We're building a better ClinicalTrials.gov. Check it out and tell us what you think!
ClinicalTrials.gov Menu

Genetics of Hypertension Associated Treatments (GenHAT) (GenHAT)

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.
ClinicalTrials.gov Identifier: NCT00006294
Recruitment Status : Completed
First Posted : September 26, 2000
Last Update Posted : April 6, 2018
University of Minnesota
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
Donna Arnett, 257-5678, University of Kentucky

Brief Summary:
To examine whether the association between selected hypertensive genes and combined fatal coronary heart disease and nonfatal myocardial infarction in high-risk hypertensives is modified by the type of antihypertensive treatment, leading to differential risks of coronary heart disease.

Condition or disease Intervention/treatment
Cardiovascular Diseases Heart Diseases Hypertension Coronary Disease Myocardial Infarction Drug: Chlorthalidone Drug: Lisinopril Drug: Amlodipine Drug: Doxazosin

Detailed Description:


The study might shed important light on the variation in patient response to antihypertensive agents, and improve the ability to pick the right antihypertensive for specific patients. GenHAT is an ancillary study to ALLHAT (the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial). ALLHAT recruited 42,515 hypertensives and randomized them to one of four antihypertensive agents (lisinopril, chlorthalidone, amlodipine, and doxazosin); follow-up will be completed in March, 2002.


GenHAT, a prospective study ancillary to ALLHAT, will characterize hypertension genetic variants and determine their interaction with antihypertensive treatments in relation to coronary heart disease (CHD). DNA from frozen clots stored at the ALLHAT Central Laboratory will be used to genotype variants of hypertension genes (angiotensinogen -6, angiotensin converting enzyme insertion/deletion, angiotensin type- 1 receptor, alpha-adducin, beta2 adrenergic receptor, lipoprotein lipase, and 10 new hypertension variants expected to be discovered during the course of the study). In addition to the primary aim, a number of secondary aims will be undertaken to evaluate gene- treatment interactions in relation to other endpoints, including all-cause mortality, stroke, heart failure, left ventricular hypertrophy, decreased renal function, peripheral arterial disease, and blood pressure lowering. Because of the ethnic and gender diversity of ALLHAT, an assessment will be made of the effects of these variants on outcomes in key subgroups (age >65 years, women, African Americans, Type II diabetics), and whether the gene-treatment interactions in relation to outcomes are consistent across subgroups.

Layout table for study information
Study Type : Observational
Actual Enrollment : 37939 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Pharmacological Association of the Angiotensin-Converting Enzyme Insertion/Deletion Polymorphism on Blood Pressure and Cardiovascular Risk in Relation to Anti-hypertensive Treatment
Study Start Date : September 1999
Actual Primary Completion Date : August 2005
Actual Study Completion Date : August 2005

Resource links provided by the National Library of Medicine

Group/Cohort Intervention/treatment
Participants will take chlorthalidone at recommended doses to control hypertension
Drug: Chlorthalidone
participant's drug dose will be titrated from 12.5mg to 25mg over the course of the study
Other Name: Hygroton, Thalitone, Chlorthalid

Participants will take Amlodipine at recommended doses to control hypertension
Drug: Amlodipine
participant's drug dose will be titrated from 10mg to 40mg over the course of the study
Other Name: Norvasc

Participants will take Lisinopril at recommended doses to control hypertension
Drug: Lisinopril
participant's drug dose will be titrated from 10mg to 40mg over the course of the study
Other Name: Zestoretic

Participants will take Doxazosin at recommended doses to control hypertension
Drug: Doxazosin
participant's drug dose will be titrated from 2mg to 8mg over the course of the study
Other Name: Cardura

Primary Outcome Measures :
  1. Blood Pressure [ Time Frame: baseline and six month ]
    Blood pressure will be measured to determine the effect of the prescribed anti-hypertensive . Data will be presented as the change in blood pressure over the course of six months

Secondary Outcome Measures :
  1. Effect of genotype on event rates [ Time Frame: 6 years ]
    The rate of fatal myocardial infarction (MI) was evaluated in relation to the ACE I/D genotype and anti-hypertensive used. Data are presented as the incidence of fatal MI after six years of follow up

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   55 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Hypertensive individuals, multiple races and ethnic groups are represented in this study population
  • not taking anti-hypertensive medication
  • use of anti-hypertensives for less than two months with a baseline blood pressure between 140/90 and 180/110
  • use of anti-hypertensives for greater than two months with a blood pressure not greater than 160/100
  • at least one additional cardiovascular risk factor such as previous MI, stroke, type 2 diabetes, smoking, left ventricular hypertrophy or dyslipidemia

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): NCT00006294

Layout table for location information
United States, Kentucky
University of Kentucky
Lexington, Kentucky, United States, 40536
Sponsors and Collaborators
Donna Arnett, 257-5678
University of Minnesota
National Heart, Lung, and Blood Institute (NHLBI)
Layout table for investigator information
Principal Investigator: Donna Arnett University of Kentucky
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Layout table for additonal information
Responsible Party: Donna Arnett, 257-5678, PI, University of Kentucky
ClinicalTrials.gov Identifier: NCT00006294    
Other Study ID Numbers: 911
R01HL063082 ( U.S. NIH Grant/Contract )
First Posted: September 26, 2000    Key Record Dates
Last Update Posted: April 6, 2018
Last Verified: April 2018

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Additional relevant MeSH terms:
Layout table for MeSH terms
Cardiovascular Diseases
Myocardial Infarction
Heart Diseases
Coronary Disease
Vascular Diseases
Pathologic Processes
Myocardial Ischemia
Antihypertensive Agents
Calcium Channel Blockers
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Calcium-Regulating Hormones and Agents
Physiological Effects of Drugs
Vasodilator Agents
Angiotensin-Converting Enzyme Inhibitors
Protease Inhibitors
Enzyme Inhibitors
Cardiotonic Agents
Protective Agents
Natriuretic Agents
Sodium Chloride Symporter Inhibitors