Hypertension is divided into three levels: I. Grade 1 hypertension refers to systolic blood pressure at 140-159 mmHg and diastolic blood pressure at 90-99 mmHg; II. Grade 2 hypertension refers to systolic blood pressure at 160-179 mmHg and diastolic blood pressure at 100-109 mmHg; III. Grade 3 hypertension refers to systolic blood pressure ≥ 180 mmHg and diastolic blood pressure ≥ 110 mmHg. Risk factors for hypertension include the following: i. age > 55 years for men and > 65 years for women; ii. history of smoking, impaired glucose tolerance and impaired fasting glucose; iii. dyslipidemia, total cholesterol ≥ 5.7 mmol/L or LDL > > 3.3 mmol/L; iv. family history of early-onset cardiovascular disease; v. abdominal obesity, waist circumference ≥ 90 cm for men and ≥ 85 cm for women; vi. blood homocysteine elevation.