A common phenomenon observed at our clinics is that patients with seemingly normal blood pressure (monitored at home) have an erratic increase in readings while visiting us. This phenomenon baffled physicians and patients for decades before it was coined medically as "white coat hypertension" pointing to the fact that patients have a sudden upsurge of blood pressure in clinics.
The medical cause can be attributed to the fact that a certain amount of diagnosis stress along with a sense of uncertainty may employ the body's stress hormones (eg-catecholamines) causing this surge. A few factors must be excluded before stamping the phenomenon as white coat like-
1 Mental relaxation before measuring BP
2 An empty bladder
3 A straight sitting posture
4 A properly calibrated BP measuring instrument (Analog or Digital doesn't matter)
5 Proper cuff placement along with proper circumference (Place the cuff on the bare upper arm one inch above the bend of the elbow. Make sure the tubing falls over the front center of the arm so that the sensor is correctly placed. Pull the end of the cuff so that it's evenly tight around the arm.)
6 No conversation
7 Multiple readings if doubtful in each arm at a period of 5 minutes from each measurement.
These steps will help ensure a near accurate blood pressure measurement and proper diagnosis. Don't put too much emphasis on a single erratic reading if the patient is not a known hypertensive.
White coat hypertension as was previously thought is not a benign condition and necessitates treatment as it increases risk of developing left ventricular hypertrophy of the heart as well as remodelling of myocardium.
The best way to judge these days is a new technique called ABPM (Ambulatory BP Monitoring) in which a patient's blood pressure is measured hourly during normal daily activities with the help of a small portable device affixed on any arm near the brachial artery and then tabulating the readings at the clinic. This also helps in diagnosing Masked hypertension and other phenomena like non dippers and reverse dippers which we shall perhaps discuss later.
A proper communication with the patient regarding his/her condition, risks and benefits is of paramount importance.
Meanwhile, monitor your blood pressure at regular intervals, keep notes, cut down your salt intake and consult your Clinicians regularly if you suffer from increased blood pressure (Hypertension).
Stay healthy, win over hypertension....
Dr Abhijnan Ghosh