Diagnostic accuracy of manual office blood pressure measurement in ambulatory hypertensive patients in Korea

Background/Aims: Currently, office blood pressure (OBP) is the most widely used method of measuring blood pressure (BP) in daily clinical practice. However, data on the diagnostic accuracy of OBP in reference to ambulatory blood pressure (ABP) are scarce in Korea. Methods: In retrospective and prospective cohorts, manual OBP and ABP measurements were compared among ambulatory hypertensive patients. Hypertension was defined as systolic OBP 140 mmHg and/or diastolic OBP 90 mmHg, and systolic ABP 130 mmHg and/or diastolic ABP 80 mmHg. Results: In the retrospective cohort (n = 903), the mean OBP1 (before ABP measurement) was higher than ABP in both systolic (138 17 mmHg vs. 123 13 mmHg, p < 0.001) and diastolic (84 12 mmHg vs. 78 11 mmHg, p < 0.001) measurements. Interestingly, there was only a weak correlation between OBP and ABP (r 2 = 0.038, p < 0.001). The overall discordance rate of OBP compared to ABP, which is the reference method for measuring BP, was 43.9%. The prospective cohort (n = 57) showed similar results. In a subgroup analysis, male patients had higher false negative results (masked or under-treated hypertension) than did female patients (26.1% vs. 17.8%, p = 0.003), whereas female patients had a higher false positive rate (white-coat or over-treated hypertension) than did male patients (28.7% vs. 15.2%, p < 0.001).