2. Lying and standing blood pressure will be measured twice, in the right arm using Dinamap™ (Critikon, UK), after resting for 10 minutes. Hypertension will be defined according to WHO criteria (systolic blood pressure (sBP) >140 mm Hg and/or diastolic blood pressure (dBP) >90 mm Hg or if the patient is on current antihypertensive treatment.