APOE ε4 and Alzheimer's disease biomarkers in an American Indian community.

INTRODUCTION

Apolipoprotein E (APOE) ε4's effect on Alzheimer's disease (AD) depends on ancestry and environmental risk factors. The APOE ε4-AD link in American Indian (AI) populations appears attenuated, with current understanding largely informed by a single research study. This study seeks to extend this evidence in an AI population in Minnesota.

METHODS

Cross-sectional analysis of APOE ε4, medical comorbidities, and AD plasma biomarkers with 182 tribal elders.

RESULTS

Median age was 67; 70% were female; median Mini-Mental State Examination score was 29. Age-, sex-, and chronic kidney disease-adjusted log odds ratios with 95% confidence intervals for APOE ε4 carrier status on amyloid beta 42/40, tau phosphorylated at threonine 217 (p-tau217), and glial fibrillary acidic protein (GFAP) were 0.86 (0.80 to 0.94), 1.04 (0.87 to 1.25), and 1.00 (0.86 to 1.16).

CONCLUSION

Compared to non-Hispanic White populations, APOE ε4 has an attenuated effect on p-tau217 or GFAP in AI tribal elders. Limitations of this study include survival bias and race-associated differences in social determinants of health that can influence the observed results.