Late-onset Alzheimer's disease (LOAD) is highly heritable; however, its estimated incidence across populations remains unclear. We computed family-based heritability leveraging Alzheimer's Disease Seq Show more
Late-onset Alzheimer's disease (LOAD) is highly heritable; however, its estimated incidence across populations remains unclear. We computed family-based heritability leveraging Alzheimer's Disease Sequencing Project pedigrees from non-Hispanic White (404 pedigrees), non-Hispanic Black (13 pedigrees), Dominican (100 pedigrees), and Dutch isolate (10 pedigrees), with four models incorporating age, sex, apolipoproten E epsilon4 (APOE ε4), and contributing study using two methods. Heritability estimates varied by method, model, and study populations. Statistical Analysis for Genetic Epidemiology (S.A.G.E.) estimates were highest for Dutch isolate (78.3%), followed by non-Hispanic Blacks (39.1%), Dominicans (31.7%), and non-Hispanic Whites (29.1%), adjusted for age and sex. APOE adjustment reduced estimates (4.9% on average), while study adjustment primarily affected groups that included multiple studies. Sequential Oligogenic Linkage Analysis Routines (SOLAR-Eclipse) estimates were higher (45.2% to 80.2%) than S.A.G.E. (20.4% to 80.9%) but behaved in parallel, except for the Dutch isolate. LOAD heritability estimates are dependent on study population and may reflect or indicate differences in LOAD risk by population. Show less
Kristiana Xhima, Julie Ottoy, Erin Gibson+21 more · 2024 · Alzheimer's & dementia : the journal of the Alzheimer's Association · Wiley · added 2026-04-24
Cerebral small vessel disease (SVD) and amyloid beta (Aβ) pathology frequently co-exist. The impact of concurrent pathology on the pattern of hippocampal atrophy, a key substrate of memory impacted ea Show more
Cerebral small vessel disease (SVD) and amyloid beta (Aβ) pathology frequently co-exist. The impact of concurrent pathology on the pattern of hippocampal atrophy, a key substrate of memory impacted early and extensively in dementia, remains poorly understood. In a unique cohort of mixed Alzheimer's disease and moderate-severe SVD, we examined whether total and regional neuroimaging measures of SVD, white matter hyperintensities (WMH), and Aβ, as assessed by Frontal WMH, occipital WMH, and Aβ were independently associated with smaller hippocampal volume. Frontal WMH had a spatially distinct impact on hippocampal shape relative to Aβ. In contrast, hippocampal shape alterations associated with occipital WMH spatially overlapped with Aβ-vulnerable subregions. Hippocampal degeneration is differentially sensitive to SVD and Aβ pathology. The pattern of hippocampal atrophy could serve as a disease-specific biomarker, and thus guide clinical diagnosis and individualized treatment strategies for mixed dementia. Show less