Cocaine dependence does not contribute substantially to white matter abnormalities in HIV infection

Abstract

This study investigated the association of HIV infection and cocaine dependence with cerebral white matter integrity using diffusion tensor imaging (DTI). 135 participants stratified by HIV and cocaine status (26 HIV+/COC+, 37 HIV+/COC−, 37 HIV−/COC+, and 35 HIV−/COC−) completed a comprehensive substance abuse assessment, neuropsychological testing, and MRI with DTI. Among HIV+ participants, all were receiving HIV care and 46% had an AIDS diagnosis. All COC+ participants were current users and met criteria for cocaine use disorder. We used tract-based spatial statistics (TBSS) to assess the relation of HIV and cocaine to fractional anisotropy (FA) and mean diffusivity (MD). In whole-brain analyses, HIV+ participants had significantly reduced FA and increased MD compared to HIV− participants. The relation of HIV and FA was widespread throughout the brain, whereas the HIV-related MD effects were restricted to the corpus callosum and thalamus. There were no significant cocaine or HIV-by-cocaine effects. These DTI metrics correlated significantly with duration of HIV disease, nadir CD4+ cell count, and AIDS diagnosis, as well as some measures of neuropsychological functioning. These results suggest that HIV is related to white matter integrity throughout the brain, and that HIV-related effects are more pronounced with increasing duration of infection and greater immune compromise. We found no evidence for independent effects of cocaine dependence on white matter integrity, and cocaine dependence did not appear to exacerbate the effects of HIV.

The Use of Visual Rating Scales to Quantify Brain MRI Lesions in Patients with HIV Infection

“…Moreover, greater anterior than posterior WMH burden is consistent with evidence that HIV is associated with frontostriatal compromise . Yet, DTI and morphometric studies commonly reveal widespread effects of HIV throughout the brain . Interestingly, it has been suggested that WMH may represent a more advanced form of white matter pathology than the subtler, more extensive forms detected by DTI .…”

“…31,32 Yet, DTI and morphometric studies commonly reveal widespread effects of HIV throughout the brain. [31][32][33][34][35][36][37][38] Interestingly, it has been suggested that WMH may represent a more advanced form of white matter pathology than the subtler, more extensive forms detected by DTI. 10,39 Future studies are needed to further clarify the clinical relevance of regional white matter lesions in HIV+ samples, as well as to examine the relation of WMH burden to DTI findings.…”

White Matter Changes in HIV+ Women with a History of Cocaine Dependence

“…Those widespread differences in diffusion metrics persist in our cohort despite cocaine abstinence could suggest that HIV is the primary driving factor of the neuropathology. Indeed, this idea is supported by results from a recent study showing no effect of current cocaine use on WM pathology in HIV+ subjects ( 20 ). However, it should be noted that Cordero et al’s recent findings differ from many those of studies demonstrating WM impairment in current cocaine dependence in the absence of HIV ( 15 – 17 ).…”

“…In one study, HIV-associated WM impairments in the DTI measure of mean diffusivity (MD) were found to be more severe in individuals with a history of substance abuse ( 19 ), providing preliminary evidence for a synergistic interaction of former substance abuse and HIV on WM pathology. However, another recent DTI study investigating the combined effect of current cocaine abuse and HIV on WM did not show a synergistic effect ( 20 ). In that study, Cordero and colleagues found no effect of current cocaine dependence on WM in both HIV+ and HIV− subjects ( 20 ), in contrast to a growing body of literature demonstrating WM impairment in current cocaine dependence ( 15 – 17 ).…”

“…However, another recent DTI study investigating the combined effect of current cocaine abuse and HIV on WM did not show a synergistic effect ( 20 ). In that study, Cordero and colleagues found no effect of current cocaine dependence on WM in both HIV+ and HIV− subjects ( 20 ), in contrast to a growing body of literature demonstrating WM impairment in current cocaine dependence ( 15 – 17 ).…”