Research has shown that African Americans and Hispanics are at increased risk of dementia, even when cardiovascular and socioeconomic factors are taken into account. What other factors contribute to poorer cognitive outcomes for these populations? A recent analysis of longitudinal data tested the hypothesis that psychosocial factors related to being a minority in the United States could be contributing to these groups’ poorer late-life memory trajectories.
This study of 10,173 individuals with an average age of 75 looked at psychosocial factors potentially related to the experience of being a minority to determine if any had an impact on memory trajectories over a six-year period. Factors included perceived discrimination, depressive symptoms, and external locus of control (a feeling of helplessness and lacking control). With a study this large, the researchers were able to statistically control for the following factors: age, sex, education, income, wealth and chronic diseases.
At the study’s outset, African Americans and Hispanics performed more poorly than white participants on memory tasks. Compared to other racial and ethnic groups in the study, African American participants reported significantly higher levels of perceived discrimination. At the start of the study, the researchers found that this predicted greater depressive symptoms, which in turn predicted lower memory scores. They also found that greater perceived discrimination for African Americans predicted greater external locus of control, which also then predicted lower memory scores.
For Hispanics, there was no association between their ethnicity and perceived discrimination. However, there was an association between Hispanic ethnicity and higher depressive symptoms and greater locus of control, both of which predicted poorer initial memory levels.
When looking at the rate of memory change over six years, being African American was again associated with greater perceived discrimination and predicted faster memory decline. However, when the impact of perceived discrimination was accounted for, African Americans were shown to have slower rates of memory decline. For Hispanics, the only association between ethnicity and memory decline came from the tasks that tested immediate recall.
For African Americans, this evidence suggests that combating discrimination could lead to better cognitive outcomes associated with age. Regarding Hispanics, further research is needed to determine predictors of the depressive symptoms and external locus of control that are associated with poorer cognitive outcomes.