Small but important study about masked hypertension in Afro-Americans

While ACSH does not normally report on studies with small numbers of participants, the sound science recommendations from a new hypertension study transcend its size. According to Temple University researchers, a study of 32 generally healthy African American patients found that, over the course of three doctor’s visits, a little under half had a form of high blood pressure known as masked hypertension, which is when a patient’s blood pressure is found to be within a healthy range while at the doctor’s office but is higher when measured between visits. The researchers defined the condition as a daytime blood pressure reading of greater than 130/85 millimeters of mercury (mm Hg) and home measurement of greater than 120/70 mm Hg.

The results were presented this week at the 2011 American Society of Hypertension Scientific Meeting. Lead researcher Praveen Veerbhadrappa noted that masked hypertension is a known precursor to long-term high blood pressure and believes that office measurements of blood pressure cannot sufficiently identify masked hypertension in the African American population. ACSH's Dr. Gilbert Ross believes that “the results of this study convey an important message — whether it’s based on 32 participants or 32,000 — given the consequences of elevated blood pressure, such as stroke risk, kidney failure and heart failure.” He adds that, “for only about $50, you can purchase a home blood pressure measuring device that will enable you to monitor blood pressure at home at different times of day.” ACSH's Dr. Elizabeth Whelan agrees. “While it seems counter-intuitive that one’s blood pressure reading could be lower in the doctor’s office — contradicting the so-called ‘white coat’ effect," she says, "given that such visits can make patients nervous and thus drive up blood pressure, this is a known and widespread problem. Making home blood pressure measurement routine has the potential to save thousands of lives each year.”