Background: The development of automated, smartphone application (app)-assisted home blood pressure monitoring (HBPM) allows for standardized measurement of blood pressure (BP) at home. The aim of this study was to evaluate the (diagnostic) agreement between app-assisted HBPM, automated office BP (OBP), and the reference standard 24-hour ambulatory BP monitoring (ABPM).
Methods: In this open randomized 5-way cross-over study, patients diagnosed with hypertension were randomized to one of 10 clusters, each containing 5 BP measurement methods (ABPM, HBPM, attended OBP, unattended OBP, and unattended 30-minute BP) in different order.
Results: In total, 113 patients were included. The average 24-hour ABPM was 126±11/73±8 mm Hg compared with 141±14/82±10 mm Hg with app-assisted HBPM, 134±13/80±9 mm Hg with unattended 30-minute BP, 137±16/81±11 mm Hg with attended OBP, and 135±15/81±10 mm Hg with unattended OBP monitoring. Diagnostic agreement between app-assisted HBPM and 24-hour ABPM for diagnosing sustained (OBP >140/90 mm Hg and ABPM ≥130/80 mm Hg or HBPM ≥135/85 mm Hg), white-coat (OBP ≥140/90 mm Hg and ABPM <130/80 mm Hg or HBPM <135/85 mm Hg), and masked hypertension (OBP <140/90 mm Hg and ABPM ≥130/80 mm Hg or HBPM ≥135/85 mm Hg) was fair-to-moderate (κ statistics ranging from 0.34 to 0.40). App-assisted HBPM had high sensitivities (78%-91%) and negative predictive values (90%-97%) for diagnosing sustained and masked hypertension.
Conclusions: This study showed a considerable (diagnostic) disagreement between app-assisted HBPM and ABPM. App-assisted HBPM had high sensitivity in the diagnosis of sustained and masked hypertension and may therefore be used as complementary to, but not a replacement of, ABPM.
Keywords: ambulatory blood pressure monitoring; blood pressure; home blood pressure monitoring; hypertension; masked hypertension; white-coat hypertension.