The African American Study of Kidney Disease and Hypertension (AASK): new findings

Abstract

In September, 2000, the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health called an early halt to the amlodipine arm of the African American Study of Kidney Disease and Hypertension (AASK) trial after careful deliberation by an independent data and safety monitoring board. An interim analysis of the AASK at 3 years revealed a renoprotective effect of the angiotensin-converting enzyme inhibitor ramipril as compared to the dihydropyridine calcium channel blocker (DHP-CCB) amlodipine in patients with mild to moderate renal insufficiency. This differential effect was independent of the blood pressure (BP) levels reached and was evident in proteinuric patients and suggestive in patients with baseline proteinuria < 300 mg/d, but was not conclusive. The AASK trial data suggest that DHP-CCBs should be used cautiously in the presence of mild to moderate renal insufficiency. Judgment should be reserved for the use of other CCBs, such as verapamil or diltiazem, since these are fundamentally different CCBs with the potential for a different impact on hypertensive nephrosclerosis. The blinded observation period for AASK will be completed at the end of September, 2001, at which time additional, clinically useful information is expected to become available. (c)2001 Le Jacq Communications, Inc.

Figure 1

Clinical trial profile for the African American Study of Kidney Disease and Hypertension (AASK) Trial. Adapted with permission from JAMA. 2001;285:2719–2728. ⁶

Figure 2

Blood pressure response to ramipril and amlodipine at baseline, 3 months into treatment, and in follow‐up after month 3 in the African American Study of Kidney Disease and Hypertension (AASK) Trial. Blood pressure values at baseline and during treatment did not differ between treatment groups. SBP=systolic blood pressure; DBP=diastolic blood pressure. Adapted with permission from JAMA. 2001;285:2719–2728. ⁶

Figure 3

Relative risk reduction for glomerular filtration rate (GFR) events (a confirmed reduction in GFR by 50% or by 25 ml/min/1.73 m² from the mean of the two baseline GFR determinations), progression to end‐stage renal disease (ESRD), or the composite of GFR events, ESRD, or death. Adapted with permission from JAMA. 2001;285:2719–2728. ⁶