Brain vascular intima vulnerability among HIV-positive and negative individuals

Area of Science:

• Neurology
• Immunology
• Cardiovascular Science

Background:

• Human Immunodeficiency Virus (HIV) infection is a global health concern.
• Vascular complications, including those affecting the brain, are a significant cause of morbidity and mortality in individuals with HIV.
• The specific mechanisms by which HIV impacts the vulnerability of brain arteries remain incompletely understood.

Purpose of the Study:

• To investigate the association between HIV infection and the vulnerability of the intima in large brain arteries.
• To assess specific markers of intima vulnerability, including necrotic core size, elastolytic score, and inflammatory markers, in relation to HIV status.

Main Methods:

• A cross-sectional study was conducted using autopsied brain arteries from 302 individuals, with 50% being HIV-positive (HIV+) and matched to HIV-negative (HIV-) controls.
• Morphometric analysis evaluated atherosclerosis, necrotic core size, and fibrous cap thickness.
• Intima vulnerability was quantified using elastolytic and inflammatory scores, neoangiogenesis, and apoptosis markers.

Main Results:

• Atherosclerosis prevalence did not differ between HIV+ and HIV- groups.
• HIV+ individuals with CD4 counts >200 cells/μl showed larger necrotic cores in the intima.
• HIV+ individuals exhibited higher intima elastolytic scores, particularly those with CD4 counts <200 cells/μl, indicating increased connective tissue remodeling.

Conclusions:

• HIV infection is associated with increased intima vulnerability in brain large arteries, characterized by larger necrotic cores and enhanced elastolytic activity.
• These changes, particularly in individuals with lower CD4 counts, suggest a heightened risk for endothelial erosion, thrombosis, and plaque rupture, potentially leading to cerebrovascular events.