Xiaomo Xiong

Date of Award

Summer 2023

Document Type

Open Access Dissertation


College of Pharmacy

First Advisor

Z. Kevin Lu


Background: Alzheimer’s disease and related dementias (ADRD), an umbrella term to describe progressive neurodegenerative disorders linked to cognitive impairment and dementia, impose significant disease and economic burdens on the patients. Therefore, understanding the prevalence of these disorders is crucial, particularly for mild cognitive impairment (MCI), an intermediate phase between normal aging and dementia that may be reversible through early detection and intervention. Moreover, it is essential to identify the predictors of MCI to facilitate early detection. Additionally, addressing the existing health disparities in the prevalence and treatment of ADRD and MCI is imperative to help improve patients’ health outcomes. Meanwhile, given that patients with cognitive impairment may be more vulnerable to financial barriers to health access, understanding the potential impact of such barriers is crucial.

Objectives: The aims of this study were to (1) determine the trends of and disparities in the prevalence of MCI and dementia and to identify the associated factors for the detection of MCI; (2) identify gender disparities in the use of anti-dementia medications in patients with ADRD; and (3) investigate the impact of financial barriers to healthcare on health outcomes in patients with cognitive impairment.

Methods: For aim 1, we conducted a longitudinal study using data from Health and Retirement Study (HRS) (2006-2016). MCI and dementia were identified using the Langa-Weir classification of cognitive function. Multivariate logistic regression models were used to identify factors associated with the early detection of dementia. For aim 2, we conducted a cross-sectional study using data from the Medicare Current Beneficiary Survey (MCBS) 2016. Anti-dementia medications included cholinesterase inhibitors and N-methyl-D-aspartate (NMDA) receptor antagonists. Multivariate logistic regression models were implemented to determine the possible gender disparities in the receipt of anti-dementia medications. For aim 3, we conducted a cross-sectional study, using data from the National Health Interview Survey (NHIS), 2011 to 2017. Financial barriers to healthcare were identified using NHIS prompts. Health outcomes included health status, health care utilization, and economic burden. Logistic regression models were used to examine the impact of financial barriers to healthcare access on health outcomes.

Results: The 10-year average prevalence of MCI and dementia was 14.5% and 6.6%, respectively, with a decreasing trend in both MCI (from 14.9% to 13.6%) and dementia (from 7.4% to 6.0%). After controlling for other factors, non-Hispanic black (MCI: OR=2.83, P

Conclusion: This study found a decreasing trend in the prevalence of MCI and dementia in the past decade, and associated racial/ethnic and gender disparities among U.S. middle-aged and older adults. Also, gender disparities appear to exist in the use of anti-dementia medications among Medicare-insured patients with ADRD. Moreover, financial barriers to healthcare worsened health status and increased emergency department visits, hospitalization, and economic burden in patients with cognitive impairment.


© 2023, Xiaomo Xiong

Available for download on Sunday, August 31, 2025