
Dual-energy x-ray absorptiometry (DEXA) is a procedure used to
analyze bone mineral structure and body fat distribution. DEXA
analysis uses low-energy X rays to measure mineral content in the
bones and body.
DEXA is also the name of a sub-study related to "Chemoprophylaxis for HIV Prevention in Men" (iPrEx).
The goal of the DEXA study is to identify the effects, if any, of Truvada® on mineral bone density or body fat distribution in healthy people not infected with HIV.
In people infected with HIV taking Truvada® and other medications used to treat HIV, the mineral density and strength of the bones may be changed. However, these changes did not cause a fracture or other problems to the patients.
We do not know if Truvada® reduces bone strength in healthy people not infected with HIV.
This substudy will also investigate whether taking Truvada® changes the distribution of fat in the body.
Understanding how Truvada® affects bone mineral density and body fat distribution in a healthy person may help other people that take Truvada® in the future.