Folic Acid and Intensive Antihypertensive Therapy for Hypertension With CSVD

The primary objectives of this trial are: 1. Efficacy evaluation of amlodipine folic acid tablets: To assess the effects of amlodipine folic acid tablets 5.8 mg (5 mg amlodipine + 0.8 mg folic acid)versus amlodipine tablets 5 mg in preventing all-cause stroke in cerebral small vascular disease (CSVD) patients with hypertension and elevated homocysteine (Hcy) level. 2. Intensive Antihypertensive Therapy: To assess the effect of intensive antihypertensive therapy (SBP\<130 mmHg) versus standard antihypertensive therapy (SBP 130-\<140 mmHg) in reducing risk of combined cardio-cerebrovascular events in CSVD patients with hypertension and elevated Hcy level, using two basic anti-hypertensive drugs, amlodipine tablets 5 mg or amlodipine folic acid tablets 5.8 mg.