NEW YORK (Reuters Health) – Patients may be less likely to experience "white coat hypertension" if a nurse takes their blood pressure rather than a doctor, researchers report.
However, the best way to differentiate between white coat hypertension and true high blood pressure is to ask patients to wear a 24-hour ambulatory blood pressure monitor. This technique may be a more reliable and cost-effective way to test for hypertension than a single reading taken by either a doctor or a nurse, the investigators found.
About 10% of patients have resistant hypertension, which often leads to expensive tests and unnecessary prescriptions, according to the report in the December issue of the American Journal of Hypertension.
But taking blood pressure every few minutes over 24 hours in a patient's usual environment, or having a nurse rather than a doctor take the patient's blood pressure, can yield a more accurate measurement, Dr. Mark A. Brown from St. George Hospital in Kogarah, Australia, and colleagues found.
Their study included more than 600 patients with hypertension (greater than 140/90 mm Hg), as measured by a doctor. About 19% had been diagnosed with resistant hypertension and were taking at least three different medications.
But when these patients wore the monitoring device, more than one quarter of patients who had been diagnosed with resistant hypertension had normal blood pressure. Additionally, blood pressure readings were lower when taken by a nurse instead of a doctor.
For example, when a doctor recorded the pressure of a "white coat" hypertensive, it tended to add 16 to 26 points to the systolic pressure and 12 to 14 points to the diastolic pressure. When a nurse took the blood pressure, it added 9 to 17 points to the systolic reading and 4 points to the diastolic reading.
"This study shows that 2 to 3 of every 10 patients with apparent resistant hypertension have controlled blood pressure when this is assessed by 24-hour ambulatory blood pressure monitoring," the researchers report.
"Considering the high cost of investigations and treatments for secondary causes of hypertension, ambulatory blood pressure monitoring would seem a sensible initial investigation in patients with apparent resistant hypertension," Dr. Brown and colleagues conclude.