Aging
Estimated effect of APOE-ε4 genotype on risk of dementia over 13 years of follow-up in a diverse cohort of Asian and White older adults in California Yingyan Wu* Yingyan Wu L. Paloma Rojas-Saunero Yixuan Zhou Natalie Gradwohl Taylor M Mobley Willa D Brenowitz Thomas J Hoffmann Kacie D Deters Rachel A Whitmer Paola Gilsanz Gilbert C Gee Ron Brookmeyer Elizabeth Rose Mayeda
The APOE-ε4 allele is one of the most recognized risk factors for dementia in non-Latino Whites, but there is a reduced association found in Black and Hispanic groups and the evidence is limited for Asian American ethnic groups. Dementia incidence and the prevalence of APOE-ε4 carriership appear to be lower among Asian Americans than non-Latino Whites. This study aims to estimate the effect of the APOE-ε4 carriership on dementia incidence across Chinese, Japanese, Filipino, and non-Latino White older adults in Northern California. We followed 1,073 Chinese, 841 Japanese, 584 Filipino, and 42,802 non-Latino White members of the genotyped Genetic Epidemiology Research in Adult Health and Aging (GERA) cohort (mean age 70 at enrollment) via electronic health records from Kaiser Permanente Northern California from 2002-2020. APOE-ε2/ε4 carriers were excluded. We estimated the effect of APOE-ε4 genotype (carrier/non-carrier) on dementia incidence for each racial/ethnic group using adjusted average cumulative incidence curves from pooled logistic regression models including APOE-ε4, follow-up time (and an interaction term with APOE-ε4), age at baseline, and sex. Death was treated as a censoring event. Risk differences and risk ratios (RRs) at 13 years of follow-up are presented; 95% confidence intervals (CI) were obtained with bootstrapping. Prevalence of APOE-ε4 carriership was similar among Japanese (20.4%) and non-Latino Whites (22.6%) and slightly lower among Chinese (17.0%) and Filipino (13.2%) older adults. APOE-ε4 carriership was associated with higher dementia incidence in all racial/ethnic groups, with RRs (CI) ranging from 1.47 (0.79-2.54) among Filipinos to 1.91 (1.35-2.60) among Japanese. Patterns were similar on the absolute scale (Figure). Prevalence of APOE-ε4 carriership varied across racial/ethnic groups, but the association between APOE-ε4 carriership and dementia incidence was similar across groups on both the relative and absolute scales.
