Racial/Ethnic Difference in CD4T Cell Count and Viral Load at Presentation for Medical Care and in Follow-up After HIV-1 Infection
September 19, 2002
Two-thirds of the individuals reported with AIDS in the United States in 2000 were from minority populations. Previous studies have shown racial differences in survival with AIDS, with black and Hispanic patients having significantly shorter survival times compared with white patients. Recent improvements in antiretroviral therapy have produced decreases in mortality rates in the United States, with less pronounced decreases for minority groups. Between 1998 and 1999, mortality rates for HIV-1 infected white adults fell by 15 percent, but only by 3 percent for black individuals. Delays of health care for HIV diagnosed patients are greater for Latino, and, to a lesser extent, black compared with white patients. Finally, observations from the authors' HIV clinic were of an increasingly large Latino population typically presenting later in the course of HIV disease. Once in care, the authors noted, Latino patients appeared to respond as well as other racial/ethnic groups.Adapted from:
In order to investigate the latter observations, the author undertook a retrospective analysis of antiretroviral-naïve HIV-1- infected patients presenting to the University of Nebraska Medical Center HIV Clinic between January 1996 and July 2001. The clinic database was queried for patient demographics, probable HIV transmission route, CD4 T cell counts, HIV-1-RNA measurements and the presence or absence of AIDS-defining opportunistic disease. Of the 372 participants, 26 percent were female, 56 percent were white, 25 percent were black and 16 percent were Hispanic. A total of 48 percent had been infected by homosexual exposure, 40 percent by heterosexual exposure, and 9 percent by intravenous drug use. Mean CD4 T cell count at first visit was 356 cells/mm3 (median 320, range 2-1438) and the mean HIV-1-RNA level was 101,140 copies/ml (median 27,207, range 25-943,573).
Significant differences were found in the distribution of "first visit" CD4 T cell counts. Hispanic patients had lower median counts (median 220 cells/mm3, n=50) when compared with black (median 318 cell/mm3, n=76) or white patients (median 372 cell/mm3, n=178. The distribution of HIV-1-RNA levels also differed significantly. The initial median viral load for white patients was 25,026 copies/ml and for black patients it was 21,489 copies/ml, whereas the median value for Hispanic patients was 64,121 copies/ml. The "first visit" CD4 T cell counts appeared to be higher and the initial RNA levels lower for women compared with men. Over time, the predicted mean change in CD4 T cell count from baseline increased significantly in increments of approximately 50 cells/mm3 for each 6-month period in all groups. None of the participant characteristic variables assessed was predictive of changes in the CD4 T cell count from baseline over time.
According to the authors, this "study indicates that patients from minority populations, especially Latino individuals, present with more advanced HIV disease when compared with white individuals, and that Latino individuals are significantly more likely to have a major opportunistic infection at presentation. However, once in care, increases in CD4 T cell counts and decreases in viral loads were no different for Latino than for white participants. Viral loads in follow-up appeared to be higher in black compared with white patients."
Citing various barriers to medical care for Hispanics influenced by geography, socioeconomic status and insurance, the authors noted that previous studies in military personnel have shown no association between viral load and race or ethnicity among adults for whom access to care and socioeconomic status were not confounding factors. The data suggest to the authors that "given a 'level playing field,' outcomes may not vary by race/ethnicity."
09.06.02; Vol. 16; No. 13: P. 1832-1834; Susan Swindells; Daniel G. Cobos; Nancy Lee; Elizabeth A. Lien; Ann P. Fitzgerald; Jennifer S. Pauls; James R. Anderson
This article was provided by CDC National Prevention Information Network. It is a part of the publication CDC HIV/Hepatitis/STD/TB Prevention News Update.