Effects of social adversity and HIV on subcortical shape and neurocognitive function

Abstract

The purpose of the current study was to examine the independent and interactive effects of social adversity (SA) and HIV infection on subcortical shape alterations and cognitive functions. Participants included HIV+ (n = 70) and HIV- (n = 23) individuals who underwent MRI, neurocognitive and clinical assessment, in addition to completing questionnaires from which responses were used to create an SA score. Bilateral amygdalae and hippocampi were extracted from T1-weighted images. Parametric statistical analyses were used to compare the radial distance of the structure surface to a median curve to determine the presence of localized shape differences as a function of HIV, SA and their interaction. Next, multiple regression was used to examine the interactive association between HIV and SA with cognitive performance data. An HIV*SA interactive effect was found on the shape of the right amygdala and left hippocampus. Specifically, HIV-infected participants (but not HIV-uninfected controls) who evidenced higher levels of SA displayed an inward deformation of the surface consistent with reduced volume of these structures. We found interactive effects of HIV and SA on learning/memory performance. These results suggest that HIV+ individuals may be more vulnerable to neurological and cognitive changes in the hippocampus and amygdala as a function of SA than HIV- individuals, and that SA indicators of childhood SES and perceived racial discrimination are important components of adversity that are associated with cognitive performance.

Keywords: Adversity; Amygdala; Cognition; Hippocampus; Human immunodeficiency virus; Structural neuroimaging.

Fig. 1

Area in blue represents the surface region where a significant HIV*Adversity interaction was observed. Fig. A shows the right amygdala and Fig. B shows the left hippocampus (seen from sagittal and coronal views, respectively). HIV+ participants with higher adversity scores evidenced the greatest atrophy of these regions

Fig. 2

Effect of Social Adversity Score on Amygdala Vertex Area in blue represents the surface region of the amygdala that was associated with social adversity

Fig. 3

a Amygdala shape correlations with cognitive domains (Figure a = left amygdala; Figure b = right amygdala). Green = attention/information processing speed; Yellow = learning/memory; Pink = verbal fluency; Blue = executive functioning Brown = motor functioning b Hippocampal shape correlations with cognitive domains (Figure a = left hippocampus; Figure b = right hippocampus). Green = attention/information processing speed; Yellow = learning/memory; Pink = verbal fluency; Blue = executive functioning; Brown = motor functioning.

Fig. 4

a Amygdala shape correlations with social adversity indicators (Figure a = left amygdala; Figure b = right amygdala). Green = financial strain; Yellow = current SES; Pink = childhood neighborhood SES; Blue = racial discrimination; Brown = current neighborhood SES b. Hippocampal shape correlations with social adversity indicators (Figure a = left hippocampus; b = right hippocampus). Green = financial strain; Yellow = current SES; Pink = childhood neighborhood SES; Blue = racial discrimination; Brown = current neighborhood SES.