P1.09 MILD COGNITIVE IMPAIRMENT IS ASSOCIATED WITH SYSTEMIC VASCULAR DYSFUNCTION

Abstract

Aim: To evaluate vascular function and structure in subjects with mild cognitive impairment (MCI). Methods: 58 MCI and 22 controls (age 74±5vs75±4years, men 45vs59% p=ns) were recruited. Endothelial function in the brachial artery (BA) was studied by flow-mediated dilation (FMD) and response to glyceryl trinitrate, (GTN), while large artery stiffness was measured as carotid-femoral pulse wave velocity (PWV). Results: MCI and controls had a similar prevalence of established CV disease (14vs13%,p=ns) and traditional CV risk factors (hypertension 50vs54%, diabetes 13vs5%, dyslipidemia 28vs48%, smoking 4vs9%, p=ns for all). MCI showed higher blood pressure (BP) values than controls (pulse pressure 70±16vs62±12mmHg, mean BP 97±9vs91±8 mmHg, p<0.05 for both). PWV tended to be higher in controls compared to MCI (11.0±2.2vs9.9±2.4 m/s, p=0.07) but the difference was not significant after considering mean BP as covariate. MCI and controls showed similar BA diameter baseline shear rate (SR) and response to GTN. In MCI hyperemic SR and SR area under the curve were significantly lower (1591±831vs1175±673s−1, 29.7±15,8*103vs 21.1±14.9*103, p<0.05 for all) and time to peak was delayed compared to controls (50±16 s59±16s, p<0.05). Mean FMD values, allometrically corrected for baseline BA diameter, were significantly reduced in MCI (4.5±2.9vs2.7±2.9%, p<0.01). The difference remained significant after considering age, mean BP, and SR area under the curve as covariates (p<0.01). Conclusions: Patients with MCI showed a significant reduction in conduit artery endothelial function as well as in microcirculatory function. These data support the hypothesis that impaired systemic vascular function might hamper cognitive function.