The phenomenon of doctors recording higher blood pressure of a patient, than that of a nurse is known as the “White Coat Effect,” and is thought to result from the patient’s physical response to being assessed by a doctor. It has previously been noted in a number of studies, but these new findings offer the first comprehensive analysis of data to quantify this effect.
The research, from the University of Exeter Medical School (England) has found that blood pressure recordings taken by doctors are significantly higher then when the same patients are tested by nurses.
Dr. Christopher Clark, of the University of Exeter Medical School said the findings, published in The British Journal of General Practice should lead to changes in clinical practice. “Doctors should continue to measure blood pressure as part of the assessment of an ill patient or a routine check-up, but not where clinical decisions on blood pressure treatment depend on the outcome. The difference we noted is enough to tip some patients over the threshold for treatment for high blood pressure, and unnecessary medication can lead to unwanted side effects. Some patients may be erroneously asked to continue to monitor their own blood pressure at home, which can build anxiety. These inappropriate measures could all be avoided by the simple measure of someone other than the doctor taking the blood pressure recording.”
The research team measured blood pressure levels of 1,019 people. Measurements were taken by both doctors and nurses at the same visit. Dr. Clark added that the results came from different settings, across 10 countries, “So we can be confident that they can be generalized to any healthcare environment where blood pressure is being measured.” Science Daily 3/25/14