 This pilot study will begin after the last scheduled AASK Cohort study visit. Eligible participants will be treated for 6 weeks on each of 3 antihypertensive regimens. The sequence of the regimens will be random. Each period of the three periods will have 2 visits, one visit at 3 weeks and one visit at 6 weeks. In the last week of each 6-week period, a 24-hour ABPM will be obtained. The primary outcome variable is nocturnal BP; each pair wise difference between the regimens will be calculated. 