Lower blood pressure goal benefits African-Americans with chronic kidney disease, protein in the urine
The study adds new information about which CKD patients benefit from the lowering of blood pressure, information that may help doctors practice evidence-based, personalized medicine, the tailoring of each treatment regimen to each patient's unique characteristics.
Akinso: A lower blood pressure goal was no better than the standard blood pressure goal at slowing progression of kidney disease among African Americans who had chronic kidney disease resulting from high blood pressure. However, the blood pressure goal did benefit people who also had protein in the urine, which is a sign of kidney damage. Dr. Griffin Rodgers, Director of the National Institute of Diabetes and Digestive and Kidney Diseases, explains that high blood pressure causes about one third of new cases of kidney failure.
Rodgers: The risk of kidney and heart disease—conditions that are often associated with longstanding hypertension—are far higher among people of African-American heritage than those of other racial or ethnic groups.
Akinso: Dr. Rodgers stresses the importance of long term studies like the African American Study of Kidney Disease and Hypertension, which is the largest and longest study of chronic kidney disease in African Americans.
Rodgers: The African American Study of Kidney Disease and Hypertension which is abbreviated AASK or A-A-S-K is an important long-term study that among other treatment modalities, compared standard with intensive therapy for hypertension close to 1100 African American patients with chronic kidney disease presumed to be due to hypertension.
Akinso: The AASK study, funded by the NIDDK, found that among people with protein in their urine, keeping blood pressure at the level reduced the likelihood of kidney disease progression, kidney failure, or death by 27 percent compared to standard blood pressure level, a statistically significant difference. Dr. Rodgers explains that the study was conducted in two phases.
Rodgers: First, in a clinical trial that ran between 1995 and 1998, participants were randomly assigned to standard blood pressure goal of roughly 140/90 or a lower goal and therefore a more intensive treatment with a blood pressure goal of 130/80. After the clinical trial was completed, most of the remaining participants were enrolled in a follow up study or the second phase of the study which began in 1998 and ended in 2010—current year. In which everyone had a blood pressure goal of less than 130/80.
Akinso: Dr. Rodgers explains the importance of the follow up study.
Rodgers: The phase two study was performed and in this follow-up study the recommended blood pressure therapy started with an angiotensin converting enzyme inhibitor, these are known as ACE inhibitors. This medication works by blocking the action of protein angiotensin, which raises blood pressure. And if blood pressure was not controlled, additional drugs were added. On average, patients required about 3.5 medications for blood pressure every day.
Akinso: Dr. Rodgers says for some patients, more intensive control of blood pressure may slow progression for chronic kidney disease.
Rodgers: The AASK study adds new information about chronic kidney disease patient's benefit from lowering their blood pressure. And this information may help doctors practice evidence-based personalized medicine, and the tailoring of treatment regimens for patients who have unique characteristics.
Akinso: Dr. Rodgers adds that people who participate in studies like AASK provide important information on how to protect the kidneys and preserve overall health. For information, visit www.niddk.nih.gov. This is Wally Akinso at the National Institutes of Health Bethesda, Maryland.
About This Audio Report
Reporter: Wally Akinso
Sound Bite: Dr. Griffin Rodgers
Topic: Disease, Hypertension, Chronic Kidney Disease, High Blood Pressure, Kidney failure