Predictors of Cognitive and Functional Decline in Patients With Alzheimer Disease Dementia From Brazil

Abstract

Little is known on how risk factors for Alzheimer disease (AD) dementia affect disease progression, much less for populations with low mean schooling, whereas the transcription of APOE may be regulated by nongenetic factors. In this 44-month cohort study, 214 consecutive outpatients with late-onset AD were assessed for rates of cognitive and functional decline by way of Clinical Dementia Rating and Mini-Mental State Examination (MMSE) scores, keeping blinded assessment of APOE haplotypes. Subjects were evaluated for sex, schooling, age of dementia onset, and cerebrovascular risk factors (including Framingham risk scores). Of the 214 patients, there were 146 (68.2%) women and 113 (52.8%) APOE4+ carriers. The mean age of AD onset was 73.4±6.5 years-old, negatively correlated with time to Clinical Dementia Rating >1.0 (β=-0.132; ρ<0.001), MMSE=20 (β=-0.105; ρ<0.001), and MMSE=15 (β=-0.124; ρ=0.003), more significantly for women and APOE4+ carriers. Mean schooling was 4.18±3.7 years, correlated with time to MMSE=20 and MMSE=15 for women and APOE4+ carriers. Body mass index was correlated with time to MMSE=20 only for men (ρ=0.006). The 10-year coronary heart disease risk was correlated with time to MMSE=20 only for APOE4+ carriers (ρ=0.015). These outcomes suggest interactions among genomic effects of cognitive reserve, cerebral perfusion, and hormonal changes over mechanisms of neurodegeneration.