Dr. Linda Gerber, a professor of public health and director of the Biostatistics and Research Methodology Core at Weill Cornell Medical College in New York, found patients who used the common diuretic drugs had, on average, lower blood pressure -- both systolic and diastolic -- than patients who did not receive them.
The study involved more than 600 black patients with uncontrolled hypertension.
Researchers at Weill Cornell and the Visiting Nurse Service of New York's Center for Home Care Policy and Research found fewer than half of black patients were prescribed a diuretic drug with proven benefits that costs just pennies a day.
"We were surprised to find that this beneficial and low-cost drug was not being prescribed for more patients who would benefit from it," Gerber said in a statement.
The researchers say the findings should be taken as a serious wake-up call for physicians who treat black patients for hypertension.
The findings were published in the American Journal of Hypertension.