More than a quarter of patients may have been misdiagnosed for high blood pressure, a finding that will see the way doctors identify hypertension changed for the first time in more than a century....Currently patients have a number of appointments to have their blood pressure checked, and it is estimated that 25% suffer from "white-coat hypertension" — a syndrome in which people show elevated blood pressure in a surgery or hospital but nowhere else.
....Although there is no debate over the existence of white coat syndrome, some researchers argue that even mild exercise can influence readings and patients should be at home when an assessment is made.
I can vouch for both of these. I have mild hypertension,1 but it turns into severe hypertension whenever I'm in a doctor's office: my blood pressure routinely registers 20 points higher there than anywhere else. The effect is so reliable that I don't even react anymore when attendants record my blood pressure before a visit and produce their usual startling results. Likewise, I discovered years ago that if I walked up to the local drugstore, my blood pressure registered 10-15 points lower on their machine compared to readings after driving over.
The British answer, apparently, is to make people wear a blood pressure monitoring system for a full day. My answer is to own a blood pressure monitor that's been checked and calibrated by my doctor. This works great and it only cost 50 bucks. But it only works great if you actually use it, and I guess that's a common problem. Perhaps 24-hour blood pressure boxes are in all our futures.
1Nicely controlled at the moment, thanks for asking.