Hair used to 'manage' Aids
2009-03-11 14:08
New York - A hair sample analysis
could be more effective than a blood test in determining if
anti-Aids drugs are effective in patients, researchers said.
Dr Monica Gandhi, of the University of California, San
Francisco, said blood levels may not reflect how well the
patient is adhering to treatment, and other factors such as
diet and medications can cause variability.
But hair samples reflect drug exposure over time.
"We ... plan to test this method in resource-limited
settings, such as in India or Africa, where blood collection
and (HIV) monitoring may be expensive and difficult," said
Gandhi, who reported the findings in the journal Aids.
She and her team measured anti-Aids drug levels in hair
samples from 224 women who were starting a new antiretroviral
regimen. Sampling required 10-20 hair strands, clipped close to
the scalp.
Hair drug levels
As hair levels of the drugs increased, so did the
likelihood that HIV levels were successfully reduced, the
report shows.
If hair drug levels are high, but HIV levels continue to
rise, it suggests that the virus may have become resistant to
the antiretroviral agents being used, Gandhi said.
If hair drug levels fall and HIV levels increase, it
suggests that either the patient is not adhering with treatment
or is using a new drug that is reducing the absorption of the
antiretroviral drug.
Gandhi's group also plans to examine the relationship
between drug levels in hair and side effects of the
antiretroviral drugs.
The purpose would be to see if some patients can lower
their dose of antiretroviral drugs to reduce rate of side
effects, while still having a treatment response, the
investigator explained.