Figure Means and standard deviations of CERAD neuropathologic ratings of NPs and NFTs in the five groups and the four regions of interest

(A) ANCOVA comparing the five groups on NPs in the hippocampus, controlling for age at death, severity of dementia, and sex, approached significance (p = 0.057). Rate of NPs for those on combination therapy was lower than for the two monotherapy groups (p = 0.04). NFTs in the hippocampus did not differ between the groups (p = 0.66). (B) ANCOVA comparing the five groups on NPs in the entorhinal cortex had p = 0.003. Rate of NPs for those on combination therapy was lower than the two monotherapy groups (p = 0.009). NFTs did not differ between the groups in the entorhinal cortex (p = 0.89). (C) ANCOVA comparing the five groups on NPs in the amygdala had p = 0.009. Rate of NPs for those on combination therapy was lower than for the two monotherapy groups (p = 0.02). NFTs did not differ between the groups in the amygdala (p = 0.25). (D) ANCOVA comparing the five groups on NP sums in the cerebral cortex approached significance (p = 0.052). Rate of NPs for those on combination therapy was lower than for the two monotherapy groups (p = 0.04). NFTs did not differ between the groups in the cerebral cortex (p = 0.12). ANCOVA = analysis of covariance; CERAD = Consortium to Establish a Registry for Alzheimer’s Disease; NFTs = neurofibrillary tangles; NPs = neuritic plaques.