Premature aging is striking in the brains of people infected with the virus that causes acquired immunodeficiency syndrome (AIDS).

A number of human immunodeficiency virus (HIV) patients surviving into their senior years are coming forward to express concerns about problems they're having with memory and other cognitive functions. An estimated 14 percent to 18 percent of all AIDS patients in the United States are more than 50 years old, and older people face one of the highest rates of new infections.

To investigate the interaction between HIV infection and aging and their effects on brain function, researchers from America studied 26 HIV infected people and 25 not infected individuals between the ages of 20 to 62 years. The researchers used functional magnetic resonance imaging (fMRI) scans to study the blood flow in the brains of all the subjects. The average age and education level of the HIV-positive and HIV-negative groups  were similar.

Both aging and HIV infection caused statistically significant decreases in baseline cerebral blood flow, but no interaction was present. 

The current study suggests that HIV infection and aging independently affect brain functional demands which may be due to patho-physiological similarities. Body frailty caused by aging and HIV infection may result from a complex interplay among viral factors, host responses, and immune dysfunction.