CD4 and AIDS: This is in agreement with observations made by Ray et al. (2006), who noticed that a decrease in the CD4 count was associated with an increase in spending; this increase was statistically significant for patients whose CD4 counts fell within 50-199 cells/ μL (p=0.003).These observations lead us to confirm the economic advantage of tri-therapy, which is currently recommended as treatment for HIV/AIDS patients [6, 7, 29–32].