ANAL-SPHINCTER STRUCTURE AND FUNCTION IN HOMOSEXUAL MALES ENGAGING INANORECEPTIVE INTERCOURSE

Objectives: To evaluate the structure and function of the internal (IA S) and external (EAS) anal sphincters in anoreceptive homosexual men a nd to determine whether anoreceptive intercourse (ARI) is associated w ith a higher risk of incontinence in this population. Methods: We stud ied 14 anoreceptive homosexual males and 10 age-matched non-anorecepti ve heterosexual males in a controlled, prospective cohort study. Subje cts underwent evaluation of resting and maximum squeeze anal canal pre ssures (maximum squeeze pressure obtained over resting pressure) by st ation pull-through technique, using a manometric perfusion catheter fo llowed by endoanal ultrasonography to evaluate the structure of the IA S and EAS. Manometry also was performed in age-matched male controls. All subjects completed a questionnaire that assessed sexual practices and bowel habits, including fecal incontinence. Results: Resting press ures were significantly lower in subjects engaging in ARI (70.7 +/- 3. 2 mm Hg vs. 91.4 +/- 5.2 mm Hg; mean +/- SEM, p < 0.003), whereas ther e was no significant difference in the mean maximum squeeze pressures, compared with controls (177.1 +/- 14.1 mm Hg vs. 151.8 +/- 19.6 mm Hg ; mean +/- SEM, p = 0.32). No disruptions of the IAS or EAS were ident ified in either the anoreceptive or control group. Anoreceptive men te nded to have thinner anal sphincters than controls, but the difference was not statistically significant. Furthermore, there were no complai nts of fecal incontinence by the study subjects. Conclusions: Passive ARI is associated with decreased resting anal canal pressures, but tot al pressures are normal. There were no IAS or EAS defects, as well as no fecal incontinence, in our subjects. Better relaxation of the ARI s ubjects during anal canal manometry may explain the lower resting pres sures.