Race does not affect virological, immunological, or clinical response to antiretroviral therapy amongst women who continue taking HIV therapy after initiating highly active antiretroviral therapy (HAART), according to a study conducted in the United States and published in the August 15th edition of the Journal of Acquired Immune Deficiency Syndromes. The investigators, from the Women’s Interagency HIV Study (WIHS), found however, that discontinuing HAART and to a lesser extent, depression, were both associated with a poorer response to antiretroviral therapy.
Most of the information about the effectiveness and safety of anti-HIV treatment was obtained from studies involving men. There are concerns that drug metabolism may be affected by race and that this might have an unfavourable impact on the success of anti-HIV treatment. In addition, studies have suggested that behavioural characteristics also differ between racial groups and this could also impact on the effectiveness of HAART.
On the surface, mortality figures in the US seem to support the hypothesis that the effectiveness of HAART differs by race. Since effective anti-HIV drugs became routinely available, HIV-related mortality amongst white men in the US has fallen by 85% compared to only 50% in black women and 65% in black men.
Investigators from the WIHS study therefore hypothesised that African American women, who are more likely to have a natural polymorphism that can affect the success of HAART, would have a poorer response to HAART even after adjusting for social factors and issues such as HAART continuation and adherence.
To test this hypothesis, data from 961 women who started HAART between 1995 and 2003 were analysed. A total of 60% of these women were African American, 20% were white and 20% were Hispanic.
There were significant socio-demographic differences between the racial groups. African American women were older, less well educated, started HAART later, and were more likely to report pre-HAART use of alcohol, cigarettes and illicit drugs than white or Hispanic women. In addition, Hispanic women were more likely than white or African American women to be on a low income, be depressed and to report not using antiretroviral therapy after starting treatment with it.
After almost eight years of follow-up, the investigators found that 70% of African American women were still alive, compared to 77% of Hispanic women and 80% of white women.
In their initial statistical analysis, the researchers established that white women were significantly more likely than African American women to get their viral load below 80 copies/ml after starting HAART; experience an increase of at least 100 cells/mm3 after initiating HIV treatment; and were less likely to experience a rebound in their viral load or die of any cause.
However, the investigators repeated their statistical analysis and included continued use of antiretroviral therapy after initiation of HAART as a factor. They found that “there were no significant differences by race in virologic, immunologic, or clinical response to HAART.”
They then restricted their analysis to the 541 women who did not report any discontinuation in the use of antiretrovirals after starting HAART. They found that “there were no significant differences by race in any of the outcomes assessed.”
Depression was identified as being associated with poorer virologic and immunologic response to HAART and death from any cause. Injecting drug use was found to be significantly associated with an increased risk of death due to AIDS.
Adherence was equally good in white, African American and Hispanic women with 73% of each racial group reporting 95% adherence or better.
“In our study investigating the relationship of race with response to HIV treatment in 961 women initiating HAART, white women had more favourable virologic, immunologic and clinical responses to HAART. The poorer response to HAART found in African American and Latina women, however, was explained largely by HAART discontinuation and to a lesser extent, by depression”, comment the investigators.
Anastos K et al. The association of race, sociodemographic, and behavioural characteristics with response to highly active antiretroviral therapy in women. J Acquir Immune Defic Syndr 39 (5): 537 – 544, 2005.