Voxel-Based Morphometric Analysis of the Mini-Mental State Examination and the Mini-Mental State Examination-2 in Patients With Mild Cognitive Impairment and Alzheimer's Disease in Korea.

Abstract

Background: This study investigated the association between the Mini-Mental State Examination-2 (MMSE-2) and the Korean version of the Mini-Mental State Examination (K-MMSE) scores with global cortical gray matter volume changes in healthy older adults, patients with mild cognitive impairment (MCI), and Alzheimer's Disease (AD) in Korea. Using voxel-based morphometry analysis of structural magnetic resonance imaging (MRI), we explored how these correlations evolve with the progression of cognitive impairment. Additionally, we identified brain regions linked to the newly added components of MMSE-2, such as story memory and processing speed.

Methods: A total of 22 patients with MCI, 11 patients with AD, and 10 healthy controls were enrolled based on a comprehensive neuropsychological assessment. All participants underwent brain MRI within six months of completing both the MMSE-2 and K-MMSE. MRI data were acquired using T1-weighted three-dimensional spoiled gradient echo sequences on a Philips Intera Achieva 3.0T scanner. Image preprocessing and analysis were conducted using MATLAB and Statistical Parametric Mapping (SPM5). Multiple regression analysis was performed to compare gray matter volumes across groups, with adjustments for age and education. Statistical significance was set at P = 0.005 with a voxel threshold of 100, and brain atrophy regions were identified using Talairach Client 2.4.2.

Results: MMSE-2 scores demonstrated stronger and more extensive correlations with gray matter volume than K-MMSE scores. Specifically, MMSE-2: Brief Version was associated with the left fusiform gyrus and left inferior temporal gyri, while MMSE-2: Standard Version extended its correlations to include regions such as the hippocampus. Notably, MMSE-2: Expanded Version (EV) exhibited the most robust and widespread associations, involving frontal, temporal, and occipital regions. In contrast, K-MMSE scores showed more limited regional correlations, primarily focusing on the fusiform gyrus, hippocampus, and cuneus.

Conclusion: The MMSE-2 demonstrated broader and stronger associations with cortical gray matter volume compared to the K-MMSE. In particular, MMSE-2:EV emerged as a more effective cognitive screening tool in clinical settings due to its widespread correlations across key brain regions, including the frontal lobe-a region inadequately assessed by the K-MMSE. These findings highlight the enhanced sensitivity of MMSE-2 in detecting structural brain changes associated with cognitive decline.