Cumulative high blood pressure (BP) from young adulthood to midlife was found to be associated with worse midlife cognitive function and gait, independent of sociodemographic and vascular risk factors, according to a study results published in Circulation.
In this study, 191 individuals from the CARDIA study, a 30-year longitudinal study that followed a community-based cohort of young participants who were between the ages of 18 and 30 at the time of study initiation, were enrolled. Participants had serial in-person examinations at 2, 5, 7, 10, 15, 20, 25, and 30 years. The subcohort included in this study received gait and cognitive assessments at year 30, and 144 of the participants also had magnetic resonance imaging (MRI) data available to assess cerebral white matter hyperintensity (WMH). The summation of the area under the curve for all BP measurements taken between baseline and year 30 was used to determine cumulative BP. Multiple linear regression models were used to determine associations between cumulative BP and gait and cognitive assessments.
In the fully adjusted model, higher cumulative BP was associated with slower walking speed (P =.010 for systolic and diastolic cumulative BP), higher variability in gait (cumulative BP: systolic, P =.018; diastolic, P =.001), and shorter step length (cumulative BP: systolic, P =.011; diastolic, P =.005). Associations were also identified between higher cumulative systolic BP and worse scores on memory (P =.015), executive function (P =.021), and global domains (P =.010) of cognitive testing. High cumulative diastolic BP was found to be associated with a reduced score on memory assessment (P =.012). Associations were independent of socio-demographic factors as well as smoking status, diabetes, body mass index, and total cholesterol.
Participants were categorized into 2 groups, based on WMH detected on MRI (above and below median WMH; n=72 per group). Associations were identified between higher cumulative BP and higher WMH burden (cumulative BP: systolic: β=0.31; 95% CI, 0.06-0.56; diastolic: β=0.25; 95% CI, 0.006-0.50). WMH burden was found to have a moderating effect on the association between cumulative BP and gait (P <.05), but not significantly on the association between cumulative BP and cognitive function.
Study limitations include a possible lack of generalizability of the findings due to the sole inclusion of black and white participants, and the lack of assessment of changes in gait or cognition before the 30-year follow-up
“[H]igher BP exposure during young adulthood, even at levels below the clinical definition of hypertension, is associated with worse gait and cognition in mid-life, independent of other vascular risk factors,” concluded the investigators. “WMH burden moderated the association of cumulative BP with gait, but not with cognitive function. These results emphasize the impact of early life BP levels on brain structure and function and underscore the need for primordial prevention of high BP during early adulthood.”
Mahinrad S, Kurian S, Garner CR, et al. Cumulative blood pressure exposure during young adulthood and mobility and cognitive function in midlife [published online November 21, 2019]. Circulation. doi: 10.1161/CIRCULATIONAHA.119.042502