HIV enters the brain soon after seroconversion and potentially causes cognitive impairment. Although the incidence of severe dementia has been reduced, perhaps due to effective HIV treatment, the prevalence of mild to moderate cognitive impairment appears to be increasing. It has been reported that 30-50% of HIV+ patients with well-controlled infections show cognitive deficits. Several factors are thought to contribute to this brain injury. However, the literature has yet to produce a clear consensus of the mechanisms that may underlie brain injury.

Brain volume loss associated with a history of severe HIV-related immunosuppression.

At NIST, we have utilized novel neuroimaging methods with complementary strengths, deformation-based morphometry, voxel-based morphometry and cortical modeling, to investigate the effects HIV has on brain structure and function. Here, we observed regionally specific patterns of reduced cortical and subcortical volumes in the HIV+ group. White matter loss and subcortical atrophy was related a history of more severe immunosuppression, while cortical thickness reductions were related to poorer neuropsychological test performance. The findings suggest that distinct mechanisms may underlie cortical and subcortical injury, and argues for the potential importance of early HIV treatment in protecting long term brain health.

Abstracts and Conference Presentations:

R. Sanford, A.L. Fernandez Cruz, L.K. Fellows, B.M. Ances, D.L. Collins, Regionally Specific Cortical Thinning in HIV+ Patients in the cART Era, 2016 Conference on Retroviruses and Opportunistic Infections (CROI), February 2016, Boston, Massachusetts (pdf)