Risk of heterosexual HIV transmission attributable to sexually transmitted infections and non-specific genital inflammation in Zambian discordant couples, 1994-2012

• Type of Material: Article
• Authors: Kristin Wall, Emory University; William Kilembe, Emory University; Bellington Vwalika, Emory University; Lisa Haddad, Emory University; Eric Hunter, Emory University; Shabir A. Lakhi, Emory University; Roy Chavuma, Emory University; Naw Htee Khu, Emory University; Ilene Brill, Emory University; Cheswa Vwalika, Emory University; Lawrence Mwananyanda, Emory University; Elwyn Chomba, Emory University; Joseph Mulenga, Emory University; Amanda Tichacek, Emory University; Susan A Allen, Emory University
• Language: English
• Date: 2017-10-01
• Publisher: Oxford University Press (OUP): Policy B - Oxford Open Option D
• Publication Version: Final Published Version
• Copyright Statement: © The Author 2017. Published by Oxford University Press on behalf of the International Epidemiological Association.
• License: Creative Commons Attribution-NonCommercial 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1093/ije/dyx045
• Title of Journal or Parent Work: International Journal of Epidemiology
• ISSN: 0300-5771
• Volume: 46
• Issue: 5
• Start Page: 1593
• End Page: 1606
• Grant/Funding Information: The contents do not necessarily reflect the views of USAID or the United States Government.; This work was supported by: the National Institute of Child Health and Development (NICHD R01 HD40125); the National Institute of Mental Health (NIMH R01 66767); the AIDS International Training and Research Program Fogarty International Center (D43 TW001042); the Emory Center for AIDS Research (P30 AI050409); the National Institute of Allergy and Infectious Diseases (NIAID R01 AI51231; NIAID R01 AI040951; NIAID R01 AI023980; NIAID R01 AI64060; NIAID R37 AI51231); the US Centers for Disease Control and Prevention (5U2GPS000758); and the International AIDS Vaccine Initiative.; The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.; This study was made possible by the generous support of the American people through the United States Agency for International Development (USAID).
• Keywords: IMMUNODEFICIENCY-VIRUS TYPE-1; ACQUISITION; TANZANIA; CONTROLLED-TRIAL; DISEASES; HIV risk; ANTIRETROVIRAL THERAPY; TRACT INFECTIONS; genital ulceration and inflammation; discordant couples; Public, Environmental & Occupational Health; Science & Technology; longitudinal cohort; Zambia; Couples' voluntary HIV counselling and testing; AFRICAN WOMEN; INTRAVAGINAL PRACTICES; BACTERIAL VAGINOSIS; Life Sciences & Biomedicine
• Research Categories: Health Sciences, Medicine and Surgery; Health Sciences, Epidemiology; Health Sciences, Pathology

Abstract

Background: Studies have demonstrated the role of ulcerative and non-ulcerative sexually transmitted infections (STI) in HIV transmission/acquisition risk; less is understood about the role of non-specific inflammatory genital abnormalities. Methods: HIV-discordant heterosexual Zambian couples were enrolled into longitudinal follow-up (1994-2012). Multivariable models estimated the effect of genital ulcers and inflammation in both partners on time-to-HIV transmission within the couple. Population-attributable fractions (PAFs) were calculated. Results: A total of 207 linked infections in women occurred over 2756 couple-years (7.5/100 CY) and 171 in men over 3216 CY (5.3/100 CY). Incident HIV among women was associated with a woman's non-STI genital inflammation (adjusted hazard ratio (aHR) = 1.55; PAF = 8%), bilateral inguinal adenopathy (BIA; aHR = 2.33; PAF = 8%), genital ulceration (aHR = 2.08; PAF = 7%) and the man's STI genital inflammation (aHR = 3.33; PAF = 5%), BIA (aHR = 3.35; PAF = 33%) and genital ulceration (aHR = 1.49; PAF = 9%). Infection among men was associated with a man's BIA (aHR = 4.11; PAF = 22%) and genital ulceration (aHR = 3.44; PAF = 15%) as well as with the woman's non-STI genital inflammation (aHR = 1.92; PAF = 13%) and BIA (aHR = 2.76; PAF = 14%). In HIV-M+F- couples, the man being uncircumcised. with foreskin smegma. was associated with the woman's seroconversion (aHR = 3.16) relative to being circumcised. In F+M- couples, uncircumcised men with BIA had an increased hazard of seroconversion (aHR = 13.03 with smegma and 4.95 without) relative to being circumcised. Self-reporting of symptoms was low for ulcerative and non-ulcerative STIs. Conclusions: Our findings confirm the role of STIs and highlight the contribution of non-specific genital inflammation to both male-to-female and female-to-male HIV transmission/acquisition risk. Studies are needed to characterize pathogenesis of non-specific inflammation including inguinal adenopathy. A better understanding of genital practices could inform interventions.