Background: Alzheimer's disease and related dementias (ADRD) is a growing public health challenge. Prior research suggests that non-Hispanic whites (whites), non-Hispanic African Americans (African Americans), and Hispanics have differing risks for ADRD.Objective: To examine the existence of serious psychological distress (SPD) among whites, African Americans, and Hispanics; to calculate the predicted probability of ADRD in whites, African Americans, and Hispanics, and to decompose the differences among ADRD populations, quantifying the burden of higher SPD among African Americans and Hispanics, compared to whites.Data and Method: The authors use nationally representative data from the Medical Expenditure Panel Survey (2007-2015) to estimate the association between ADRD and race, ethnicity, and SPD. Using Blinder-Oaxaca decomposition analysis, the authors estimate to what extent higher SPD among Hispanics and African Americans was associated with higher ADRD rates compared to whites.Results: After controlling for individuals' demographic and socioeconomic characteristics and co-existing medical conditions, the presence of SPD was still significantly associated with a higher likelihood of having ADRD. The model predicted significantly higher likelihood of having ADRD among African Americans (7.1%) and Hispanics (5.7%) compared to whites (4.5%). Higher rates of having SPD among African Americans explained 15% of white-black difference and 40% of the white-Hispanic difference in ADRD rates, respectively.Discussion and Conclusion: Our findings suggest a significant relationship between SPD and ADRD and that the burden of SPD was greater among African Americans and Hispanics with ADRD. Efficient screening using self-reported SPD, compared to simply using diagnoses codes of mental illness, may be more helpful to reduce racial and ethnic disparities in ADRD. [ABSTRACT FROM AUTHOR]