P189Hypertensive exposure in relation to vascular brain injury and cognitive impairment using heart-brain magnetic resonance imaging; The Heart-Brain Connection Study

Abstract

Background: Hypertension is highly prevalent and considered an independent contributor to cognitive impairment, although the pathophy-siological mechanisms are complex and incompletely understood. Vascular brain injury induced by exposure of the cerebral microcirculation to increased pressure and pulsatility may be an important link between hypertension and cognitive impairment. Hypertensive cardiovascular remodeling as assessed by cardiovascular magnetic resonance imaging, e.g. aortic stiffness by pulse wave velocity (PWV), left ventricular mass index (LVMi) and left ventricular (LV) concentricity by mass-to-volume ratio, reflects hypertensive exposure and allows more in-depth investigation of hypertensive disease in relation to brain structure and function. Purpose: To investigate hypertensive exposure markers in relation to cerebral small vessel disease (CSVD) and cognitive impairment, using heart-brain magnetic resonance imaging. Methods: We included 559 participants aged 68 ± 9 years from the Heart-Brain Connection study, consisting of three patient groups (i.e. clinical diagnosis of heart failure, vascular cognitive impairment or carotid occlusive disease) and controls. Aortic PWV, LVMi, LV mass-to-volume ratio and CSVD (i.e. white matter hyperintensities, microbleeds, lacunar infarcts, perivascular spaces) were assessed by 3.0-T heart-brain magnetic resonance imaging. Impairment in ≥1 major cognitive domain was assessed by comprehensive neuropsychological testing. Effect modification by patient group was investigated by interaction terms; results are reported pooled or stratified accordingly. Results: Overall prevalence of CSVD was 68.7% and cognitive impairment 26.9%. Aortic PWV (odds ratio [OR] 1.17, p = 0.003 in patient groups only), LVMi (OR in carotid occlusive disease 5.69, p = 0.006; OR in other groups 1.30, p = 0.017) and LV mass-to-volume ratio (OR 1.81, p < 0.001) were all associated with CSVD. Both aortic PWV (OR 1.07, p = 0.009) and LV mass-to-volume ratio (OR 1.27, p = 0.007) were associated with cognitive impairment as well. All relations were independent of sociodemographics and cardiac index, and mostly persisted after correction for systolic blood pressure or medical history of hypertension. Presence of CSVD attenuated the relations between hypertensive exposure markers and cognitive impairment. Conclusion: Hypertensive exposure markers were independently associated with CSVD and cognitive impairment. Our findings indicate that hypertensive exposure markers relate to brain structure and function beyond clinical blood pressure or medical history.