Associations Between Diabetes and Cognitive Function in Socioeconomically Diverse African American and White Men and Women.

OBJECTIVES: To examine whether race and poverty (income <125% of the federal poverty limit), modifies associations between diabetes and cognition in a biracial, urban-dwelling sample.
METHODS: Cross-sectional data for 2066 participants (mean age = 47.6 years, 56.8% women, 56.2% African American, 38.6% below poverty) from the first wave of the Healthy Aging in Neighborhoods of Diversity across the Life Span study were used for analyses. Eleven tests measured cognitive function. Interactions among diabetes, race, and poverty status with cognition were assessed in multiple regression analyses.
RESULTS: Significant interactions among diabetes, race, and poverty status were observed. Among African Americans below poverty, diabetic individuals performed lower than nondiabetic individuals on California Verbal Learning Test Free Recall Short Delay (z = -0.444 [0.123] versus z = -0.137 [0.045]) and Long Delay (z = -0.299 [0.123] versus z = -0.130 [0.045]), Digit Span Backward (z = -0.347 [0.109] versus z = -0.072 [0.041]), and the Brief Test of Attention (z = -0.452 [-0.099] versus z = -0.099 [0.047]), and higher on Category Fluency (z = 0.114 [0.117] versus z = -0.118 [0.044]). No consistent differences between diabetic and nondiabetic individuals were found for African American and white participants above poverty.
CONCLUSIONS: Diabetes was associated with poorer verbal memory, working memory, and attention among African Americans living in poverty. Diabetic African Americans below poverty may have increased risk of cognitive deficit at a younger age. Improving health literacy, doctor-patient communication, and multidisciplinary medical care for impoverished individuals may reduce differences. Additional research is needed to clarify mechanisms underlying these associations.