ACE and Alzheimer disease: In the absence of ApoE4, both central ACE inhibitor use (χ2 test: 21% versus 27%, p < 0.0001) and peripheral ACE inhibitor use (χ2 test: 13% versus 27%, p = 0.0002) were associated with a further reduced risk of developing probable and possible AD, considered together, compared with those not taking ACE inhibitors.