β-Amyloid (1–42) Levels in Cerebrospinal Fluid and Cerebral Atrophy in Mild Cognitive Impairment and Alzheimer's Disease

BACKGROUND Recent studies consistently reported Alzheimer's disease (AD) and, to a lower extent, mild cognitive impairment (MCI) to be accompanied by reduced cerebrospinal fluid (CSF) levels of β-amyloid. However, how these changes are related to brain morphological alterations is so far only partly understood. METHODS CSF levels of β-amyloid (1-42) were examined with respect to cerebral atrophy in 23 subjects with MCI, 16 patients with mild-to-moderateAlzheimer's disease (AD) and 15 age-matched controls by using magnetic resonance imaging and voxel-based morphometry (VBM). RESULTS When contrasted with the controls, β-amyloid (1-42) levels were significantly lower (p < 0.05) in patients with MCI and even more so in the AD patients. This effect was significantly associated with reduced gray matter densities in both the right and left hippocampal head based on the results of a VBM analysis across the entire sample. CONCLUSION Our finding confirms the results of previous studies and suggests that both the decrease in β-amyloid (1-42) and the development of hippocampal atrophy coincide in the disease process.