Inclusion CriteriaParticipants include those with essential hypertension and history of stroke who satisfy the following criteria:
- Onset of stroke(cerebral infarction/cerebral hemorrhage) occurred between 30 days and 3 years prior to the date of consent.
- Drug adherence is ≧80% during the screening period.
- Mean of 2 baseline BP measurements(measured at outpatient clinic) within 30 days prior to the date of consent is either 180 >SBP ≧130 mmHg or 110 >DBP ≧80 mmHg (untreated -3 anti hypertensive agents patients).
- Cerebral infarction with severity 3 or less in the modified Rankin scale.
Exclusion CriteriaPatient who meets any one of the following criteria is excluded from the study.
- Women who are pregnant, are possible pregnant, or are breastfeeding
- Possible secondary hypertension
- Severe hypertension (grade III or greater) with baseline SBP ≧180 mmHg or DBP ≧110 mmHg)
- Myocardial infarction or undergoing angioplasty occurred within 3 months prior to the screening.
- Current or previous heart failure with NYHA classification class III or more, or EF less than 35%
- Severe bilateral carotid stenosis or major cerebral artery occlusion
- Severe paralysis due to stroke (modified Rankin scale ≧ 4 )
- Current renal dysfunction (serum Cr ≧ 2.0 mg/dL right before the date of consent)
- Current hepatic dysfunction with AST or ALT value ≧ 100 IU/mL right before the date of consent
- Refractory hypertension treated with four or more antihypertensive drugs
- Hypersensitivity or allergy to losartan and other angiotensin II receptor blockers, hydrochlorothiazide, amlodipine or sulfonamide derivative
- Major surgery planned during the study period
- Participants of other clinical studies within the last 30 days
- Current malignancy (previous malignancy within 5 years after the end of treatment) excluding squamous-cell skin cancer
- Previous and current subarachnoid hemorrhage
- Definitive dementia 12) (based on a clinical diagnosis)
- Patients who have difficulty in signing consent or who do not agree to the provided consent
- Patients who are judged to be unsuitable for participating the study by the primary investigator or sub-investigator.