Abstract
BACKGROUND: Asymptomatic neurocognitive impairment (ANI) is the mildest form of human immunodeficiency virus (HIV)-associated neurocognitive disorders (HANDs), and functional connectivity strength (FCS) alternations have been observed in the ANI stage. However, it is not clear whether the FCS alterations are influenced by the anatomical distance. This study sought to investigate distance-specific FCS changes in HIV ANI patients. METHODS: In total, 29 patients with HAND and 32 healthy controls (HCs) were enrolled in the study. Between-group differences were detected for short, middle and long range anatomical distance FCS. A correlation analysis was performed to examine the relationship between distance-specific FCS and immunological parameters and neuropsychological tests. A receiver operating characteristic (ROC) analysis was conducted to examine the discriminative performance for HIV ANI patients. RESULTS: In comparison to the HCs, the HAND patients showed increased short-range FCS in the left inferior parietal lobule (IPL), middle-range FCS in the superior temporal gyrus (STG), long-range FCS in the left precuneus (PCC), and decreased FCS in the right postcentral gyrus (PCG) (cluster P<0.05, voxel significance P<0.001). Further, the long-range FCS in the right PCG was negatively correlated with the CD4/CD8 ratio (r=-0.479, 95% confidence interval (CI): -0.735 to -0.104, P=0.015), and the distance-specific FCS also showed good classification performance between the HAND patients and HCs. The left IPL, left STG, right PCG, and left PCC had areas under the curve (AUCs) of 0.875 [95% confidence interval (CI): 0.758-0.949, P<0.0001], 0.806 (95% CI: 0.677-0.900, P<0.0001), 0.855 (95% CI: 0.734-0.935, P<0.0001), and 0.852 (95% CI: 0.754-0.950, P<0.0001), respectively. There was no significant relationship between the distance-specific FCS and the neuropsychological tests. CONCLUSIONS: Distance-specific FCS could be used to examine subtle alternations in HIV-infected patients in the ANI stage and help to explain the possible neurophysiological mechanism of HAND.