Abstract
BACKGROUND: We aimed to examine relationships between cumulative life-course burdens and trajectories of cardiovascular risk factors and midlife cognitive function in a longitudinal cohort of the Bogalusa Heart Study. METHODS: The study cohort consisted of 912 participants who had cognitive function measured in middle age, and body mass index, blood pressure (BP), atherogenic index of plasma, and LDLC (low-density lipoprotein cholesterol) examined 4 to 15 times from childhood to adulthood. Total and incremental area under the curve (AUC) were calculated as a measure of long-term burden and trend of risk factors, respectively. RESULTS: Trajectories of systolic BP were separated markedly around 25 to 45 years of age, with the group below the median of cognition score having higher levels of systolic BP than the group above the median. Adjusting for covariates, midlife cognitive function was associated with total and incremental AUCs of systolic BP. Standardized regression coefficients were -0.086 (95% CI, -0.161 to -0.010; P=0.027) for total AUC and -0.084 (95% CI, -0.144 to -0.017; P=0.007) for incremental AUC. These inverse associations were consistent across race and sex groups. Single measures of systolic BP in childhood and adulthood were not associated with midlife cognitive function. Single and long-term measures of body mass index, LDLC, and atherogenic index of plasma were not associated with midlife cognitive function, with the exception of the incremental AUC of body mass index. CONCLUSIONS: Data suggest that the impact of exposure to high BP on the brain accumulates across the lifespan. A life-course approach is superior in risk assessment for cognitive decline and dementia.