Abstract 19898: Heightened Sympathetic Activity Related to Masked Uncontrolled Hypertension in Treated Hypertensive Patients
Introduction: Masked uncontrolled hypertension in treated hypertensive patients (MUCH) is defined as controlled blood pressure (BP) in clinic (BP < 140/90 mmHg) but uncontrolled BP out-of-clinic as measured by 24-hr ambulatory blood pressure monitoring (ABPM, daytime readings ≥ 135/85 mmHg).
Methods: In this prospective evaluation, hypertensive patients controlled on medications were recruited from the University of Alabama at Birmingham hypertension clinic. The patients were recruited after having consistently controlled BP readings at 3 or more clinic visits. All the patients were evaluated by clinic BP with use of the BpTRU device, home ABPM, 24-hr urine collection for measurement of catecholamines and metanephrines, and measurement of plasma free normetanephrines and metanephrines collected while in clinic. Eighty-nine patients were evaluated. Of these, 36 (40%) were controlled in clinic (BpTRU) and by daytime ABPM, indicating true controlled patients. The remaining 53 (60%) were controlled in clinic (BpTRU) but uncontrolled by daytime ABPM, consistent with MUCH.
Results: Based on out-of-clinic 24-hr urine collections, the patients identified as MUCH had significantly higher levels of urinary excretion of normetaneprhines, norepinephrine, dopamine, total metanephrines and total catecholamines compared to true controlled patients. The two groups did not differ in plasma free normetanephrines and metanephrines collected in clinic.
Conclusions: Patients with MUCH on daytime ABPM have heightened sympathetic activity compared to true controlled hypertensive patients. However, there is no difference in sympathetic activity between the two groups based on plasma samples collected in clinic. These findings suggest that patients with MUCH likely have higher out-of-clinic sympathetic activity contributing to their uncontrolled BP out-of-clinic. If so, they may preferentially benefit from medications that reduce sympathetic activity.
Author Disclosures: M. Siddiqui: None. H. Bhatt: None. E.K. Judd: None. T. Dudenbostel: None. S. Oparil: None. D.A. Calhoun: None.
- © 2016 by American Heart Association, Inc.