Short-Term Reproducibility of Masked Hypertension Among Adults Without Office Hypertension

Abstract

The 2017 American College of Cardiology/American Heart Association blood pressure (BP) Hypertension Clinical Practice Guidelines recommends ambulatory BP monitoring to detect masked hypertension. Data on the short-term reproducibility of masked hypertension are scarce. The IDH study (Improving the Detection of Hypertension) enrolled 408 adults not taking antihypertensive medication from 2011 to 2013. Office BP and 24-hour ambulatory BP monitoring were performed on 2 occasions, a median of 29 days apart. After excluding participants with office hypertension (mean systolic BP ≥130 mm Hg or diastolic BP ≥80 mm Hg), the analytical sample included 254 participants. Using the κ statistic, we evaluated the reproducibility of masked awake hypertension (awake systolic/diastolic BP ≥130/80 mm Hg) defined by the 2017 BP guideline thresholds, as well as masked 24-hour (24-hour systolic/diastolic BP ≥125/75 mm Hg), masked asleep (asleep systolic/diastolic BP ≥110/65 mm Hg), and any masked hypertension (high awake, 24-hour, and asleep BP). The mean (SD) age of participants was 38.0 (12.3) years and 65.7% were female. Based on the first and second ambulatory BP recordings, 24.0% and 26.4% of participants, respectively, had masked awake hypertension. The κ statistic (95% CI) was 0.50 (0.38-0.62) for masked awake, 0.57 (0.46-0.69) for masked 24-hour, 0.57 (0.47-0.68) for masked asleep, and 0.58 (0.47-0.68) for any masked hypertension. Clinicians should consider the moderate short-term reproducibility of masked hypertension when interpreting the results from a single ambulatory BP recording.

Keywords: American Heart Association; blood pressure monitoring; guideline; masked hypertension; statistics.

Figure 1.. Inclusion cascade for the analysis on the reproducibility of masked hypertension in the auscultatory office blood pressure sample

Legend: ABPM = ambulatory blood pressure monitoring; BP = blood pressure. Office BP was calculated as the mean of all office BP measurements. Complete office BP defined as ≥ 2 BP measurements at office visit 1 and office visit 2. Complete ABPM defined by International Database of Ambulatory Blood Pressure in Relation to Cardiovascular Outcome [IDACO] criteria: ≥10 daytime and ≥5 nighttime readings, at both ABPM 1 and ABPM 2.

Figure 2.. Prevalence of each type of masked hypertension for ABPM 1 and ABPM 2 in the auscultatory office blood pressure sample

Legend: ABPM = ambulatory blood pressure monitoring. Masked awake hypertension is defined as mean awake SBP ≥ 130 mm Hg and/or mean awake DBP ≥ 80 mm Hg; masked 24-hour hypertension as mean 24-hour SBP ≥ 125 mm Hg and/or mean 24-hour DBP ≥ 75 mm Hg; masked asleep hypertension as mean asleep SBP ≥ 110 mm Hg and/or mean asleep DBP ≥ 65 mm Hg; and any masked hypertension on ABPM is defined as having masked awake hypertension, masked 24-hour hypertension, and/or masked asleep hypertension.