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The impact of multiple single day blood pressure readings on cardiovascular risk estimation: The Atherosclerosis Risk
Abayomi N Ogunwale1, Alanna C Morrison1, Wensheng Sun2
1The University of Texas Health Science Center at Houston, Texas, USA.
Insights
Using multiple blood pressure measurements within a single day significantly alters cardiovascular disease risk estimates. This highlights the impact of single blood pressure readings on predicting heart disease, heart failure, and stroke.
Area of Science:
- Cardiology
- Public Health
- Epidemiology
Background:
- Cardiovascular disease risk estimation guides therapeutic decisions.
- Systolic blood pressure (SBP) is a key factor in these estimations.
- Variability in SBP within a day can impact risk assessment accuracy.
Purpose of the Study:
- To quantify the change in estimated cardiovascular disease risk using multiple same-day blood pressure measurements.
- To assess the impact of different blood pressure measurement positions (sitting, supine, standing) on risk reclassification.
Main Methods:
- Analysis of 11,129 participants from the Atherosclerosis Risk in Communities study.
- Collection of multiple sitting, supine, and standing blood pressure measurements per participant.
- Comparison of cardiovascular disease risk estimates using different SBP values in established risk models.
Main Results:
- Replacing second sitting SBP with third sitting SBP reclassified 3.3%–5.1% for coronary heart disease, 1.9% for heart failure, and 2.7% for stroke risk.
- Replacing mean sitting SBP with mean standing SBP reclassified 5.4%–11.6% of participants.
- Individual risk estimates showed maximum upward and downward changes of 31% and 26%, respectively.
Conclusions:
- Estimated cardiovascular disease risks can fluctuate substantially within a day due to SBP variability.
- The use of a single SBP measurement may lead to misclassification of individual cardiovascular risk.
- Findings have significant implications for clinical practice regarding cardiovascular risk assessment.
Aims:
The aim of this study was to determine the magnitude of change in estimated cardiovascular disease risk when multiple same day blood pressure measurements are used in estimating coronary heart disease, heart failure and stroke risks.
Methods And Results:
Black and White participants, N = 11,129, enrolled in the Atherosclerosis Risk in Communities study (mean age 53.9 ± 5.7 (SD) years) were included. Each participant had three sitting, five supine, and six standing blood pressure measures during one day. Main outcome measures were changes in estimated coronary heart disease, heart failure and stroke risk when using the different blood pressure measures. Mean sitting, standing and supine systolic blood pressure values of the study population were 120.8 ± 18.6, 124.9 ± 20 and 124.7 ± 19.6 mmHg, respectively. The substitution of the second sitting systolic blood pressure with the third sitting systolic blood pressure (taken ∼5 min later) in two separate coronary heart disease risk models reclassified 3.3% to 5.1% of study participants. Similar substitutions for heart failure and stroke risk prediction models led to reclassification of 1.9% and 2.7% of participants respectively. When mean sitting systolic blood pressure was replaced with mean standing systolic blood pressure 5.4% to 11.6% of the participants were reclassified. Maximum upward and downward change in an individual's estimated risk was 31% and 26% respectively.
Conclusions:
Estimated risks of coronary heart disease, heart failure, and stroke for an individual can change significantly within a day due to changes in systolic blood pressure. Given recommendations to use estimated risk for therapeutic decisions, our study has implications for the use of a single systolic blood pressure in cardiovascular risk estimation.
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Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.
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Sites for measuring blood pressure
The Brachial Artery: Primary Site for Blood Pressure Measurement
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Prepare for the Procedure:

