For African Americans with kidney disease, large fluctuations in blood pressure from day to day are a warning sign indicating that they may face an increased risk of dying prematurely. That is the conclusion of a study appearing in an upcoming issue of the Clinical Journal of the American Society of Nephrology (CJASN). The findings highlight the importance of routine blood pressure monitoring in patients with kidney disease, and they suggest that treatments that address large fluctuations may improve health.
African Americans are more likely than whites to develop kidney disease. Doctors can find it difficult to predict which of their African American patients with kidney disease have the highest risk of dying prematurely; however, they do know that cardiovascular disease is most common cause of death in individuals with kidney disease and that there is a strong correlation between blood pressure and kidney disease progression.
To investigate the role of blood pressure in African American kidney disease patients' health, Ciaran McMullan, MD (Brigham and Women's Hospital) and his colleagues studied 908 African American adults who had kidney disease due to high blood pressure. The participants had at least one year of blood pressure measurements available, and they were followed for three to 6.4 years.
The researchers found that patients whose blood pressure changed significantly from day to day were nearly three times as likely to die from any cause during the study (and nearly six times as likely to die from heart-related problems) than patients whose blood pressure changed very little from day to day.
"Larger changes in blood pressure from day to day could identify a high risk group of African Americans with kidney disease," said Dr. McMullan. "In addition, it means that scientists should examine why people have large day to day variations in blood pressure, as this may turn out to be a new area of therapy research."
"This could mean that doctors should start paying attention not only to what the blood pressure is on the day you see him or her, but also on whether it is changing a lot each time he or she sees you," said Dr. McMullan.