are more likely to have psychological causes. The NPT re­quires a man to spend at least three nights in a sleep laboratory hooked up to several machines, but newer devices allow him to monitor his sleep erections in the privacy of his own home. RigiScan, a portable diagnostic monitor, measures both rigidity and tumescence at the base and tip of the penis. Stamp tests and other at-home devices are also used. A stamp test uses perforated bands resembling postage stamps, which are placed on the base of the penis prior to retiring for the night. In the morning, if the perforations have ripped, this indicates that the man had normal physiological func­tioning while sleeping.