Age-dependent nonlinear relationship between hypertension and hippocampal volume in sedentary women with lower educational attainment

BACKGROUND: This study investigated the age-dependent nonlinear relationship between hypertension stages, hippocampal volume, and cognitive performance in sedentary women with lower educational attainment. MATERIALS AND METHODS: Forty-four women (40-60 years) with low education and physical activity levels underwent Magnetic Resonance Imaging brain scans and cognitive tests. Hippocampal volumes were analyzed using CAT12 and SPM12. RESULTS: Age-dependent relationships between systolic blood pressure (SBP) and hippocampal volume were observed. In ages 40-49, higher SBP correlated with more minor left hippocampal volumes (r = -0.5937, P = 0.0046). In ages 50-59, greater SBP is associated with larger hippocampal volumes (left: r = 0.7040, P = 0.0002; right: r = 0.5885, P = 0.0031). Hippocampal measurements accounted for 48.2% and 70.3% of SBP variance in younger and older groups, respectively. Higher SBP correlated with poorer cognitive performance in Flanker (reaction time: χ² = 13.87, P = 0.003; accuracy: χ² = 31.36, P <.001) and N-back tasks (reaction time: χ² = 11.63, P = 0.009; accuracy: χ² = 22.20, P <.001). CONCLUSION: These findings challenge the 'lower is better' blood pressure paradigm, especially in older adults, suggesting the need for age-specific hypertension management and brain health preservation strategies. Public health implications include developing tailored interventions considering age, education, and physical activity; implementing age-specific blood pressure guidelines; integrating cognitive screenings into hypertension care; and creating targeted health literacy programs. Future research should establish causality, explore mechanisms, and evaluate personalized strategies for this vulnerable population.