Ambulatory Blood Pressure Monitoring (ABPM) as THE reference standard to confirm diagnosis of hypertension in adults: Recommendation of the 2015 U.S. Preventive Services Task Force (USPSTF)

Previous publications by committees of the USPSTF (Sheridan et al., 2003; USPSTF, 2007) ratified the importance of routine office blood pressure (BP) monitoring (OBPM) to screen adults 18 years of age for hypertension and when substantiated management by lifestyle changes and BP-lowering medications to attenuate incidence of cardiovascular disease (CVD) events. The 2015 USPSTF report (Piper et al., 2015) constitutes an important update that recommends significant changes in primary care practice guided by answers to several key questions, mainly (i) Does screening for high BP reduce CVD events in adults 18 years of age? (ii) What is the best way to screen for elevated BP in adults in the primary care setting? (iii) What is the best way to confirm hypertension in adults who by OBPM initially screen positive for high BP? From our perspective, the most important conclusions of the thorough and excellent 2015 USPSTF report (Piper et al., 2015) are (i) ABPM compared with OBPM, even when bolstered with home blood pressure monitoring (HBPM), better predicts risk of future CVD events – nonfatal and fatal myocardial infarct, sudden cardiac death, stroke, heart failure, atrial fibrillation, and (ii) ABPM, rather than traditional and long-honored OBPM, now be considered the reference standard in primary care medicine to diagnose hypertension in adults 18 years of age, i.e., corroborate or contradict OBPMdetermined elevated BP based on single or repeatedinterval in-office measurements, to preclude misdiagnosis and associated unwarranted clinical management, including institution of unnecessary costly therapy with potential risk of adverse effects. These conclusions are founded on analyses of data of 11 quality studies that demonstrate ABPM predicts long-term CVD outcomes independently of OBPM, with hazard ratio (HR) ranging from 1.28 to 1.40, plus documentation of great variation, between 35 and 95%, in confirming hypertension as the definitive diagnosis among 27 studies in which OBPM screenings were followed-up by a non-office, i.e., ABPM or HBPM, assessment method (Piper et al., 2015). The 2015 report, as expected (Hermida et al., 2012, 2013g), also verified incidence of CVD events in those displaying elevated BP by initial OBPM screening yet proven normotensive by ABPM or HBPM follow-up, i.e., commonly termed isolated office hypertension but the more accurate term preferred by us is masked normotension (MN) (Hermida et al., 2013h), is comparable to that of true normotensive persons (Hermida et al., 2012; Piper et al., 2015). Critical questions relating to the exact nature of the diagnostic ABPM protocol, i.e., application of ABPM during the hours of activity only, full 24 h, or two consecutive 24 h spans (48 h); derived endpoint(s), i.e., daytime vs. nighttime (preferably sleep-time), vs. 24 h mean systolic BP (SBP) or diastolic BP (DBP), to achieve accurate diagnosis (Hermida et al., 2013c); and respective time-span specific threshold criteria for SBP and DBP means to differentiate normotension from hypertension, currently 135/85, 120/70, and 130/80 mmHg (Hermida et al., 2013d, 2013h), and necessity of