Association Between Endothelial Function and Cognitive Performance in Patients With Coronary Artery Disease During Cardiac Rehabilitation

OBJECTIVE: Subtle cognitive deficits indicating early neural risk are common in the clinical presentation of coronary artery disease (CAD). Although deterioration may be mitigated by exercise, cognitive response to exercise is heterogeneous. Vasculopathy including endothelial dysfunction is a hallmark of CAD and may play an important role in impairing neural adaptation to exercise. This study aimed to assess peripheral measurements of endothelial function as predictors of cognitive performance in CAD participants undertaking cardiac rehabilitation (CR). METHODS: CAD patients (N = 64) undergoing CR were recruited for this prospective observational study. Neuropsychological and endothelial function assessments were performed at baseline and after 3 months of CR. Z-scores for overall cognitive performance and specific cognitive domains (verbal and visuospatial memory, processing speed, and executive function) were calculated. Endothelial function was measured by the reactive hyperemia index (RHI) using peripheral arterial tonometry. Cross-sectional and longitudinal associations between RHI and overall cognition were assessed using linear regressions and mixed models, respectively. Domain-specific associations were also explored. RESULTS: Although lower RHI was not associated with overall cognition at baseline (b = 0.26, p = .10), an increased RHI was significantly associated with an improvement in overall cognition (b = 0.55, p = .030) over 3 months. Lower RHI was associated with poorer verbal memory (β = 0.28, p = .027) at baseline and an increased RHI over 3 months was associated with an improvement in processing speed (b = 0.42, p = .033). CONCLUSIONS: RHI may be a clinically useful predictor of cognitive change and might provide insight into the etiology of cognitive dysfunction in patients with CAD.