Cognitive performance and the thymus among HIV-infected subjects receiving HAART

To evaluate the impact of alcohol use, which is widespread in human immunodeficiency virus (HIV)+ individuals, on highly active antiretroviral therapy (HAART)-associated immune and cognitive improvements and the relationship between those two responses.

In a case-control longitudinal study, thymic volume, cognition, and immune responses were evaluated at baseline and after 6 months therapy in HIV+ and HIV- controls. Cognitive performance was evaluated using the HIV Dementia Score (HDS) and the California Verbal Learning Test (CVLT).

Prior to HAART, thymic volume varied considerably from 2.7 to 29.3 cm(3) (11 +/- 7.2 cm(3)). Thymic volume at baseline showed a significantly inverse correlation with the patient's number of years of drinking (r(2) = 0.207; p < 0.01), as well as HDS and the CVLT scores in both HIV-infected (r(2) = 0.37, p = 0.03) and noninfected (r(2) = 0.8, p < 0.01). HIV-infected individuals with a small thymic volume scored in the demented range, as compared with those with a larger thymus (7 +/- 2.7 vs. 12 +/- 2.3, p = 0.005). After HAART, light/moderate drinkers exhibited thymus size twice that of heavy drinkers (14.8 +/- 10.4 vs. 6.9 +/- 3.3 cm(3)).

HAART-associated increases of thymus volume appear to be negatively affected by alcohol consumption and significantly related to their cognitive status. This result could have important clinical implications.