Background: Minorities' Diminished Return (MDR) theory suggests that socioeconomic position (SEP) may have a smaller effect on health and well-being of members of the minority than the majority groups. Aim: Built on the MDR theory, this study compared Whites and African Americans for the effects of three family SEP indicators (family type, parental education, and parental employment) during adolescence on subsequent symptoms of anxiety 18 years later during young adulthood. Methods: Flint Adolescents Study (FAS), 1994⁻2012, followed 359 youth (ages 13 to 17, 295 African American and 64 Whites) for 18 years. The independent variables were family type, parental education, and parental employment during adolescence. The dependent variable was subsequent symptoms of anxiety, measured using the Brief Symptom Inventory (BSI), 18 years later. Age and gender were the covariates and race/ethnicity was the focal effect modifier (moderator). Four linear regression models were estimated to investigate the effects of the three family SEP indicators at age 15 on subsequent symptoms of anxiety at age 33 in the pooled sample and also by race/ethnicity. Results: In the pooled sample, having married parents at age 15 was inversely associated with symptoms of anxiety at age 33. We found an interaction between race/ethnicity and family type, indicating a smaller protective effect of having married parents against symptoms of anxiety for African American compared to White participants. The other two SEP indicators did not show any effect and did not interact with race/ethnicity on the outcome. Conclusion: In support of the MDR theory, marital status of parents during adolescence protects White but not African American young adults against anxiety symptoms. Diminished return of SEP is one of many underlying mechanisms involved in shaping racial and ethnic disparities in anxiety, however, that is often overlooked. Future research that examines economic and social policies and programs that can equalize the health gains that follow SEP resources among racial groups would be a useful next step.
Keywords: African Americans; Blacks; anxiety; ethnic health disparities; populations; race/ethnicity; socioeconomic position.