Successful blood pressure control in the African American study of kidney disease and hypertension

Background: The African American Study of Kidney Disease and Hypertension (AASK) is an ongoing trial to evaluate the effect of blood pressure and choice of antihypertensive drug on the rate of decline of renal function. Objective: To present the success of the AASK in achieving the trial's rigorous blood pressure goals in an extremely challenging patient population. Methods: The AASK participants included African American patients with hypertension (n=1094), aged 18 to 70 years, with glomerular filtration rates between 20 and 65 mL/min per 1.73 m(2) and no other identified causes of renal insufficiency. Participants were randomized to a goal mean arterial blood pressure (MAP) of either 102 to 107 mm Hg (usual MAP goal) or 92 mm Hg or less (low MAP goal). Participants in each of these groups were also randomized (double-blind) to a regimen containing metoprolol succinate, ramipril, or amlodipine besylate. Additional agents were added, if required, in the following recommended order: furosemide, doxazosin mesylate, clonidine hydrochloride, or hydralazine hydrochloride (or minoxidil, if needed). Results: In participants randomized to the low MAP goal, the percentage of participants who achieved a blood pressure of less than 140/90 mm Hg increased from a baseline of 20.0% to 78.9% by 14 months after randomization. For usual MAP goal participants, the corresponding percentages increased from 21.5% to 41.8%. The difference in median levels of MAP between the 2 MAP goal groups increased and remained at approximately 12 mm Hg. Blood pressure reduction was similar regardless of age, sex, body mass index, education, insurance or employment status, income, or marital status. Conclusion: The blood pressure goals set and achieved in AASK participants clearly demonstrate that adequate blood pressure control can be achieved even in hypertensive populations whose blood pressure is the most difficult to control.