Plasma sphingolipid changes with autopsy-confirmed Lewy body or Alzheimer's pathology

Introduction: The clinical and pathological phenotypes of Dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) often overlap. We examined whether plasma lipids differed among individuals with autopsy-confirmed Lewy Body pathology or AD pathology. Methods: We identified four groups with available plasma 2 years before death: high (n = 12) and intermediate-likelihood DLB (n = 14) based on the third report of the DLB consortium; dementia with Alzheimer's pathology (AD; n = 18); and cognitively normal with normal aging pathology (n = 21). Lipids were measured using ESI/MS/MS. Results: There were overall group differences in plasma ceramides C16:0, C18:1, C20:0, and C24:1 and monohexosylceramides C18:1 and C24:1. These lipids did not differ between the high-likelihood DLB and AD groups, but both groups had higher levels than normals. Plasma fatty acid levels did not differ by group. Discussion: Plasma ceramides and monohexosylceramides are elevated in people with dementia with either high-likelihood DLB or AD pathology.