Characteristics of cortical thickness in treated HIV-infected individuals with and without cognitive impairment

HIV can alter the brain structure and function in the early stage of infection. This study investigated the differences in cortical thickness patterns between healthy controls (HCs) and people living with HIV (PLWH) with asymptomatic neurocognitive impairment (ANI) or cognitive integrity (CI).

Twenty-one ANI, 25 CI, and 24 HCs were recruited and underwent high-resolution T1-weighted magnetic resonance images. Cortical thickness was analyzed using the Computational Anatomy Toolbox, and the correlation analysis was conducted between cortical thickness and clinical and neuropsychological variables.

Both CI and ANI exhibited decreased cortical thickness, primarily in the left frontal cortices and bilateral limbic system. ANI demonstrated a more pronounced and widespread pattern of cortical thinning. Lower CD4⁺ counts and higher peak plasma viral load were associated with decreased cortical thickness of the right pericallosal sulcus and middle-posterior part of cingulate gyrus and sulcus in ANI. Conversely, compared to HCs, both ANI and CI showed cortical thickening in the left insula cortex, and ANI tended to have a thicker cortex. Moreover, the increased thickness of left insula cortex in both CI and ANI were positively correlated with attention and working memory.

The cortical thickness thinning was observed in the frontal and limbic systems in both ANI and CI. Meanwhile, the thickening of the insular cortex may represent mild neuroinflammation or a transient compensatory mechanism. This study provides new insights into the neural mechanisms underlying HIV-related cognitive impairment and highlights the importance of cortical thickness alteration patterns when assessing cognitive function of PLWH.