24-h ambulatory pulse wave velocity and central blood pressure in type 2 diabetes

Abstract

BackgroundPulse wave analysis from a brachial cuff permits ambulatory measurements of pulse wave velocity (PWV) and central blood pressure parameters. The diurnal variation of PWV in type 2 diabetes is unknown. MethodsWe evaluated the Arteriograph24 which is a brachial cuff based equipment for estimating PWV and central blood pressure data without the use of a transfer function, in 22 type 2 diabetic patients, who had two 24 h measurements performed. ResultsThe mean number of valid day time and nighttime measurements were 29 (range 16–50) and 18 (11–25), respectively. 21 patients had at least one qualifying report. Nighttime PWV was significantly lower than during the day (9.1 vs. 9.7 ± 0.8 mm/s, p < 0.01). Systolic aortic blood pressure was 6 mmHg lower than brachial blood pressure in the day time (p < 0.01) and 4 mmHg lower during the night (p < 0.05). Each single measurement was standardized with the 24 h average as reference thus generating data from 1004 paired observations. The standardized PWV correlated with standardized values of heart rate (r = 0.24, p < 0.001) and systolic aorta blood pressure (r = 0.20, p < 0.001). A stepwise multiple regression model with standardized pulse wave velocity as dependent variable included standardized heart rate, systolic aorta blood pressure and a dummy variable for day/night status (R2 = 0.091, p < 0.001). ConclusionThe Arteriograph24 is applicable for research purpose. PVW in type 2 diabetes is modestly reduced during the night. The intraindividual variation of heart rate contributed independently to the variation of PWV.