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Patients with chronic kidney disease (CKD) and renal transplant recipients (RTR) have increased cardiovascular risk. The value of measuring central pulse pressure (cPP) over brachial pulse pressure (pPP) is not known. Central PP was measured in 597 patients (364 CKD:233 RTR). In multivariate analysis, age and female gender positively correlated with cPP; heart rate and estimated glomerular filtration rate negatively correlated with cPP. Associations for age, heart rate and gender persisted after additional adjustment for pPP and aortic wave reflection. This model accounted for 91% of the variability in cPP, with pPP alone accounting for 74%. Results were similar when both patient groups were analysed separately. A subset of patients with CKD had aortic pulse wave velocity (PWV) and left ventricular mass index (LVMI) measured. There were no differences in the univariate correlations between PWV (r=0.368 vs 0.315; P=0.4) or LVMI (r=0.125 vs 0.163; P=0.7); nor in the multivariate models created for PWV (P=0.1) or LVMI (P=0.1) when either cPP or pPP were used. This study demonstrates that in these patients most of the variability in cPP can be explained by pPP. Additionally, cPP does not appear to provide additional information beyond pPP in determining PWV and LVMI. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) is now a recognized global public health problem. It is highly prevalent and strongly associated with hypertension and cardiovascular disease (CVD); far more patients with a glomerular filtration rate below 60 ml min−1 per 1.73 m2 will die from cardiovascular causes than progress to end-stage renal disease. A better understanding of the complex mechanisms underlying the development of CVD among CKD patients is required if we are to begin devising therapy to prevent or reverse this process. Observational studies of CVD in CKD are difficult to interpret because renal impairment is almost always accompanied by confounding factors. These include the underlying disease process itself (for example, diabetes mellitus and systemic vasculitis) and the complications of CKD, such as hypertension, anaemia and inflammation. Kidney donors provide an ideal opportunity to study healthy subjects without manifest vascular disease who experience an acute change from having normal to modestly impaired renal function at the time of uninephrectomy. Prospectively examining the cardiovascular consequences of uninephrectomy using donors as a model of CKD may provide useful insight into the pathophysiology of CVD in CKD and, therefore, into how the CVD risk associated with renal impairment might eventually be reduced. [ABSTRACT FROM AUTHOR]

Blood pressure is affected by situational anxiety, such as the white coat effect. We hypothesised that blood pressure would also be affected by anticipation of a blood test. Volunteer subjects were recruited on the campus of Birmingham University. Subjects were randomly assigned to intervention and control groups. After a period of rest, three seated blood pressure measurements were taken at l-rain intervals using an electronic sphygmomanometer. Between the second and third measurements subjects in the intervention group were told that a blood test would be carried out after the last measurement. No blood test was carried out. Three blood pressure measurements were made in all 213 randomised subjects. Analysis was by intentionto-treat. In the control group mean systolic and diastolic blood pressure fell in successive measurements. Between the second and third measurements mean systolic blood pressure fell by 1.4 mm Hg in the control group and rose by 2.6 mm Hg in the intervention group (difference 4.0 mm Hg, P < 0.0001). A rise in diastolic blood pressure between the second and third measurements did not reach statistical significance. It was concluded that anticipation of a blood test affects measured systolic blood pressure in volunteers. The practice of taking blood tests at the same time as measuring blood pressure may potentially bias estimations of blood pressure. [ABSTRACT FROM AUTHOR]