Tuesday, May 3, 2011

Antiretrovirals: A Hairy Proposition

The title of this paper definitely caught my eye.

What if physicians could measure adherence to HIV medications by a method analogous to HgB A1C testing for diabetics? Enter antiviral concentration sampling in patients on HIV medications as a predictor of viral load suppression.

424 female participants (51% African-American, 31% Hispanic) contributed occipital hair samples for analysis of atazanavir concentration levels. After adjusting for age, race, treatment experience, pretreatment viral load, CD4 count and AIDS status, and self-reported adherence, hair levels were the strongest predictor of viral load suppression. Women with atazanavir levels in the highest quintile had odds ratios (ORs) of 59.8 (95% confidence ratio, 29.0-123.2) for virologic suppression. Adequate atazanavir hair levels predictive of viral suppression were > 1.78ng/mg of hair.  

Hair Sampling for Atazanavir Analysis-Clin Infect Dis 2011 May; 52(10):1267-75

Possible benefits of hair sampling:
 -Hair analysis provides a measure of average serum atazanavir concentration over weeks to months rather than a single point of time such as with a serum viral load
- Hair collection is simple and non-invasive and does not require specific skills and poses little risk for percutaneous injury or exposure to blood and body fluids
- Hair can be store for prolonged periods of time, without precautions for biohazardous materials

However, does this method work with other retrovirals and non-protease inhibitor based regimens?

Also, what if the patient suffers from severe alopecia (male pattern baldness)?

Must retrovirals be prescribed with Rogaine for maximal benefit of hair analysis?