White coat hypertension: when the doctor raises blood pressure
White coat hypertension is a temporary rise in blood pressure values when measured by a doctor.
What is white coat hypertension?
White coat hypertension happens in about 20% of people with high blood pressure. In these individuals, high blood pressure values are only observed when in the presence of a doctor or nurse or inside a hospital, and the blood pressure values return to normal levels when the subject leaves the hospital or medical facility. “White coat syndrome” therefore describes subjects who manifest higher blood pressure values in a clinical environment than in other situations. This condition was first observed thanks to the development of devices able to measure blood pressure over the course of a 24-hour period. Doctors can therefore request this analysis, known as “Ambulatory Blood Pressure Monitoring” (ABPM), to verify whether the elevated values observed with traditional measurement techniques persist throughout the day.
Is white coat hypertension harmless?
While white coat hypertension should not be considered a ‘normal’ phenomenon (as it does not happen to everyone), the risk associated with it is significantly lower than with stably high blood pressure. However, those who suffer from it can develop permanently high blood pressure over time. Therefore, while the diagnosis of white coat hypertension may not necessitate immediate pharmaceutical therapy, there is a risk that with the years, blood pressure may stabilize on high values. It is therefore important to regularly measure blood pressure and act upon other risk factors.
Find out more
This topic was discussed at the 19th Congress of the European Society of Hypertension (ESH) in Milan, directed by Dr. Giuseppe Mancia, who comments on the results emerged in a sub study of the PAMELA study, conducted on two thousand people in ten Centers in the Brianza area of Italy. There are people who observe normal blood pressure values when they measure it at home, but are surprised when their doctor observes values above the norm. These higher values are blamed on the emotion the patient experiences when confronted with a doctor, and the stress caused by fear of the doctor’s diagnosis. Dr. Giuseppe Mancia states the study showed that white coat hypertension should not be underestimated, as after a 10-year interval, those who suffered from white coat hypertension were three times more likely to develop stable hypertension.
This condition is known as white coat hypertension, although the more descriptive definition of “isolated clinical hypertension” has been suggested. This definition is preferable because the blood pressure increase detected through ambulatory monitoring is not the same as the increase connected to the presence of a doctor.
The available studies show that isolated clinical hypertension is present in 15 percent of the general population and is responsible for over a third of cases of hypertension. The diagnosis of isolated clinical hypertension should be associated with all patients whose clinical blood pressure is observed to be above 140/90 mmHg in at least three occasions, while the average blood pressure over 24 hours and the daily average values , observed through ambulatory monitoring, appear to be within a normal range.
Scientific articles below:
- White coat hypertension: improving the patient–health care practitioner relationship (Psychol Res Behav Manag. 2015; 8: 133–141.) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4427265/
- The 2015 Canadian Hypertension Education Program Recommendations for Blood Pressure Measurement, Diagnosis, Assessment of Risk, Prevention, and Treatment of Hypertension (Can J Cardiol. 2015 May;31(5):549-68) http://www.sciencedirect.com/science/article/pii/S0828282X15001300
- White-coat and masked hypertension are associated with carotid atherosclerosis in a general population: the Hisayama study. (Stroke. 2013 Jun;44(6):1512-7) http://stroke.ahajournals.org/content/44/6/1512.long
- Could Blood Pressure Phobia Go Beyond the White Coat Effect? (Am J Hypertens. 2015 Apr 7. pii: hpv040)