Optimizing Precision of Hypertension Care to Maximize Blood Pressure Control: A Pilot Study Utilizing a Smartphone App to Incorporate Plasma Renin Activity Testing

Abstract

Only half of patients with hypertension (HTN) respond to any given antihypertensive medication. Heterogeneity in pathophysiologic pathways underlying HTN is a major contributor. Personalizing antihypertensive therapy could improve blood pressure (BP) reduction. The objective of this study was to assess the effect of pragmatic implementation of a personalized plasma renin activity (PRA)-based smartphone app on improving BP reduction. Patients with untreated or treated but uncontrolled HTN were recruited. BP and PRA were measured at baseline with final BP measured at 6 months. Patient's information was entered into the app and treatment recommendations were returned. Clinicians were at liberty to follow or disregard the app's recommendations. BP levels and percent BP control among patients whose clinicians did and did not follow the app's recommendations were compared using independent t-test and Fisher's exact test, respectively. Twenty-nine European American patients were included (38% women) with mean age of 52 ± 9 years and median PRA of 1.3 ng/mL/hr (interquartile range 0.5-3.1 ng/mL/hr). Participants whose clinicians followed the app's recommendations (n = 16, 55%) as compared with those whose clinicians did not (n = 13, 45%), had a greater reduction in 6-month systolic BP (-15 ± 21 vs. -3 ± 21 mm Hg; adjusted-P = 0.1) and diastolic BP (-8 ± 8 vs. -1 ± 8 mm Hg; adjusted-P = 0.04). BP control at 6 months tended to be greater among patients whose clinicians accepted the app's recommendations vs. those whose clinicians did not (63% vs. 23%, P = 0.06). This pilot study demonstrates that acceptance of the app's recommendations was associated with a greater BP reduction. Future studies to confirm these pilot findings are warranted.

Trial registration: ClinicalTrials.gov NCT02814552.

Figure 1

Example screenshots of the personalized PRA‐based smartphone app. Anti‐R, anti‐renin drugs including angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), β‐blockers, direct renin inhibitors and central α2‐agonists; Anti‐V, anti‐volume drugs including diuretics, aldosterone receptor antagonists, calcium channel blockers, vasodilators and α1‐blockers; BP, blood pressure; HTN, hypertension; PRA, plasma renin activity.

Figure 2

Each line represents a study participant. BP changes of participants whose clinicians accepted the app recommendations and those whose clinicians did not (a) SBP changes of participants whose clinicians accepted the app’s recommendations (n = 16) and those whose clinicians did not accept the app’s recommendations (n = 13). (b) DBP changes of participants whose clinicians accepted the app’s recommendations (n = 16) and those whose clinicians did not accept the app’s recommendations (n = 13). BP, blood pressure; DBP, diastolic blood pressure; SBP, systolic blood pressure.

Figure 3

Adjusted BP changes of participants whose clinicians accepted the app recommendations vs those whose clinicians did not (a) Adjusted SBP changes (mean with SD) of participants whose treatment recommendations provided by the app were accepted (n = 16; −15 ± 21 mmHg) vs. those whose treatment recommendations provided by the app were not accepted (n = 13; −3 ± 21 mmHg; adjusted‐P = 0.1). (b) Adjusted DBP changes (mean with SD) of participants whose treatment recommendations provided by the app were accepted (n = 16; −8 ± 8.4 mmHg) vs. those whose treatment recommendations provided by the app were not accepted (n = 13; −1 ± 8 mmHg; adjusted‐P = 0.04). All values were adjusted for baseline SBP/DBP. BP, blood pressure; DBP, diastolic blood pressure; SBP, systolic blood pressure.