Analyzing Genetic Factors Involved in Blood Pressure Changes Due to Salt and Potassium Intake (The GenSalt Study)

Inclusion Criteria: Inclusion Criteria for Primary Participants: * Between 18 and 60 years old * Systolic blood pressure level of 130 to 160 mm Hg and/or diastolic blood pressure level of 85 to 100 mm Hg * Both parents (2-generation nuclear family) or at least one parent (at least a 3-generation family) is available and willing to participate in the study * At least one sibling meets eligibility criteria for participation Inclusion Criteria for Sibling/Spouse/Child Participants: * Siblings and spouses must be between 18 and 60 years old; children must be more than 16 years old * Lives in the same village as the main study participant Exclusion Criteria for All Participants: * Current stage 2 hypertension (systolic blood pressure level greater than or equal to 160 mm Hg and/or diastolic blood pressure level greater than or equal to 100 mm Hg) * Current or recent (i.e., less than 1 month before the screening visit) use of antihypertensive medications or medications that affect blood pressure * Secondary hypertension * History of clinical cardiovascular disease, including heart attack, congestive heart failure, stroke, and peripheral arterial disease * Chronic kidney failure or urinary albumin concentration of greater than or equal to 20 mg/dL * Current diabetes (i.e., fasting serum glucose level greater than or equal to 126 mg/dL) or use of insulin or oral hypoglycemic agents * Peptic ulcer disease requiring treatment in the 2 years before study entry * Liver disease requ…