Pharmacogenomic Evaluation of Antihypertensive Responses

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: NCT00246519
Recruitment Status : Completed
First Posted : October 31, 2005
Results First Posted : July 10, 2013
Last Update Posted : May 7, 2018
Information provided by (Responsible Party):
University of Florida

Study Type: Interventional
Study Design: Allocation: Randomized;   Intervention Model: Crossover Assignment;   Masking: None (Open Label);   Primary Purpose: Treatment
Condition: Hypertension
Interventions: Drug: Hydrochlorothiazide
Drug: Atenolol

  Participant Flow

Recruitment Details
Key information relevant to the recruitment process for the overall study, such as dates of the recruitment period and locations
Subjects were recruited to 3 sites, the University of Florida, Mayo Clinic in Rochester Minnesota, and Emory University. Subjects were seen in medical clinics by physicians and/or nurse coordinators. Patients were recruited from 2005-2010.

Pre-Assignment Details
Significant events and approaches for the overall study following participant enrollment, but prior to group assignment
After enrollment subjects were currently on medication for blood pressure were required to wash out for a minimum of 2-4 weeks, at which point the blood pressure was reassessed for eligibility into the study. Of the 1701 subjects who enrolled in the study, 888 subjects met eligibility requirements to continue the study while 813 subjects did not.

Reporting Groups
Atenolol + Hydroclorothiazide (HCTZ) Arm atenolol 50 mg, then 100 mg if BP < 120/70, then add HCTZ 12.5 mg if BP < 120/70, then HCTZ 25 mg if BP < 120/70
Hydrochlorothiazide (HCTZ) + Atenolol HCTZ 12.5 mg then HCTZ 25 mg if BP < 120/70, then add atenolol 50 mg if BP < 120/70, then atenolol 100 mg if BP < 120/70.

Participant Flow:   Overall Study
    Atenolol + Hydroclorothiazide (HCTZ) Arm   Hydrochlorothiazide (HCTZ) + Atenolol
STARTED   442   446 
COMPLETED   386   382 
NOT COMPLETED   56   64 

  Baseline Characteristics

Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
No text entered.

Reporting Groups
Atenolol +HCTZ Arm atenolol 50 mg, then 100 mg if BP < 120/70, then add HCTZ 12.5 mg if BP < 120/70, then HCTZ 25 mg if BP < 120/70
HCTZ + Atenolol HCTZ 12.5 mg then HCTZ 25 mg if BP < 120/70, then add atenolol 50 mg if BP < 120/70, then atenolol 100 mg if BP < 120/70.
Total Total of all reporting groups

Baseline Measures
   Atenolol +HCTZ Arm   HCTZ + Atenolol   Total 
Overall Participants Analyzed 
[Units: Participants]
 442   446   888 
[Units: Participants]
Count of Participants
<=18 years      1   0.2%      0   0.0%      1   0.1% 
Between 18 and 65 years      437  98.9%      440  98.7%      877  98.8% 
>=65 years      4   0.9%      6   1.3%      10   1.1% 
[Units: Years]
Mean (Standard Deviation)
 48.4  (9.3)   48.8  (9.2)   48.6  (9.3) 
Sex: Female, Male 
[Units: Participants]
Count of Participants
Female      251  56.8%      223  50.0%      474  53.4% 
Male      191  43.2%      223  50.0%      414  46.6% 
Region of Enrollment 
[Units: Participants]
United States   442   446   888 

  Outcome Measures

1.  Primary:   Blood Pressure Response (Delta BP (After 18 Weeks of Medication - Baseline)).   [ Time Frame: baseline to 18 weeks of treatment ]

2.  Secondary:   Adverse Metabolic Responses   [ Time Frame: 9-18 weeks of treatment ]
Results not yet reported.   Anticipated Reporting Date:   No text entered.  

  Serious Adverse Events

  Other Adverse Events

  Limitations and Caveats

Limitations of the study, such as early termination leading to small numbers of participants analyzed and technical problems with measurement leading to unreliable or uninterpretable data
The trial has limited number of hypertensive patients of African ancestry, therefore power is limited to those patients.

  More Information

Certain Agreements:  
Principal Investigators are NOT employed by the organization sponsoring the study.
There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.

Results Point of Contact:  
Name/Title: Julie A. Johnson
Organization: University of Florida
phone: 352-273-6007

Publications of Results:

Publications automatically indexed to this study by Identifier (NCT Number):

Responsible Party: University of Florida Identifier: NCT00246519     History of Changes
Other Study ID Numbers: U01GM074492 ( U.S. NIH Grant/Contract )
First Submitted: October 27, 2005
First Posted: October 31, 2005
Results First Submitted: May 20, 2013
Results First Posted: July 10, 2013
Last Update Posted: May 7, 2018