Arterial stiffness as an independent predictor of longitudinal changes in cognitive function in the older individual

Background Cognitive decline significantly contributes to disability in older individuals. We previously demonstrated cross-sectionally that arterial stiffness [pulse wave velocity (PWV)] was associated with memory loss independently of traditional cardiovascular risk factors and of neuroimaging findings in older individuals without prior stroke. The present study aimed to evaluate PWV as a predictor of longitudinal changes in cognitive function in older individuals reporting memory problems. Participants and methods We studied 102 older individuals (mean age 79 +/- 6 years; 31 men, 71 women) reporting memory problems. PWV was measured noninvasively by Complior. Traditional cardiovascular risk factor levels were measured. Global cognitive function was measured by the Mini-Mental State Examination (MMSE) (maximum score = 30) at baseline and at follow-up visit. Cerebral computed tomography evaluated the presence of microvascular damage or cortical atrophy. Individuals with prior stroke or atrial fibrillation were excluded. Results The baseline MMSE was 22.9 +/- 5.5; 61% were hypertensive, 26.8% diabetic, 9.4% smokers, 10.5% taking statins, and 21.1% taking nitrates. The average PWV was 13.5 +/- 2.2m/s. After a median follow-up of 12 months, the average per-year decline in MMSE was 2.9 points or 12.1%. Multiple regression models showed that PWV independently predicted cognitive decline ( model R-2 = 0.50). PWV was the single strongest predictor of cognitive decline, explaining 15.2% of the total variance (each 1m/s increase in PWV was associated with an average 0.74 per-year decrease in MMSE score, P < 0.001). Conclusion In older individuals, arterial stiffness ( PWV) is a strong predictor of loss in cognitive function, independent of age, sex, education, and traditional cardiovascular risk factors.