BACKGROUND: High blood pressure (BP) may be associated with impaired cognitive function. BP is comprised of a steady (mean arterial pressure; MAP) and pulsatile (pulse pressure; PP) component. The purpose of this study was to examine the relationship between steady and pulsatile BP and cognition among adults ≥60years old.
METHODS: 2058 adults age 60-85years from the 1999-2002 NHANES were used in this analysis. MAP and PP were calculated from brachial BP as 1/3 systolic +2/3 diastolic BP, and systolic - diastolic BP, respectively. Cognition was assessed using the digit-symbol substitution test (DSST).
RESULTS: Unadjusted multiple regression revealed although PP independently predicted DSST score (β=-0.21, p<0.05), MAP was only predictive when entered simultaneously with PP (β=0.06, p<0.05). Further adjustments for sociodemographics and medical history significantly improved prediction of DSST score (∆R(2)=0.37, p<0.05), and removed the association between MAP and DSST score, although PP remained a significant predictor (β=-0.07, p<0.05).
CONCLUSIONS: PP, but not MAP, was significantly and inversely related to cognitive function among a representative sample of adults aged ≥60years after controlling for sociodemographic information and medical history.