Comparison of sexually transmitted disease prevalence by reported level of condom use among patients attending an urban sexually transmitted disease clinic

Background: There is controversy as to the protective effect of condoms in preventing various sexually transmitted diseases (STDs). Goal. The goal of this study was to assess the association of various levels of condom use with a variety of STD. Study Design: We conducted a cross-sectional study of female and heterosexual male visits to an urban STD clinic between 1990 and 2001. Methods: Prevalence rates were calculated for gonorrhea, chlamydia, trichomonas, recent-onset genital warts, first-episode herpes, and molluscum contagiosum by reported level of condom use over the past 4 months, with adjusted odds ratios (AOR) calculated by logistic regression. Results: Among 126,220 patient visits (39% women and 61% men), condom use over the past 4 months was reported by 54%, with 38% reporting inconsistent use and 16% consistent use. Condom users reported greater sexual risk in the past 4 months than nonusers (ie, new sex partners: 63% vs. 41%, P < 0.001; multiple sex partners: 60% vs. 36%, P < 0.001). When all condom users were compared with nonusers, there was limited evidence of protection against specific STD. However, when the analysis was restricted to condom users infection rates were significantly lower in consistent than inconsistent users for both men and women for gonorrhea (AOR, 0.87 and 0.71, respectfully) and chiamydia (AOR, 0.66 and 0.74, respectfully), for trichomonas in women (AOR, 0.87), and for genital herpes in men (AOR, 0.73). Conclusions: Comparisons of STD between condom users and nonusers are confounded by greater sexual risk in users. Comparing consistent with inconsistent users reduces this confounding, revealing protection for both men and women for nonviral STD and for genital herpes for men.