Vulnerability to Hypertension Is a Major Determinant of Racial Disparities in Alzheimer's Disease Risk

Background Higher incidence levels of Alzheimer's disease (AD) in Black Americans are well documented. However, quantitative explanations of this disparity in terms of risk-factor diseases acting through well-defined pathways are lacking. Methods We applied a Blinder-Oaxaca-based algorithm modified for censored data to a 5% random sample of Medicare beneficiaries age 65+ to explain Black/White disparities in AD risk in terms of differences in exposure and vulnerability to morbidity profiles based on 10 major AD-risk-related diseases. Results The primary contribution to racial disparities in AD risk comes from morbidity profiles that included hypertension with about 1/5th of their contribution due to differences in prevalence (exposure effect) and 4/5ths to differences in the effects of the morbidity profile on AD risk (vulnerability effect). In total, disease-related effects explained a higher proportion of AD incidence in Black Americans than in their White counterparts. Conclusions Disease-related causes may represent some of the most straightforward targets for targeted interventions aimed at the reduction of racial disparities in health among US older adults. Hypertension is a manageable and potentially preventable condition responsible for the majority of the Black/White differences in AD risk, making mitigation of the role of this disease in engendering higher AD incidence in Black Americans a prominent concern.

Automated summary

The higher incidence of Alzheimer's disease in Black Americans is primarily attributed to differences in morbidity profiles and their effects on AD risk. Disease-related causes play a larger role in explaining AD incidence in Black Americans. Mitigating the impact of hypertension on the risk of AD in Black Americans is of significant importance.