ANXIETY-INDUCED FAILURE IN ERECTILE RESPONSE TO INTRACORPOREAL PROSTAGLANDIN-E(1) IN NONORGANIC MALE IMPOTENCE - A NEW DIAGNOSTIC-APPROACH

Intracavernous injection (ICI) of prostaglandin-E(1) (PGE(1)) is used widely as the first diagnostic test in the study of erectile dysfuncti on. However, a lack of full erection after a maximal dose is frequent. As well as vascular incompetence, this may be due to stress-induced c hanges, related to the ICI procedure. Tile aim of this study was to in vestigate the influence of emotional disturbances on erectile response to ICI in impotent patients. Initially, 24 young men with non-organic impotence (age 34.6 +/- 1.5 years; mean +/- SEM) were selected and ra ndomized single-blind to pharmacoerection with PGE(1) alone (20 mu g/m L) or a mixture (cocktail) containing 20 mu g PGE(1) plus an alpha-adr energic receptor blocker, phentolamine (Phe, 0.5 mg/mL). Additional st udies were also performed double-blind on 10 men with non-organic impo tence (age 37.6 +/- 1.2 years) utilizing higher PGE(1) dosages for ICI (25 mu g/mL alone or in combination with Phe, 0.5 mg/mL). After a 7-d ay interval, all subjects were crossed-over to receive the alternative treatment. The presence of emotional disturbances was assessed in all patients by the administration of rapid tests (Stai-X1 and Stai-X1r f or state-anxiety before and after ICI, respectively; Stai-X2 for trait -anxiety; Zung-test for depression) at the first and at the remaining (Stai-X1 and Stai-X1r) ICI sessions. ICI with 20 and 25 mu g/mL PGE(1) led to a comparable percentage of patients who reported a valid-for-i ntromission (VFI) erection (63 and 60%, respectively). In contrast, us e of the cocktails significantly increased the percentage of subjects with a VFI (87 and 90% of the total number of patients tested, respect ively; p < 0.05). Moreover, a strong inverse correlation between state -anxiety scores (Stai-X1) and the erectile response to ICI with 20 and 25 mu g PGE(1) was found (r = -0.69, p < 0.001); such a correlation w as not present in patients who underwent ICI with the cocktails. Two c ases of prolonged erection occurred (one after 20 mu g PGE(1) and the other after 20 mu g PGE(1) plus Phe) which were reversed promptly by t he intracavernous injection of metharaminol. It is concluded that the lack of a full, erectile response after ICI with PGE(1) can be related to the presence of a high 'State-anxiety' in the patients. In such pa tients, a VFI erectile response can be induced by the administration o f a cocktail test-dose.