Association between male circumcision and incidence of syphilis in men and women: a prospective study in HIV-1 serodiscordant heterosexual African couples

Abstract

Background Male circumcision is a primary HIV-1 prevention intervention for men. It is uncertain whether male circumcision reduces the risk of syphilis among men and their female partners. Methods Using data from a prospective study among HIV-1 serodiscordant heterosexual couples from Kenya and Uganda, we assessed whether male circumcision was associated with incident syphilis in men and in their female partners. Multivariate Andersen-Gill survival methods were used, adjusted for age, sexual behavior, and plasma HIV-1 RNA levels of the HIV-1 infected partner. Findings 4716 HIV-1 serodiscordant couples (37·5% with an HIV-1 infected male) were followed for a median of 2·75 years. At enrollment, 1575 (53·5%) HIV-1 uninfected and 560 (32·4%) HIV-1 infected men were circumcised; an additional 69 (4·2%) HIV-1 infected and 132 (4·8%) HIV-1 uninfected men became circumcised during study follow up. 221 incident syphilis infections were observed: 46 among HIV-1 infected men (incidence 1·10 per 100 person-years), 76 among HIV-1 uninfected men (1·09 per 100 person-years), 54 among HIV-1 infected women (0·77 per 100 person-years) and 45 among HIV-1 uninfected women (1·11 per 100 person-years). Male circumcision was associated with a 42% reduction in incident syphilis in men (adjusted hazard ratio [aHR] 0.58 95% CI 0·37–0·91) including a 62% reduction among HIV-1 infected men (aHR 0·38, 95% CI 0·18–0·81) and a non-significant reduction in incident syphilis among HIV-1 uninfected men (aHR 0·64, 95% CI 0·36–1·11). Among women, circumcision of their male partners was associated with a 59% reduction in incident syphilis (aHR 0.41 95% CI 0.25–0.69), including a 75% reduction among HIV-1 uninfected women (aHR 0·25, 95% CI 0·08–0·76) and a 48% reduction among HIV-1 infected women (aHR 0·52, 95% CI 0·27–0·97). Interpretation In this large prospective cohort study among HIV-1 serodiscordant couples, male circumcision was associated with decreased risk of incident syphilis in men and women. If confirmed, these results suggest that medical male circumcision could substantially reduce incidence of syphilis and its sequelae. Funding Bill & Melinda Gates Foundation (grant OPP47674) and the Eunice Kennedy Shriver National Institute of Child Health and Human Development (K99HD076679).

“The Cango Lyec Project - Healing the Elephant”: HIV related vulnerabilities of post-conflict affected populations aged 13–49 years living in three Mid-Northern Uganda districts

“…Further, a study of young conflict-affected people aged 15–29 residing in transit camps in Northern Uganda observed that ever having had an STI was associated with a four-fold increase in HIV risk among young women, but was not significantly associated with HIV risk among young men [55]. Active syphilis and other GUD in conjunction with low prevalence of male circumcision is worrisome and may be a warning sign for a rise in new HIV infections in the aftermath of war [56]. These findings highlight the importance of post-conflict HIV prevention interventions that support access to STI diagnosis and treatment.…”

Critical evaluation of arguments opposing male circumcision: A systematic review

“…As documented in a critical review, RCTs and other studies have found MC affords protection against Trichomonas vaginalis (50%), Mycoplasma genitalium (40%), Treponema pallidum (syphilis) (33‐50%), chancroid (50%), and genital ulcer disease (50%) . Genital ulcers in uncircumcised men contain a higher prevalence of anaerobic bacteria.…”

“…298 A large prospective cohort study of 2946 HIV-negative couples found syphilis was 75% lower in the female partners of circumcised men. 284 A prospective study in Kenya by the same authors found that those with circumcised male partners had a 58% lower risk of incident Trichomonas vaginalis compared to women with uncircumcised partner. 302 A recent systematic review of MC and STIs in women identified 9…”

“…For other STIs, a RCT found that genital ulcer disease risk was 22% lower in women with circumcised male partners, bacterial vaginosis was 40% lower, severe bacterial vaginosis was 61% lower, and Trichomonas vaginalis was 48% lower, but there was no difference in dysuria or vaginal discharge . A large prospective cohort study of 2946 HIV‐negative couples found syphilis was 75% lower in the female partners of circumcised men . A prospective study in Kenya by the same authors found that those with circumcised male partners had a 58% lower risk of incident Trichomonas vaginalis compared to women with uncircumcised partner …”

“…Morris et al, 269 Castellsagué et al, 270,300 Homfray et al, 271 Backes et al, 262 Hernandez et al, 273 Lu et al, 274 Albero et al, 275 Tobian et al, 277,278 Sobngwi-Tambekou et al, 279,282 Mehta et al, 280 Pintye et al, 284,302 Otieno-Nyunya et al, 285 Nasio et al, 286 Poynten et al, 304 Templeton et al 305…”