Hypertension is highly prevalent risk factor for stroke, particularly for stroke associated with CSVD. Blood pressure (BP) lowering has been considered an important measure for preventing stroke and progression of CSVD. Moreover, uncertainty remains regarding the efficacy of folic acid therapy for secondary prevention of stroke because of limited and inconsistent data. We propose to conduct a randomized, double-blind, placebo-controlled, multicenter, 2×2 factorial designed clinical trial to test the primary hypothesis that 1) whether amlodipine folic acid is more effective than amlodipine in reducing the risk of all-cause stroke (including fatal and non-fatal stroke) over a follow-up period among patients with CSVD. 2) whether an intensive treatment strategy (a systolic BP target of <130mmHg) is more effective than a standard treatment strategy (a systolic BP target of 130-140mmHg) in reducing the risk of combined cardio-cerebrovascular events.~Both Intention-to-treat Analysis (ITT) and Per-protocol set (PPS) were used for analysis.~We will use Kaplan-Meier estimates of the cumulative risk of stroke (ischemic or hemorrhagic) event and combined cardio-cerebrovascular events during follow-up period, with hazards ratios and 95% CI calculated using Cox proportional hazards methods and the log-rank test to evaluate the treatment effect. All statistics will be 2-sided with P<0.05 considered significant, accounting for interim analyses.~All patients who received study drugs and with at least one safety follow-up record will be included in the safety population. The data for safety evaluation included adverse reactions observed during the trial and changes in laboratory data before and after treatment.
The primary objectives of this trial are:~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.~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.