Efficacy of HAART in Women Versus Men

Efficacy of HAART in Women Versus Men

Despite the above differences in CD4 counts and viral loads between men and women, recent studies have shown that HAART is just as effective in women as it is in men. Early in the HIV epidemic, women with HIV seemed to progress faster to AIDS and death than men,¹⁶ most likely because of decreased HIV testing, access to antiretrovirals (ARVs) and HIV care, lower rates of medication adherence in HIV-positive women, and higher rates of IV drug use among women with HIV.

Disease progression to AIDS and death between men and women seemed to level out in the mid-1990s to early 2000s as more and more women were diagnosed with HIV and started on ARV treatment.¹⁷ In the current era, we are starting to see a new trend of better outcomes in women compared to men.¹⁸

The reasons for this trend are multifactorial and all are not well understood, although increased access to HIV testing and ARVs have definitely contributed. Women also tend to have higher levels of ARV medications in their blood than men, which may lead to improved responses to treatment. The consequence of higher drug levels than men, however, can also be a higher number of adverse effects.

Antiretroviral Drug Levels in Women Versus Men

Cross-sectional and small pharmacokinetic studies have shown that women tend to have higher levels of antiretrovirals in their blood than men.¹⁹ This may partially explain the recent trend of improved outcomes among women as more and more women have access to medications.

In addition, in the current era, it is possible that drug-experienced patients on antiretrovirals may have better outcomes when they have higher drug levels in their blood. There are many variables that contribute to how people's bodies process medications, many of which are affected by gender and hormones.

For example, women generally weigh less and will therefore often have higher plasma levels of ARVs at a given dose. Estrogen affects protein production in the body, which will affect drug levels because proteins often attach to drugs in the blood and carry them around. Men seem to clear antiretroviral medications more rapidly than women due to differences in kidney and liver function. In general, there are a multitude of reasons why women may have higher levels of HIV medications in their bloodstream and this fact may explain better treatment responses and higher rates of side effects.