APOE and Alzheimer disease: Moreover, Wong et al. (2019) and Liu et al. (2021) reported that Aβ is contributory, if not causal, in the differences observed in peripheral lipidomes between cognitive groups and Wong et al. (2019) describe differences in plasma lipidomes in healthy older adults based on apolipoprotein E status, a protein that binds and carries lipids and increases or decreases the risk of developing AD depending on the isoform.