The American Heart Association (AHA) has listed 7 common mistakes that may result in erroneously high BP measurement and an inaccurate diagnosis of hypertension. These include:

1. Having a full bladder can add 10-15 points to your reading.
2. Slouching, unsupported back or feet. Sitting with no support to back or feet can increase the BP reading by 6-10points. Make sure that the patient is sitting in a chair with back support and feet flat on the floor or a footstool.
3. Unsupported arm: While measuring BP, the arm should be placed on a table or flat counter, so that the measurement cuff is level with the heart. The BP reading increases by up to 10 points if the arm is hanging by the side or if it has to be held up to see the reading.
4. Sitting with crossed legs may increase a blood pressure reading by 2-8 points.
5. Wrapping the cuff over clothing increases reading by 5-50 points to your reading. So, the cuff should be applied over a bare arm. When taking a BP reading, the patient should be sitting comfortably in a chair, with legs uncrossed and feet flat on the floor and back and arm supported with the right-sized cuff applied over a bare arm.
6. Using a too small cuff increases BP reading by 2-10 points. Select the right size when measuring BP.
7. Answering questions, talking on the phone, etc. can add 10 points to the measured BP reading. Ask the patient to stay still and silent while the BP is being measured.

These factors may be the cause of white coat hypertension, where the BP reading is higher than normal or compared to those obtained via monitoring BP at home or in other out-of-office settings. Herein lies the significance of 24-hour ambulatory BP monitoring to accurately measure BP and confirm the diagnosis of hypertension.

(Source: AHA, April 30, 2018)