Tau pathologies mediate the association of blood pressure with cognitive impairment in adults without dementia: The CABLE study

INTRODUCTION: This study delineated the interrelationships among blood pressure (BP), cerebrospinal fluid (CSF) core biomarkers of Alzheimer's disease (AD), and cognition. METHODS: The linear regression analyses were conducted in 1546 non-demented participants (mean age of 61.58 years, range 40 to 89 years; 40% female; average days of BP measurement, 9.10 days). Mediation analyses with 10,000 bootstrapped iterations were used to explore the mediation effects. RESULTS: A clear age-related pattern of BP was delineated. Mid-life hypertension (especially systolic BP), late-life lower diastolic BP, as well as mid- and late-life higher pulse pressure were associated with cognitive impairment and tau-related biomarkers. BP variability was associated only with cognition but not with CSF biomarkers. Overall, the associations between BP and cognition were partially mediated (proportion: 11% to 30%) by tau pathologies, independently of amyloid pathology. DISCUSSION: Tau pathologies might play important roles in the relationship between BP and cognition, with significant age- and BP-type dependences.