Reduced Gray Matter Volume in Subjective Cognitive Decline: A Voxel-Based Morphometric Study

Abstract

Background and Purpose Subjective cognitive decline has been proposed as a potential indicator of the preclinical state of Alzheimer's disease (AD). The results of the studies of cortical atrophy on brain MRIs in subjects with subjective cognitive decline are inconsistent across the literatures. We investigated whether subjects with subjective cognitive decline had less gray matter volume compared to controls without subjective cognitive decline as per brain MRI. Methods Thirty-six subjects with subjective cognitive decline and thirty-three controls without subjective cognitive decline were recruited retrospectively from among the patients who had visited the department of neurology at Inha University Hospital between January 2008 and December 2010. All subjects had undergone a brain MRI scan including 3D T1-weighted spoiled gradient recalled echo imaging. We used voxel-based morphometry (VBM) to examine gray matter volumes between the two groups, after controlling for age, sex, education, and total intracranial volumes (TIV). Results There were no significant differences in age, gender, education, and TIV between the two groups. In comparison to controls without subjective cognitive decline, subjects with subjective cognitive decline showed gray matter atrophy in the left superior and medial frontal gyri, left superior and inferior parietal lobules, and right precuneus and insular in the VBM analysis. Conclusions Individuals with subjective cognitive decline encountered in clinical settings have greater similarity to an AD gray matter atrophy pattern compared with cognitively normal individuals without subjective cognitive decline.