Cognitive disorders in late life constitute an impending public health crisis that disproportionally impacts racial and ethnic marginalized adults. Older Hispanic/Latinx (henceforth, Latinx) adults have a one and a half times greater risk of developing Alzheimer’s Disease and Related Dementias (ADRD) than do their non-Hispanic White counterparts, and the number of older Latinx adults are projected to more than triple by 2060. Due to this projected population growth and the cohort’s already disproportionate risk for ADRD, Latinos are projected to have the largest increase in ADRD.
It is also necessary to recognize that the Latinx population in the United States is diverse in and of itself. Its diversity includes (but is not limited to) language preference, nativity and ethnic background. Mexicans or Mexican-origin adults make up more than 60% of the U.S. Latinx population, which is mostly concentrated in California, Texas and Arizona. Given the projected increased rates of ADRD and the proportion of Latinxs of Mexican-origin, investigating predictors of cognitive health risks and resiliency are needed.
Discrimination is a powerful social stressor that has negative consequences for mental and physical health outcomes in racial/ethnic marginalized adults. Cross-sectional studies have also linked experiences with discrimination to adverse cognitive outcomes in Black individuals (see also Johnson et al., 2020), but this link had not been examined in Latinx adults of Mexican-origin.
Our just published study tested whether higher levels of discrimination would be associated with cognitive functioning in Mexican-origin adults. Moreover, because chronic exposure to stress overtime can have detrimental effects on brain health, we also tracked longitudinal experiences with discrimination to discern the pattern of change in these experiences and examined if these trajectories were linked with cognitive function.
‘Mexicans or Mexican-origin adults make up more than 60% of the U.S. Latinx population.’
We leveraged data from a larger longitudinal study of Mexican-origin families in California and evaluated the responses from 1,110 parents in these families. Most of the parents were born in Mexico (85.87%), more than half were female (60.63%) and the average age at baseline was 38.18 (+/- 6.10).
Respondents provided information on their experiences of discrimination because of their ethnicity across five waves spanning 12 years. Using a scale from 0 (Almost never or never) to 3 (Almost always or always), they responded to items such as “You are treated with less courtesy than other people because you are Mexican/Mexican-American.”
In the 12th year of assessment, study participants also completed a cognitive battery that was composited into a total sum score. Our analyses controlled for age, education and baseline intelligence scores so that the associations were relative to a proxy of baseline cognition; additionally, we tested to see if associations varied by gender, nativity and language of interview.
Our results showed that higher levels of discrimination were concurrently associated with lower cognitive function in the twelfth assessment wave. We also observed an average gradual decrease in reports of ethnic discrimination across the 12 years.
There was significant variability in this average negative trajectory through which we were able to identify two subgroups of change trajectories: Stable Low and High Declining. The Stable Low class reported low levels of discrimination throughout the study period. The High Declining class had higher levels of discrimination at baseline, which declined throughout the study period, but throughout the study period had higher levels of ethnic discrimination compared to the Stable Low class.
The High Declining class had lower cognitive scores than the Stable Low class. We also found that those who chose to take the interview in Spanish (versus English) and who were born in Mexico (versus in the United States) were more likely to be in the Stable Low than the High Declining ethnic discrimination change group.
‘Greater acculturation (often measured via language of interview) is associated with greater exposure to discrimination.’
Overall, this study was the first to show that greater experiences with discrimination attributed to one’s ethnicity were associated with lower cognitive function, and that there is variability in experiences of ethnic discrimination within Mexican-origin adults living in the United States. Those who were born in Mexico and immigrated to the United States and who chose to take the interview in Spanish had lower exposure to discrimination across the study period compared to their counterparts.
On the flipside, those Mexican-origin adults who were born in the United States and chose to take the interview in English, reported greater discrimination throughout. This is in line with the literature showing that greater acculturation (often measured via language of interview) is associated with greater exposure to discrimination (see also Perez et al., 2009). On the contrary, there was some protection to discriminatory experiences among those who were presumably lower in acculturation—a finding that needs to be further investigated.
It could be, for example, that those who are less assimilated into the U.S. culture spend more time in communities that share their cultural background, whereas those who are more assimilated occupy less diverse spaces that exposes them to more discrimination.
In this Latinx/Hispanic heritage month (Sept. 15–Oct. 15), it is important to recognize that the Latinx culture is diverse in and of itself. Moreover, this study stresses the need for more research to better understand the diverse lived experiences of Latinx adults living in the United States.
Elizabeth Muñoz, PhD, is an assistant professor in the Department of Human Development and Family Sciences at The University of Texas at Austin College of Natural Sciences, and directs the Cognition, Health & Aging Research Team (CHART). She may be contacted at Elizabeth.Munoz@austin.utexas.edu.