Ming-Ching Wen1, Aloysius Ng1, Russell Jude Chander1, Wing Lok Au2, Louis C S Tan2, Nagaendran Kandiah3. 1. Department of Neurology, National Neuroscience Institute, Singapore. 2. Department of Neurology, National Neuroscience Institute, Singapore; Duke-NUS Graduate Medical School, Singapore. 3. Department of Neurology, National Neuroscience Institute, Singapore; Duke-NUS Graduate Medical School, Singapore. Electronic address: Nagaendran_Kandiah@nni.com.sg.
Abstract
INTRODUCTION: Existing literature on brain volumetric alterations in patients with Parkinson's disease (PD) have mainly focused on gray matter (GM) and are largely cross-sectional. Little is known about white matter (WM) volumetric features and their impact on cognitive symptoms in PD. Therefore, the present study aims to examine both GM and WM volumes of cognitively asymptomatic PD patients with a longitudinal design. METHODS: A total of 42 cognitively asymptomatic patients with early stage PD were recruited and followed up for 1.5 years. At follow-up, 12 patients progressed to mild cognitive impairment (MCI) and were classified as "converters" while the remaining 30 patients remained cognitively asymptomatic and were classified as "non-converters". All patients underwent clinical and neuropsychological assessments as well as MRI scans at baseline and at follow-up. RESULTS: At baseline, non-converters and converters had comparable cognitive scores. At follow-up, converters showed more deficits in frontal-related cognitive function than non-converters. Volumetric analyses revealed that converters had more longitudinal reduction in WM, but not GM, volume compared to non-converters. The decreased volumes among converters were mainly localized in the frontal areas. Moreover, baseline global WM volume significantly predicted conversion to PD-MCI, while baseline GM and WM volumes of the frontal and parietal regions were associated with frontal cognitive changes across time. CONCLUSION: PD patients who develop MCI demonstrate longitudinal reduction in WM volume, especially in the frontal areas. While both regional GM and WM volumes associate with frontal cognitive decline, baseline global WM volume may be a neuroimaging marker of conversion to PD-MCI.
INTRODUCTION: Existing literature on brain volumetric alterations in patients with Parkinson's disease (PD) have mainly focused on gray matter (GM) and are largely cross-sectional. Little is known about white matter (WM) volumetric features and their impact on cognitive symptoms in PD. Therefore, the present study aims to examine both GM and WM volumes of cognitively asymptomatic PDpatients with a longitudinal design. METHODS: A total of 42 cognitively asymptomatic patients with early stage PD were recruited and followed up for 1.5 years. At follow-up, 12 patients progressed to mild cognitive impairment (MCI) and were classified as "converters" while the remaining 30 patients remained cognitively asymptomatic and were classified as "non-converters". All patients underwent clinical and neuropsychological assessments as well as MRI scans at baseline and at follow-up. RESULTS: At baseline, non-converters and converters had comparable cognitive scores. At follow-up, converters showed more deficits in frontal-related cognitive function than non-converters. Volumetric analyses revealed that converters had more longitudinal reduction in WM, but not GM, volume compared to non-converters. The decreased volumes among converters were mainly localized in the frontal areas. Moreover, baseline global WM volume significantly predicted conversion to PD-MCI, while baseline GM and WM volumes of the frontal and parietal regions were associated with frontal cognitive changes across time. CONCLUSION:PDpatients who develop MCI demonstrate longitudinal reduction in WM volume, especially in the frontal areas. While both regional GM and WM volumes associate with frontal cognitive decline, baseline global WM volume may be a neuroimaging marker of conversion to PD-MCI.
Authors: Vincent Pozorski; Jennifer M Oh; Nagesh Adluru; Andrew P Merluzzi; Frances Theisen; Ozioma Okonkwo; Amy Barzgari; Stephanie Krislov; Jitka Sojkova; Barbara B Bendlin; Sterling C Johnson; Andrew L Alexander; Catherine L Gallagher Journal: Hum Brain Mapp Date: 2018-06-27 Impact factor: 5.038
Authors: Seok Jong Chung; Han Soo Yoo; Yang Hyun Lee; Hye Sun Lee; Byoung Seok Ye; Young H Sohn; Hunki Kwon; Phil Hyu Lee Journal: Hum Brain Mapp Date: 2019-05-14 Impact factor: 5.038
Authors: Tracy R Melzer; Daniel J Myall; Michael R MacAskill; Toni L Pitcher; Leslie Livingston; Richard Watts; Ross J Keenan; John C Dalrymple-Alford; Tim J Anderson Journal: PLoS One Date: 2015-12-29 Impact factor: 3.240