930 Differences in CD4 Counts in Ugandan and Zimbabwean Women Participating in the Hormonal Contraception and Risk for HIV-1 Acquisition Study R. A. Salata*1, P. G. A. Cornelisse2, T. Chipato3, F. Mmiro4, R. Mugerwa4, N. Padian5, B. Richardson2, C. S. Morrison6 1Case Western Reserve Univ, Cleveland, OH; 2Fred Hutchinson Cancer Res Ctr, SCHARP Statistical Ctr, Seattle, WA; 3Univ of Zimbabwe, Harare; 4Makerere Univ, Kampala, Uganda; 5Univ of California at San Fransisco; and 6Family Hlth Intl, RTP, NC
Background: A multi-country, prospective cohort study has enrolled women to evaluate the association of hormonal contraception (HC) on HIV acquisition. Following the primary endpoint of HIV seroconversion, women are asked to enroll into an HIV incident cohort to study the effect of HC and HIV subtypes on HIV genital shedding and disease progression.
Methods: Since March 2001, we have enrolled 118 women from Uganda (Ug) and Zimbabwe (Zim) into the incident cohort. Women are interviewed about hormonal exposure and sexual behaviors; undergo pelvic examinations, lymphocyte phenotyping, and screening for sexually transmitted infections every 3 months.
Results: As of October 2002, 145 cases (50 Ug, 95 Zim) of HIV seroconversion have been observed for an incidence rate of 2.5/100 women years. CD4 counts were available for 90 of these women (30 Ug, 60 Zim). At entry into the incident cohort, these women averaged 26 years of age, 66% were living with their primary partner, had a median of 1 sexual partner in the last 3 months and completed a median of 10 years of school. The prevalence of gonorrhea was 4.4%, chlamydia 6.7%, and syphilis 3.4%. At baseline, median CD4 counts were 658 in Ug and 544 cells/mm³ in Zim, (p < 0.001). Time from seroconversion to baseline CD4 count did not differ by site. Median CD4 counts at 3, 6, and 9 months post-seroconversion were 654, 530, 630 in Ug compared to 494, 482, 448 cells/mm³ in Zim (p < 0.001, 0.056, 0.015, resp.; n = 54). Twenty (20) women in Zim vs 2 in Ug developed CD4 counts < 300 cells/mm³ over a median period of follow-up of 8.3 months. At baseline, women with CD4 counts < 500 cells/mm³ had no distinguishing clinical, exam, or lab factors compared to women with > 500 cells/mm³.
Conclusions: At baseline and up to 9 months after HIV-1 seroconversion, Zim women demonstrate significantly lower CD4 counts than Ug women. Low baseline CD4 counts are not associated with unique clinical, PE and lab factors. Ongoing analysis will investigate whether observed differences and declines in CD4 cell counts are associated with HIV disease progression, HIV-1 subtypes, HIV RNA levels in genital secretions and HIV viral fitness.
