Averaging multiple blood pressure (BP) measurements is recommended for hypertension (HTN) screening but can be impractical, especially in resource-constrained settings. We aimed to explore the implications of fewer BP measurements on BP classification and subsequent cardiovascular disease (CVD) risk.
We studied 8905 middle-aged participants without diagnosed HTN and quantified misclassified HTN (≥140/90 mmHg) by simplified BP approaches (e.g. single 1st BP, single 2nd BP, mainly 1st but 2nd BP if 1st was in a certain range) vs. the reference standard of the average of 2nd and 3rd BP. We also assessed CVD risk related to HTN status.
There were 823 participants classified as HTN by the standard approach. With single 1st BP, 2.8% of non-HTN were overidentified as HTN, and 18.3% of HTN were identified as not having HTN. The corresponding estimates with single 2nd BP were 2.1 and 6.4%. Similar estimates were seen when 2nd BP was used if 1st BP at least 130/80 (1.9 and 8.1%), with only 27.8% requiring 2nd BP. Two thousand, one hundred and seventy-eight CVD cases were documented in this population over 30 years. HTN by either the standard approach or any of the simplified approaches conferred higher CVD risk vs. consistent no HTN by both approaches.
In those without diagnosed HTN, a simplified BP measurement approach using the 2nd BP only when the 1st BP is at least 130/80 could reduce the total number of BP measurements by more than 50%, identify HTN with limited misclassification (2–8%), and predict CVD risks reasonably well.