Follow-up study on patients with mild cognitive impairment by hydrogen proton magnetic resonance spectroscopy

Abstract

Objective To retrospectively analyze and investigate the conversion of cognitive function and characteristics of hydrogen proton magnetic resonance spectroscopy (1H-MRS) in patients with mild cognitive impairment (MCI).  Methods Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were used to assess the cognitive function of 75 MCI patients and 17 normal controls who were matched in sex, age and education with MCI patients. 1H-MRS was performed in the left hippocampus and left frontal lobe with 3.0T MRI respectively to evaluate related metabolites in the brain, including N-acetyl-aspartate (NAA), choline (Cho), creatine (Cr), myo-inositol (mI) and glutamate complex (Glx).  Results Compared with normal control group, the Glx/Cr ratio of left hippocampus and left frontal lobe in MCI group were significantly lower (P = 0.030, 0.030). By the end of follow-up, 7 of 75 subjects (9.33%) in MCI group had converted to Alzheimer's disease (MCI-AD subgroup), 55 cases (73.33%) had no change on their cognitive function (MCI-MCI subgroup), and 13 cases (17.33%) were considered returning to normal (MCI-normal subgroup). The Glx/Cr ratio of MCI-MCI subgroup was significantly higher than that of MCI-AD subgroup (P = 0.040). In normal control group, 13 cases (13/17) had no change on their cognitive function, and 2 cases (2/17) progressed into MCI. However, none of them converted to AD.  Conclusions The decline of Glx/Cr ratio in left hippocampus and left frontal lobe could possibly be the sensitive biological indicator of worsened cognitive function in MCI patients. Further study with enlarged samples and prolonged follow-up is still needed.

DOI: 10.3969/j.issn.1672-6731.2016.06.005