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Genetic Epidemiology of Responses to Antihypertensives (GERA)

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT00005520
First Posted: May 26, 2000
Last Update Posted: January 17, 2013
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.
Collaborator:
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
Stephen T. Turner, Mayo Clinic
  Purpose
To determine whether measured variation in genes coding for components of vasoconstriction and volume regulating systems predict interindividual differences in blood pressure response to therapy with a thiazide diuretic, hydrochlorothiazide, or an angiotensin II receptor blocker, candesartan, in hypertensive African-Americans (N=300 treated with each drug) and in hypertensive European Americans (N=300 treated with each drug).

Condition Intervention
Cardiovascular Diseases Heart Diseases Hypertension Drug: Hydrochlorothiazide Drug: Candesartan

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Genetic Epidemiology of Responses to Antihypertensives

Resource links provided by NLM:


Further study details as provided by Stephen T. Turner, Mayo Clinic:

Primary Outcome Measures:
  • Change in blood pressure [ Time Frame: 4 weeks for hydrochlorothiazide; 6 weeks for candesartan ]
    The blood pressure response to antihypertensive drug therapy was defined by the difference between blood pressure levels prior to and at the end of drug therapy.


Secondary Outcome Measures:
  • Adverse metabolic changes [ Time Frame: 4 weeks for hydrochlorothiazide only ]
    Potentially adverse metabolic changes in response to hydrochlorothiazide include changes in fasting serum glucose and insulin; serum potassium; serum lipids (triglycerides, HDL-cholesterol, total cholesterol); and serum uric acid.


Biospecimen Retention:   Samples With DNA
Serum, plasma, buffy coat, urine.

Enrollment: 1200
Study Start Date: February 1997
Study Completion Date: January 2008
Primary Completion Date: January 2008 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
African American hydrochlorothiazide
300 African American hypertensives were treated with hydrochlorothiazide 25 mg daily for 4 weeks.
Drug: Hydrochlorothiazide
European American hydrochlorothiazide
300 European American hypertensives were treated with hydrochlorothiazide 25 mg daily for 4 weeks
Drug: Hydrochlorothiazide
African American candesartan
300 African American hypertensives were treated with candesartan 16 mg daily for 2 weeks followed by 32 mg daily for 4 weeks
Drug: Candesartan
European American candesartan
300 European American hypertensives were treated with candesartan 16 mg daily for 2 weeks followed by 32 mg daily for 4 weeks
Drug: Candesartan

Detailed Description:

BACKGROUND:

Essential hypertension is a common disorder that contributes to morbidity, mortality, and cost of health care, especially among African-Americans. Although a single-drug therapy is commonly prescribed for treatment of hypertension, blood pressure levels are controlled in some individuals but not in others. The study has the potential to identify genes contributing to the etiology of interindividual differences in blood pressure response to diuretic therapy in African-Americans and European Americans.

DESIGN NARRATIVE:

Hypertensive adults were treated with the diuretic hydrochlorothiazide, 25 mg/day, for four weeks; or with the angiotensin II receptor blocker candesartan, 16 mg/day for 2 weeks followed by 32 mg/day for 4 weeks. Interindividual variations in blood pressure responses and in candidate genes coding for components of systems regulating vasoconstriction and volume were measured. In addition, a panel of 500,000 single nucleotide polymorphisms genome-wide was measured in subsets of the most extreme responders and nonresponders to each drug for genome-wide association of analyses.

  Eligibility

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Adult African American men and women with previously diagnosed primary hypertension were recruited from Atlanta, Georgia; and adult European American man and women with previously diagnosed primary hypertension were recruited from Rochester, Minnesota.
Criteria
Primary (essential) hypertension
  Contacts and Locations
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 ClinicalTrials.gov identifier (NCT number): NCT00005520


Locations
United States, Minnesota
Mayo Clinic
Rochester, Minnesota, United States
Sponsors and Collaborators
Mayo Clinic
National Heart, Lung, and Blood Institute (NHLBI)
Investigators
Principal Investigator: Stephen T. Turner, M.D. Mayo Foundation
  More Information

Publications:

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Stephen T. Turner, Professor of Medicine, Mayo Clinic
ClinicalTrials.gov Identifier: NCT00005520     History of Changes
Other Study ID Numbers: 05-004017
R01HL053330 ( U.S. NIH Grant/Contract )
R01HL074735 ( U.S. NIH Grant/Contract )
First Submitted: May 25, 2000
First Posted: May 26, 2000
Last Update Posted: January 17, 2013
Last Verified: January 2013

Keywords provided by Stephen T. Turner, Mayo Clinic:
Hypertension
Pharmacogenetics
Hydrochlorothiazide
Candesartan

Additional relevant MeSH terms:
Hypertension
Cardiovascular Diseases
Heart Diseases
Vascular Diseases
Candesartan
Candesartan cilexetil
Hydrochlorothiazide
Antihypertensive Agents
Diuretics
Natriuretic Agents
Physiological Effects of Drugs
Sodium Chloride Symporter Inhibitors
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Angiotensin II Type 1 Receptor Blockers
Angiotensin Receptor Antagonists