As a risk factor for high blood pressure, low levels of potassium in the diet may be as important as high levels of sodiumespecially among African Americans, according to research being presented at the American Society of Nephrology's 41st Annual Meeting and Scientific Exposition in Philadelphia, Pennsylvania.
"There has been a lot of publicity about lowering salt or sodium in the diet in order to lower blood pressure, but not enough on increasing dietary potassium," comments lead author Susan Hedayati, MD, of the University of Texas Southwestern Medical Center in Dallas, Texas, and the Dallas VA Medical Center. The new study suggests that low potassium may be a particularly important contributor to high blood pressure among African Americans, and also identifies a gene that may influence potassium's effects on blood pressure.
The researchers analyzed data on approximately 3,300 subjects from the Dallas Heart Study, about half of whom were African American. The results showed that the amount of potassium in urine samples was strongly related to blood pressure. "The lower the potassium in the urine, hence the lower the potassium in the diet, the higher the blood pressure," says Dr. Hedayati. "This effect was even stronger than the effect of sodium on blood pressure."
The relationship between low potassium and high blood pressure remained significant even when age, race, and other cardiovascular risk factorsincluding high cholesterol, diabetes, and smokingwere taken into account.
Previous studies, including the landmark "Dietary Approaches to Stop Hypertension" study (DASH), have linked potassium deficiency to high blood pressure. The new results support this conclusion, and provide important new data on the relationship between potassium and blood pressure in a sample that was 50% African American. "Our study included a high percentage of African-Americans, who are known to consume the lowest amounts of potassium in the diet,
|Contact: Shari Leventhal|
American Society of Nephrology