- known hypertension with a systolic BP (SBP) between 130-170 mm Hg at the previous visit to the internal outpatient department and at the last visit to the internist (which is the same day as baseline measurement) and treated with one or more anti-hypertensive drugs, which have not been changed for the preceding three months. At baseline the SBP should be between 140-160 mm Hg, measured by the investigator.