Objective: Current guidelines stress the need for more than one measurement of blood pressure in the hypertensive patient. The frequency with which the first blood pressure significantly exceeds subsequent blood pressures (alerting response) is unknown. Participants in a hypertension treatment trial before initiation of therapy were included in post-hoc analyses to investigate the alerting response separately for trained nurse blood pressure measurements with mercury sphygmomanometer and measurements taken by an Omron 705 CP automated device.
Basic methods: A total of 313 participants were included. Each participant had three nurse blood pressure readings before a 24-h automated blood pressure monitoring device was attached, and three Omron measurements at the time the automated blood pressure monitoring device was removed. Alerting response was defined separately for systolic and diastolic measures as a decrease of > or =8 or > or =6 mmHg, respectively, from first measure to the average of the second and third measures.
Main results: An alerting response was observed in 20.4% of nurse-performed blood pressure measurements and 28.4% of Omron measurements. A large range of variation between first blood pressure and average second and third measures was observed, with changes of up to 30 mmHg systolic and 20 mmHg diastolic. The only demographic factor associated with the alerting response was body mass index, with obese patients more likely to exhibit an alerting response (P=0.004) in nurse-measured blood pressure.
Conclusions: We found the alerting response with both methods of blood pressure measurement; however, it was not consistently observed in the same individuals. This confirms that hypertensive patients require multiple blood pressure measurements.