Early-onset mild cognitive impairment in Parkinson’s disease: Altered corticopetal cholinergic network

Abstract

Degeneration of the substantia innominata (SI) is significantly correlated with cognitive performance in Parkinson’s disease (PD). We examined functional and structural patterns of SI degeneration in drug-naïve PD patients according to the duration of parkinsonism before mild cognitive impairment (MCI) diagnosis. Twenty PD patients with a shorter duration (PD-MCI-SD, <1 year), 18 patients with a longer duration (PD-MCI-LD, ≥1 year), and 29 patients with intact cognition (PD-IC) were included. Seed-based resting-state functional connectivity (rsFC) analysis using bilateral SI seed and region-of-interest-based volumetric analysis were performed. Compared to PD-IC, the collapsed PD-MCI group showed altered rsFC in the right frontal and bilateral parietal areas. PD-MCI-SD showed rsFC alteration in broader frontal and parietal areas compared to the other groups. Decreased rsFC in the right frontal area was also significantly correlated with shorter disease duration. No significant SI volume change was found between the groups. Altered rsFC between the SI and the frontal and parietal areas might be relevant to cognitive dysfunction in PD. Decreased rsFC between the SI and frontal area might be associated with early-onset MCI, suggesting that cholinergic deficits in the frontal brain areas might play an important role in the acceleration of cognitive decline in PD.

Altered Nucleus Basalis Connectivity Predicts Treatment Response in Mild Cognitive Impairment

“…This finding is well in line with the early neurodegeneration of the NBM and several PET studies showing a widespread reduction of acetylcholine activities in MCI (25,26). The results are also in broad accordance with two recent NBM FC studies in MCI (27) and MCI in Parkinson disease (28) showing reduced NBM FC associated with cognitive deficits. However, we found a more extended pattern of NBM FC deficit in MCI compared with Li et al (27), which may be related to our postprocessing method and the medication effects.…”

Functional connectivity of the nucleus basalis of Meynert in Lewy body dementia and Alzheimer’s disease

“…A similar shift from anticorrelation to positive correlations between the substantia innominata and parietal and occipital areas has previously been found in patients with Parkinson's disease and mild cognitive impairment (Kim et al, 2017). Furthermore, we found similar results in the DLB and PDD subgroups and we did not see any significant changes in AD patients compared to controls.…”

Bayesian variable selection in logistic regression with application to whole-brain functional connectivity analysis for Parkinson’s disease

“…Previous PD-related studies that leverage functional connectivity either only perform statistical analysis for detecting altered brain regions 12–14 or build a simple machine learning model based on rsFC acquired from predetermined discriminative regions of interest (ROI). 15 In this paper, we focus on utilizing the radiomics approach to extract the whole-brain rsFC for predicting PD without restricting our analysis to a few selected regions.…”

“…8 Applications of radiomics approach in the neurodegenerative and mental disorder have disclosed the heterogeneity characteristics with a high accuracy that facilitate individualized diagnosis in patients with Alzheimer's disease, autism spectrum disorder and schizophrenia. [9][10][11] Previous PD-related studies that leverage functional connectivity either only perform statistical analysis for detecting altered brain regions [12][13][14] or build a simple machine learning model based on rsFC acquired from predetermined discriminative regions of interest (ROI). 15 In this paper, we focus on utilizing the radiomics approach to extract the whole-brain rsFC for predicting PD without restricting our analysis to a few selected regions.…”