Hippocampal sLASER 1H-MRS in cognitively unimpaired elderly: Associations with APOE4, CSF p-tau181 and MR morphometry

The hippocampus, a vulnerable structure in Alzheimer’s disease progression, is one of the most challenging brain structures for 1H-MRS applications. To examine whether hippocampal metabolic dysfunction in cognitively normal elderly may contribute to disease pathology, we used a validated long-TE sLASER sequence to minimize macromolecular signal contamination and chemical shift displacement errors. We tested whether, after adjusting for age, metabolites were associated with APOE4 genotype, a risk factor for amyloid accumulation; and CSF p-tau181 and left hippocampal volume, indicators of tau burden and neurodegeneration, respectively. The main result was a statistically significant direct correlation between Glx and CSF p-tau181.