Neuroanatomical Changes Underlying Vertical HIV Infection in Adolescents

Abstract

Purpose: The aim of this study was to investigate how human immunodeficiency virus (HIV) affects brain development in adolescents, what are susceptible brain regions, and how these brain structural changes correlate with cognitive abilities. Methods: We used structural magnetic resonance imaging to examine gray matter volume and cortical thickness in 16 HIV-infected children (mean age = 13.63 years) and 25 HIV-exposed uninfected children (mean age = 13.32 years), 12 of them were subjected to a 1-year repetitive magnetic resonance scan of the brain. Five neurocognitive tests were performed on each subject to assess cognitive performance in different areas. Results: Cross-sectional studies showed that the gray matter volume of HIV-infected children was widely reduced (mainly in the bilateral frontal, temporal, and insular regions, and cerebellum). The changes in cortical thickness were mainly due to thinning of the right temporal lobe and thickening of the left occipital lobe. Longitudinal studies showed that the gray matter volume reduction of HIV-infected children after 1 year mainly occurs in the advanced functional area of the right prefrontal, parietal lobe and the motor area, cortical thinning of brain regions were sensorimotor cortex and the limbic system. The gray matter volume of the bilateral cerebellum was positively correlated with the performance of the Wisconsin Card Sorting Test, while the cortical thickness of the right dorsolateral prefrontal cortex was negatively correlated with this test. Conclusion: This study found that HIV-infected pubertal children showed a delayed cortical maturation with atrophy. This abnormal pattern of cortical development may be the structural basis for cognitive impairment in HIV-infected children.

Keywords: AIDS; HIV exposure; brain development; children; mother-to-child transmission; structural MRI.

Figure 1

Between-group comparison on gray matter volume (GMV). Clusters showing significantly (corrected P < 0.05) lower (blue) and higher (red) GMV in HIV+ children compared to controls. But the red region isn't successfully positioned in the template. This figure was rendered using BrainNet Viewer (http://www.nitrc.org/projects/bnv/).

Figure 2

Between-group comparison on cortical thickness (CT). Clusters showing significantly (corrected P < 0.05) lower (blue) and higher (red) CT in HIV+ children compared to controls. These figures were rendered using BrainNet Viewer (http://www.nitrc.org/projects/bnv/).

Figure 3

Longitudinal changes on gray matter volume (GMV) after 1 year. Clusters showing significantly (corrected P < 0.05) lower (blue) and higher (red) GMV changes after 1 year. (A) Clusters showing many lower and few higher GMV regions in HIV+ group children. (B) Clusters only showing significantly lower GMV regions in HEU group children. (C) Put together the two groups for statistical analysis and showing significantly changes of GMV after 1 year. (D) In assessing the time and interactions between the two groups, clusters showing widely areas of GMV significantly reduced. These figures were rendered using BrainNet Viewer (http://www.nitrc.org/projects/bnv/).

Figure 4

Longitudinal changes on cortical thickness (CT) after 1 year. Clusters showing significantly (corrected P < 0.05) lower (blue) and higher (red) CT changes after 1 year. (A) Clusters showing lower and higher CT regions in HIV+ group children. (B) Clusters showing significantly lower and higher CT regions in HEU group children. (C) Put together the two groups for statistical analysis and showing significantly lower regions more obviously than higher regions of CT after 1 year. (D) In assessing the time and interactions between the two groups, clusters showing widely areas of CT significantly reduced.