Use of Different Blood Pressure Thresholds to Reduce the Number of Home Blood Pressure Monitoring Days Needed for Detecting Hypertension
Corey Bradley, Eun Hee Choi, Marwah Abdalla, Hiroyuki Mizuno, Michael Lam, Maria Cepeda, Dona Sangapalaarachchi, Justin Liu, Paul Muntner, Kazuomi Kario, Anthony J. Viera, Joseph E. Schwartz, Daichi Shimbo
Abstract
BACKGROUND: Home blood pressure (BP) monitoring over a 7-day period is recommended to confirm the diagnosis of hypertension. METHODS: We determined upper and lower home BP thresholds with >90% positive predictive value and >90% negative predictive value using 1 to 6 days of monitoring to identify high home BP (systolic BP ≥130 mm Hg or diastolic BP ≥80 mm Hg) based on 7 days of home BP monitoring. The sample included 361 adults from the Improving the Detection of Hypertension Study who were not taking antihypertensive medication. We used two 7-day periods, at least 3 days apart, the first being a sampling period and the second a reference period. For each number of days in the sampling period, we determined the percentage of participants who had a high likelihood of having (>90% positive predictive value) or not having (>90% negative predictive value) high BP and would not need to continue home BP monitoring. Only the participants in an uncertain category (ie, positive predictive value ≤90% and negative predictive value ≤90%) after each day were carried forward to the next day of home BP monitoring. RESULTS: Of the 361 participants (mean [SD] age of 41.3 [13.2] years; 60.4% women), 38.0% had high home BP during the reference period. There were 63.7%, 17.1%, 10.5%, 3.3%, 3.6%, and 1.4% participants who would not need to continue after 1, 2, 3, 4, 5, and 6 days of monitoring. CONCLUSIONS: In most people, high home BP can be identified or excluded with a high degree of confidence with 3 days or less of monitoring.