A new statistical means of assessing HIV-associated neurocognitive dysfunction (HAND) is more reliable than the so-called Frascati and Gisslén methods. Publishing their findings in the journal AIDS, researchers recruited 103 HIV-positive men who, thanks to antiretroviral treatment, had had a fully suppressed viral load for at least 12 months. They matched these men with 74 HIV-negative controls. All of the participants were at least 45 years old.

The investigators tested various facets of the men’s neuropsychological states and used the Frascati and Gisslén criteria to determine if the men had HAND. Then they used what is called the multivariate normative comparison (MNC) to compare the cognitive scores of each HIV-positive individual against the scores of the control group.

MNC is a statistical method that provides a more effective way of comparing an individual’s cognitive profile with the control group as a whole.

The HIV-positive men performed significantly worse in attention, information processing speed and executive function (which is an umbrella term for working memory, reasoning, problem solving and task flexibility) when compared with the control group. On the whole, men with HIV appear to have the symptoms of HAND at a greater rate than those without the virus.
 
According to the Frascati criteria, 48 percent of the HIV-positive men and 36 percent of the HIV-negative men had HAND, suggesting that the test is poor at identifying people who do not have HAND. The Gisslén criteria indicated that 5 percent of the HIV-positive men and 1 percent of the HIV-negative men had HAND, suggesting that this set of criteria can better eliminate people who do not have HAND, but is poor at identifying those who do have the condition.

MNC appeared to balance the apparent problems in the two other assessment methods, showing that 17 percent of the HIV-positive men and 5 percent of the HIV-negative men had HAND.

To read the study abstract, click here.