Angiotensin Converting Enzyme Inhibitor and ApoE4 on Alzheimers disease Lead Investigator: Wendy Wei Qiao Qiu Institution : Boston University School of Medicine E-Mail : wqiu67@bu.edu Proposal ID : 163 Proposal Description: Since ACE inhibitor inhibits Abeta degradation and the ACE inhibitor treatment on APP transgenic mice result conflicting results on the AD pathology, we aim to study the relationship between ApoE4, ACE inhibitor and AD by using the ADC longitudinal data. We hypothesize that the impact of ACE inhibitor on AD will be different between those with and without ApoE4 allele.