Invasively Measured Aortic Systolic Blood Pressure and Office Systolic Blood Pressure in Cardiovascular Risk Assessment in Chronic Kidney Disease

IntroductionCentral aortic blood pressure (BP) could be a better risk predictor than brachial BP. This study examined whether invasively measured aortic systolic BP improved outcome prediction beyond risk prediction by conventional cuff-based office systolic BP in patients with and without chronic kidney disease (CKD).MethodsIn a prospective, longitudinal cohort study aortic and office systolic BPs were registered in patients undergoing elective coronary angiography. CKD was defined as estimated glomerular filtration rate <60 ml/min/1.73 m2. Multivariable Cox models were used for the association with incident myocardial infarction (MI), stroke, and death.ResultsAortic and office systolic BPs were available in 39,866 patients (mean age: 64 years; 58% males; 64% with hypertension) out of which 6,605 (17%) had CKD. During a median follow-up of 7.2 years (interquartile range: 4.6-10.1 years), 1,367 strokes (CKD: 353), 1,858 MIs (CKD: 446) and 7,551 deaths (CKD: 2,515) occurred. CKD increased the risk of stroke, MI and death significantly. Office and aortic systolic BP were both associated with stroke in non-CKD patients (adjusted hazard ratios with 95% confidence interval per 10 mmHg: 1.08 (1.05–1.12) and 1.06 (1.03–1.09), respectively) and with MI in CKD patients (adjusted hazard ratios: 1.08 (1.03–1.13) and 1.08 (1.04–1.12), respectively). There was no significant difference between prediction of outcome with office or aortic systolic BP when adjusted models were compared with C-statistics.ConclusionRegardless of CKD status, invasively measured central aortic systolic BP does not improve the ability to predict outcome compared with brachial office BP measurement.