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Physician Uncertainty Reduction for Hypertension

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00201084
Recruitment Status : Completed
First Posted : September 20, 2005
Last Update Posted : July 21, 2014
National Heart, Lung, and Blood Institute (NHLBI)
The University of Texas Health Science Center, Houston
Kelsey Research Foundation
Information provided by (Responsible Party):
David Hyman, Baylor College of Medicine

Brief Summary:
The purpose of this study is to test the theory that a major factor in poor blood pressure (BP) control is that physicians fail to intensify antihypertensive therapy for their patients.

Condition or disease Intervention/treatment Phase
Cardiovascular Diseases Heart Diseases Hypertension Behavioral: Uncertainty reduction Not Applicable

Detailed Description:


A large amount of literature suggests that the majority of "uncontrolled" hypertensives are under medical care, and that lack of control is largely explained by physicians not intensifying treatment to achieve the BP targets recommended in the national guidelines. Traditional physician education, feedback, and reminders have a limited effect in promoting a rapid rate of guideline implementation. The theoretical framework of diffusion of innovations suggests that providing physicians with tools to reduce uncertainty about the attributes of a guideline may accelerate the adoption process. The presumed barriers to treatment intensification for uncontrolled hypertension are: 1) uncertainty over the patient's "true" BP; 2) uncertainty over whether the patient is adherent to medications already prescribed; and 3) uncertainty over the benefits of adding medications when patients express preference for lifestyle modification.


This cluster randomized trial in 10 primary care clinics (5 intervention and 5 control) will test the hypothesis that an intervention based on diffusion of innovations theory, and targeting provider treatment actions, will increase the prevalence of BP control to Joint National Committee-7(JNC-7) recommended levels in African American patients (greater than 140/90 mm Hg or greater 130/80 mm Hg if the patient has diabetes). The uncertainty reduction tools in the "Uncertainty Reduction to Accelerate Diffusion (URAD)" practices will include: 24-hour ambulatory BP monitoring, electronic bottle-cap monitoring of medication adherence, and medication and lifestyle counseling. The "Usual Practice (UP)" physicians will receive education about the guidelines and a "placebo" chart form indicating the patient is being followed in a BP control study. The 10 participating clinics represent a large, multi-site private group practice and a public health care system. Sixty-seven patients per clinic (670 total) will be enrolled when the intervention is initiated, and their BP and self-reported medication and lifestyle adherence will be monitored for two years. Sixty percent of the sample will be African American, and the study will have 90% power to detect a difference of 20% in the prevalence of hypertension control in the African Americans as a result of the intervention (50% control in URAD clinics vs. 30% control UP clinics). Secondary endpoints will include BP measurements by study staff under standardized conditions, physician treatment intensification actions, patient adherence, characteristics of doctor-patient communication associated with treatment action, use of the URAD components, and physician knowledge and beliefs about the JNC 7 guidelines and their relationship to BP control. Analysis of secondary endpoints will include race. The research team has collaborated with both health systems in previous studies, and is experienced in conducting hypertension control and behavioral intervention studies in the target population.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 670 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Physician Uncertainty Reduction for Hypertension
Study Start Date : September 2004
Actual Primary Completion Date : July 2009
Actual Study Completion Date : July 2009

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Active Comparator: 1
Uncertainty reduction tools, at physician discretion, 24 hour ambulatory BP monitoring and/or electronic bottle cap monitoring and/or lifestyle counseling
Behavioral: Uncertainty reduction
At physician discretion, 24 hour ambulatory BP monitoring and/or electronic bottle cap monitoring and/or lifestyle counseling

No Intervention: 2
Usual primary care

Primary Outcome Measures :
  1. Expressed as the proportion of patients with average clinic BP less than 140/90 mm Hg in the previous two visits (130/80 mm Hg if the patient also has diabetes) [ Time Frame: 24 months ]

Secondary Outcome Measures :
  1. Actual measure clinic systolic and diastolic BP, patient physician communication patterns [ Time Frame: 24 months ]
  2. Patient adherence to medication and healthy lifestyle [ Time Frame: 24 months ]
  3. Physician knowledge, attitude, and beliefs about JNC-7 goals and barriers to achievement of the treatment goals and cost [ Time Frame: 24 months ]

Information from the National Library of Medicine

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Ages Eligible for Study:   Child, Adult, Older Adult
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Kept appointment on index visit day (see patient sampling and recruitment methods below)
  • Had one previous visit to the setting within the past year and identified the setting as his/her usual source of care
  • Average clinic BP on index visit and one most recent previous visit was equal to or greater than 140 mm Hg systolic or 90 mm Hg diastolic (130/80 mm Hg if diabetic)
  • Acknowledges understanding of the study goals and methods and gives informed consent to participate in study measurements and other procedures

Exclusion Criteria:

  • Cognitive or other functional impairment sufficient to limit patient's ability to give informed consent, keep follow-up appointments, and participate actively in adherence to his or her treatment regimen
  • Renal insufficiencies or renal failure based on a recent serum creatinine greater than 2.0 or chart diagnosis
  • Planning to leave the Houston area within the next two years
  • Severe, life-threatening illness that makes hypertension treatment a secondary priority

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00201084

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United States, Texas
Baylor College of Medicine
Houston, Texas, United States, 77098
Sponsors and Collaborators
Baylor College of Medicine
National Heart, Lung, and Blood Institute (NHLBI)
The University of Texas Health Science Center, Houston
Kelsey Research Foundation
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Principal Investigator: David J. Hyman, MD Baylor College of Medicine
Publications of Results:
Other Publications:
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Responsible Party: David Hyman, Professor, Baylor College of Medicine Identifier: NCT00201084    
Other Study ID Numbers: 276
R01HL078589 ( U.S. NIH Grant/Contract )
First Posted: September 20, 2005    Key Record Dates
Last Update Posted: July 21, 2014
Last Verified: July 2014
Additional relevant MeSH terms:
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Cardiovascular Diseases
Heart Diseases
Vascular Diseases