Hypertension in midlife adults is associated with cognitive decline later in life. In individuals treated for hypertension, blood pressure (BP) loads have been associated with end organ damages. This study examines whether BP load inversely correlates with performance in cognitive tasks in normotensive or controlled hypertensive (CHT) individuals.
Participants between 60 and 75 years old were divided into normotensive participants who did not receive antihypertensive treatment (n = 49) and CHT patients (n = 28). They were evaluated for BP using ambulatory blood pressure monitoring and cognitive functions with tests assessing cognitive flexibility, working and episodic memory, and processing speed.
Analysis of covariance between normotensive and CHT participants revealed lower cognitive performances on immediate and delayed recall and total number of words of the Rey Auditory Verbal Learning Test (P < 0.001). Spearman's correlations between BP loads and cognitive performances revealed inversed associations between diurnal systolic (SBP) loads and performances on the Trail Making Test Part B (TMTB) (P = 0.009), the TMTB–TMT Part A (P = 0.013), the Switching Cost of the color-word interference test (P = 0.020) and the Digit-Symbol Substitution Score tests (P = 0.018) in CHT. Diurnal diastolic (DBP) loads were inversely correlated to the TMTB (P = 0.014) and TMTB–TMT Part A (P = 0.006). In normotensive subjects, diurnal SBP loads were associated with the delayed recall of the Rey Auditory Verbal Learning Test (P = 0.031) and to the three components of the digit span (P < 0.05).
Diurnal BP loads are associated with lower cognitive performances in CHT individuals. These results suggest a lowering of target levels of diurnal BPs and/or its variability.