AEGiS-14IAC: Differences between the Mwanza, Rakai and Masaka populations: a reanalysis of trial data.

14th International AIDS Conference

Barcelona, Spain - July 7-12, 2002

Differences between the Mwanza, Rakai and Masaka populations: a reanalysis of trial data.

Int Conf AIDS 2002 Jul 7-12; 14:(abstract no. MoOrD1085)

Orroth KK, Korenromp EL, White RG, Gavyole A, Sewankambo NK, Wawer MJ, Whitworth JA, Grosskurth H, Habbema JD, Hayes RJ
London School of Hygiene and Tropical Medicine, London, United Kingdom

Title Differences between the Mwanza, Rakai and Masaka populations: a reanalysis of trial data

BACKGROUND: Community randomised trials in Mwanza, Rakai and Masaka have reported differing impacts of STD treatment on HIV incidence. Data on sexual behaviour and STD prevalences were compared between the three trials to determine to what extent the results might be explained by these population differences.

METHODS: Baseline survey data from the three trials were compared after age-standardization. STD rates were also adjusted for the sensitivities and specificities of the different diagnostic techniques used.

RESULTS: Fertility, mortality, immigration, population composition and marriage patterns were similar across populations, apart from effects of AIDS on mortality (including widowhood) and fertility. Higher risk behaviour, including younger age of sexual debut, higher numbers of recent partners and lower frequency of condom use, was apparent in Mwanza compared to Masaka and Rakai. Active syphilis, gonorrhoea, chlamydia and trichomoniasis were all more prevalent in Mwanza, except for chlamydia in males. There was little difference in HSV2 seroprevalence between sites (table). [table: see text] Age patterns in the prevalence of HSV2, short-duration STD and current risk behaviours were similar across sites, but among older participants (age>40) TPHA and low-titre RPR were more prevalent in Rakai and Masaka than Mwanza.

CONCLUSIONS: The main differences between trial populations include higher risk behaviour and consequently higher rates of curable STD in Mwanza compared to Rakai and Masaka. These differences may be the result of recent reductions in risk behaviour in Uganda and explain in part the seemingly contrasting results of these trials.

Keywords: AEGIS, Prevalence, Incidence, HIV Infections, Sex Behavior, Risk-Taking, Gonorrhea, Chlamydia Infections, Acquired Immunodeficiency Syndrome, Uganda, Population, Syphilis, Widowhood, Seroepidemiologic Studies, Human, Male

020707
MoOrD1085