Normal Cognitive Scores May Not Reveal HIV-Associated Brain Impairment

When the virus enters the nervous system it can affect attention, memory, and language.

HIV attacks the immune system and has the power to cause additional conditions — including neurocognitive disorders.

Headaches, confusion, and forgetfulness may appear to be unrelated to an infectious disease, but for some patients they are signs of HIV-associated neurocognitive disorders (HAND). This occurs when the virus enters the nervous system and affects attention, memory, and language, among other areas.

One study indicated that as much as 40% of patients with HIV suffer from HAND. Neuroscientists from the Georgetown University Medical Center discovered that even if a patient scores as normal, a brain scan can show that there is actually cognitive functions have been compromised.

“This could be due to the fact that some standard neuropsychology tests might be insensitive to HAND,” lead author Xiong Jiang, PhD, hypothesized in a news release.

The team looked at 14 adults with HIV from ages 52 to 64 — nine of which were on antiretroviral therapy which resulted in suppressed viral load.

The participants underwent standard neuropsychology tests consisting of face-gender or word-semantic tasks, like judging gender or meaning of a word. Functional magnetic resonance imaging (fMRI) was used and MRI images from two event-related scans were provided for each patient.

Participants with HIV did slightly worse on all of the standard tests when compared to uninfected controls, however, not statistically speaking. The authors confirmed that the patients with HIV adjusted to task changes significantly slower. This suggests brain dysfunction, specifically in the dorsal anterior cingulate cortex (dACC).

“Intriguingly, both impairments are highly prevalent in individuals with HIV-infection, suggesting dACC might be one of commonly affected brain regions in HIV and a potential neural target for therapies,” Jiang explained.

There was not a correlation between the fMRI and neuropsychology scores which indicates that brain scans are more sensitive than the standard tests, according to the analysis in AIDS Care.

“These findings, although preliminary, could have a significant implication for public health,” Jiang said.

For one, they suggest that older patients may be more likely to have HAND. The clinical implication here is that a normal cognitive score does not translate to no brain impairment, and clinicians may need to dive deeper.

“While there is no proven treatment that can effectively treat HAND other than control HIV replication, it is important for caregivers, families, and the individuals themselves to know if they are affected,” Jiang concluded.