Relationship between APOE Genotype and Structural MRI Measures throughout Adulthood in the Study of Health in Pomerania Population-Based Cohort

BACKGROUND AND PURPOSE: The presence of the apolipoprotein E epsilon 4 allele is the strongest sporadic Alzheimer disease genetic risk factor. We hypothesized that apolipoprotein E epsilon 4 carriers and noncarriers may already differ in imaging patterns in midlife. We therefore sought to identify the effect of apolipoprotein E genotype on brain atrophy across almost the entire adult age span by using advanced MR imaging based pattern analysis. MATERIALS AND METHODS: We analyzed MR imaging scans of 1472 participants from the Study of Health in Pomerania (22-90 years of age). We studied the association among age, apolipoprotein E epsilon 4 carrier status, and brain atrophy, which was quantified by using 2 MR imaging based indices: Spatial Pattern of Atrophy for Recognition of Brain Aging (summarizing age-related brain atrophy) and Spatial Pattern of Abnormality for Recognition of Early Alzheimer Disease (summarizing Alzheimer disease-like brain atrophy patterns), as well as the gray matter volumes in several Alzheimer disease- and apolipoprotein E related ROIs (lateral frontal, lateral temporal, medial frontal, and hippocampus). RESULTS: No significant association was found between apolipoprotein E 84 carrier status and the studied ROls or the MR imaging based indices in linear regression models adjusted for age, sex, and education, including an interaction term between apolipoprotein E and age. CONCLUSIONS: Our study indicates that measurable apolipoprotein E related brain atrophy does not occur in early adulthood and midlife and suggests that such atrophy may only occur more proximal to the onset of clinical symptoms of dementia.