October 26, 1994
The African American Study of Kidney Disease and Hypertension (AASK), the first major study of the most common kidney disease among Blacks, has added eight new clinics for the full trial. The $52 million, 7-year, full-scale phase follows a year-long pilot project.
More than 20 medical centers are participating in the Study, including all U.S. medical schools with a predominantly African American student body (Howard University, Meharry Medical College, Morehouse School of Medicine and Charles R. Drew University of Medicine and Science) and many major metropolitan hospitals with a predominantly Black patient population.
"The AASK Trial should tell us whether we need to treat blood pressure to a level lower than usually practiced, whether a specific class of blood pressure drug is required, or whether both are needed to slow or stop the progression of hypertension-related kidney disease in Black Americans," said Dr. Lawrence Agodoa, a kidney specialist at the National Institute of Diabetes and Digestive and Kidney Diseases, the study's primary sponsor. According to the National Kidney Foundation, 38 percent of Black Americans versus 29 percent of whites have hypertension, which increases the chance of developing kidney disease. But researchers believe race alone is a major risk factor.
African Americans make up 12 percent of the U.S. population but account for 29 percent of people treated for kidney failure. Hardest hit are Blacks aged 25 to 44, who are 20 times more likely than their white counterparts to develop hypertension-related kidney failure.
Improved control of hypertension has led to a decline in stroke and heart disease, but kidney disease due to hypertension is increasing. "We have some clues about what makes people prone to kidney disease, but we don't know why African Americans--even those with good blood pressure control--still are more susceptible," said Dr. Agodoa.
Patients in the AASK Study will be randomly assigned to either a low blood pressure goal (about 125/75) or a usual goal (about 140/90) and to one of three classes of antihypertensive drugs: either a calcium channel blocker (Amlodipine), beta blocker (Toprol), or angiotensin converting enzyme inhibitor (Ramipril). Neither patients nor their doctors will know which of these drugs is being used, and other drugs will be added as needed to reach blood pressure goals.
In 1991 nearly 5,600 Black Americans began treatment, probably dialysis, due to hypertension-related kidney failure. "We'd like to keep people from getting to that point. Dialysis saves lives but it doesn't give the same quality of life," said Dr. Agodoa.
And it is expensive. The average annual cost of treating kidney failure (dialysis and transplantation) is $47,000. Medical care for Black Americans with kidney failure due to hypertension costs Federal, state, and private insurers and patients about $1 billion each year, according to Agodoa.
Centers are finalizing study procedures and hope to ask about 1,000 patients to join the trial from January 1995 through December 1997. Patients will be followed until the year 2000. Results will be available in 2001.
Note to Editors:
The AASK Study is also funded by the Office of Research on Minority Health at the National Institutes of Health. Other important support comes from Astra USA, West Borrough, Massachusetts; Hoechst-Roussel Pharmaceuticals Inc., Pfizer Inc, New York City; and The Upjohn Company, Kalamazoo, Michigan.
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CONTACT:
Mary M. Harris
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