Longitudinal study of functional connectivity changes in asymptomatic neurocognitive impairment(ANI) in HIV- infected patients

Abstract Background: Asymptomatic neurocognitive impairment (ANI) stage is a critical stage for early diagnosis and treatment of HIV-associated neurocognitive disorder(HAND) disease, but there are few longitudinal studies on it. The changes of cognitive function and pathogenesis in HIV infected patients during this period remain unclear. Our objective was to evaluate changes in brain function after treatment in ANI patients based on amplitude of low frequency fluctuation(ALFF), amplitude of Low frequency fluctuation (fALFF), regional homogeneity(ReHo), and functional connectivity(FC) obtained by resting state functional magnetic resonance imaging(rs-fMRI). Methods: The study involved follow-up of 49 ANI HIV infected patients who underwent two rs-fMRI and neurocognitive tests with an average interval of 1.26 years. The ALFF/fALFF, Reho and FC changes between baseline group and follow-up group were discussed. Subsequently, correlations between rs-fMRI results and cognitive and clinical variables were analyzed. Results: Compared with baseline group, the follow-up group had a significant ReHo decrease in the left median cingulate and paracingulate gyri (DCG.L), right calcarine fissure and surrounding cortex (CAL.R), MOG.R and left precental gyrus(PreCG.L), as well as ReHo enhancement in the left supramarginal gyrus (SMG.L), right postcentral gyrus (PoCG.R), right parahippocampal gyrus(PHG.R) and left calcarine fissure and surrounding cortex (CAL.L)(FWE corrected, voxel-level P < 0.001, cluster-level P < 0.05). The results of ALFF/fALFF were not corrected by multiple comparisons, but decreased in MOG, supplementary motor area (SMA) and posterior central gyrus, and increased in amygdala and insula. The matrix diagram shows a statistically significant difference in connection reduction between CAL.L and PreCG.L and between CAL.R and MOG.RSome of the results of ReHo and FC were correlated with the results of cognitive tests. Conclusion: These findings suggest that abnormalities in the cingulate gyrus, peritalate cortex, and anterior central gyrus may indicate disease progression and cognitive decline, while abnormalities in the occipital lobe, visual center, and related functional connections should be of more concern. However, the increase of ReHo and FC in some brain regions may mean that the cognitive changes in ANI patients under treatment may be complex