Cognitive function and mental health: Findings from the Dallas Heart Study cohort

Purposes: 1) Explore the relationship between hypertension and cognitive functioning among older adults who participated in the second phase of the Dallas Heart Study (DHS-2) and the Dallas Hearts and Minds Study (DHMS); 2) Understand how cognitive functioning evolves among older adults who participated in the DHS-2 and DHMS; 3) Explore the relationship between depression symptoms and mild cognitive impairment in older African American and Caucasian adults who participated in the DHS-2 and DHMS. Methodology: Cross-lagged correlations determined relationships between hypertension, education, income, depression (measured using the Quick Inventory of Depressive Symptomology), and cognition (measured using the Montreal Cognitive Assessment) at baseline (DHS-2) and 12 years later (DHMS). Education, income, depression, and resting blood pressure were predictors, with change in cognition as the outcome variable. Multiple standardized correlation coefficients were compared to determine potential paths of relationship between variables across time. A paired samples t-test, with a significance of 0.05, was used to determine how depression and cognitive scores changed over 12 years within African Americans and Caucasians. Results: Participants with hypertension in the DHS-2 had lower scores of cognitive impairment in DHMS (β = .073, p = .026). Participants with lower educational attainment (β = .265, p = .006) and lower income levels (β = .210, p < .001) in the DHS-2 had lower scores of cognitive impairment in the DHMS. The same participants with more depression symptoms had more cognitive impairment in both the DHS-2 (β = -.170, p < .001) and the DHMS (β = -.113, p = .009), and participants with more depression symptoms in the DHS-2 had lower cognitive impairment scores in the DHMS (β = -.088, p = .009). Both African American and Caucasian participants with depression symptoms in the DHS-2 had significantly fewer depression symptoms in the DHMS when controlling for depression symptoms in the DHS-2 (p < .001). The same participants had significantly more cognitive impairment in the DHMS (p < .001). Conclusion: A diagnosis of hypertension may elicit negative changes in cognition over a 12-year period. Individuals from lower socioeconomic status (SES) communities may experience cognitive impairment 12 years later. The presence of depression symptoms may elicit negative changes in cognition over a 12-year period.