Carotid intima-media thickness in HIV-infected individuals: relationship of premature atherosclerosis to neuropsychological deficits?

Background: Intima-media thickness (IMT) measured by extracranial duplex sonography is a surrogate marker for atherosclerosis. It is well known that IMT is greater in HIV patients than in age-matched healthy controls due to HIV- induced endothelial damage and metabolic side-effects of antiretroviral therapy. However, it remains unclear whether atherosclerosis has an additional impact on cognitive function in HIV patients. Therefore, the objective of this study was to investigate the correlation between IMT and neuropsychological deficits in HIV patients.

Methods: 47 HIV patients and 40 age-matched healthy controls were examined by extracranial ultrasound 2 and 3 cm before the flow divider to evaluate differences in IMT. Possible neuropsychological deficits in HIV patients were assessed using a battery of 10 neuropsychological tests. Results of neuropsychological tests and markers of disease severity were correlated with IMT in HIV patients.

Results: IMT was significantly greater in patients than in healthy controls (p < 0.001). However, none of the neuropsychological tests correlated significantly with IMT measurements in HIV patients. There was only a weak correlation between deficits in attention and IMT in HIV patients (r = 0.44; p = 0.005), which was non-significant after correction for multiple comparisons. Markers of disease severity (CD4 cell count, HIV load in plasma, duration of HIV disease) did not correlate with IMT either.

Conclusion: IMT was greater in HIV patients compared to age-matched controls but it appears that premature atherosclerosis has no additional impact on the evolution of neuropsychological deficits in HIV patients. IMT did not correlate with the severity of immunodeficiency.