Decomposing Racial and Ethnic Disparities in Risk and Protective Factors of Dementia in the U.S.

Objectives: This study investigates racial/ethnic disparities in dementia risk and protective factors using data from the Health and Retirement Study (HRS) and the Harmonized Cognitive Assessment Protocol (HCAP).

Methods: A retrospective analysis of 3,495 individuals aged 65+ from the 2016 HCAP linked to the HRS was conducted. Cognitive status was assessed using the Mini-Mental State Examination (MMSE) scores. Risk factors included midlife cardiovascular conditions, hearing loss, current smoking, depression, and physical inactivity. Protective factors were education and wealth. The Oaxaca-Blinder decomposition method was used to quantify the contribution of these factors in explaining racial/ethnic disparities in cognitive functioning.

Results: Black participants had 2.883 times higher odds of developing dementia compared to Whites, while Hispanic participants had 1.230 times higher odds (not statistically significant). Mid- and late-life risk and protective factors explained 32% of the cognitive gap between Black and White participants, and 70% between Hispanic and White participants, leaving 68% and 30% unexplained, respectively.

Conclusions: Addressing disparities in education, wealth, cardiovascular risks, depression, and hearing loss can reduce cognitive dysfunction in older adults.

Clinical implications: Clinicians should target modifiable risk factors like depression and physical inactivity, particularly in minority populations. Addressing socioeconomic disparities is also crucial for improving cognitive health.