Meynert nucleus-related cortical thinning in Parkinson's disease with mild cognitive impairment

Siming Rong; Yan Li; Bing Li; Kun Nie; Piao Zhang; Tongtong Cai; Mingjin Mei; Lijuan Wang; Yuhu Zhang

doi:10.21037/qims-20-444

Meynert nucleus-related cortical thinning in Parkinson's disease with mild cognitive impairment

Quant Imaging Med Surg. 2021 Apr;11(4):1554-1566. doi: 10.21037/qims-20-444.

Authors

Siming Rong¹, Yan Li¹, Bing Li¹, Kun Nie¹, Piao Zhang¹, Tongtong Cai¹, Mingjin Mei¹, Lijuan Wang¹, Yuhu Zhang¹

Affiliation

¹ Department of Neurology, Guangdong Neuroscience Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.

Abstract

Background: Cognitive impairment in Parkinson's disease (PD) involves the cholinergic system and cholinergic neurons, especially the nucleus basalis of Meynert (NBM/Ch4) located in the basal forebrain (BF). We analyzed associations between NBM/Ch4 volume and cortical thickness to determine whether the NBM/Ch4-innervated neocortex shows parallel atrophy with the NBM/Ch4 as disease progresses in PD patients with cognitive impairment (PD-MCI).

Methods: We enrolled 35 PD-MCI patients, 48 PD patients with normal cognition (PD-NC), and 33 age- and education-matched healthy controls (HCs), with all participants undergoing neuropsychological assessment and structural magnetic resonance imaging (MRI). Correlation analyses between NBM/Ch4 volume and cortical thickness and correlation coefficient comparisons were conducted within and across groups.

Results: In the PD-MCI group, NBM/Ch4 volume was positively correlated with cortical thickness in the bilateral posterior cingulate, parietal, and frontal and left insular regions. Based on correlation coefficient comparisons, the atrophy of NBM/Ch4 was more correlated with the cortical thickness of right posterior cingulate and precuneus, anterior cingulate and medial orbitofrontal lobe in PD-MCI versus HC, and the right medial orbitofrontal lobe and anterior cingulate in PD-NC versus HC. Further partial correlations between cortical thickness and NBM/Ch4 volume were significant in the right medial orbitofrontal (PD-NC: r=0.3, P=0.045; PD-MCI: r=0.51, P=0.003) and anterior cingulate (PD-NC: r=0.41, P=0.006; PD-MCI: r=0.43, P=0.013) in the PD groups and in the right precuneus (r=0.37, P=0.04) and posterior cingulate (r=0.46, P=0.008) in the PD-MCI group.

Conclusions: The stronger correlation between NBM/Ch4 and cortical thinning in PD-MCI patients suggests that NBM/Ch4 volume loss may play an important role in PD cognitive impairment.

Keywords: Parkinson’s disease (PD); cholinergic system; cognitive impairment; cortical thickness; nucleus basalis of Meynert.