The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial  - (ALLHAT) 
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ALLHAT was the largest antihypertensive trial and the second largest lipid-lowering trial and included large numbers of patients over age 65, women, African-Americans, and patients with diabetes, treated largely in community practice settings.

A total of 42,418 patients were enrolled between February 23, 1994 and January 31, 1998. A vanguard phase was conducted in the first half of 1994; the full-scale trial began in the fall of 1994 and continued for eight years, until March 31, 2002. The last participant visit was March 31, 2002. The results of the trial were released December 17, 2002.

ALLHAT continues to analyze data for presentations and publications on secondary outcomes, outcomes in subgroups, and other topics for both the antihypertensive component and the lipid-lowering component of the trial. There is also an ongoing Dissemination effort to reach physicians, patients, and formulary benefits managers with the core messages of ALLHAT and the Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7).

Post-Trial Follow-up of ALLHAT Participants

Active follow-up of ALLHAT participants ended on March 31, 2002 (February 15, 2000 for doxazosin participants), for an average follow-up of 4.9 years (3.2 years for doxazosin). To answer additional scientific questions, a post-trial follow-up of participants through 2006 is planned to obtain data on post-trial morbidity and mortality. The extended follow-up will be carried out passively using national databases available through the National Death Index (NDI), Social Security Administration (SSA), Centers for Medicare and Medicaid Services (CMS), Department of Veterans Affairs (DVA), and United States Renal Data System (USRDS). When completed, endpoint data will be available for between 9 and 10 years of total follow-up.

The overall research objective of this extended follow-up is to compare long-term effects of antihypertensive treatment with a thiazide-type diuretic, a CCB, an ACE-inhibitor, or an a-receptor blocker when each drug is used as initial treatment with step-up drugs added as needed and, for the lipid component, to assess long-term effects of pravastatin compared with usual care. To meet these objectives, we will evaluate whether new differences emerge for outcomes that were not statistically different, especially CVD and total mortality, and whether the differences observed during the trial continue.

The ALLHAT extension protocol was developed by the CTC and the NHLBI Project Office and approved by the ALLHAT Steering Committee.

Phase III ALLHAT Outreach

In the past, ALLHAT data were available only to ALLHAT investigators. We are now making this resource available to the wider scientific community. We are encouraging new research to use the valuable resources collected by ALLHAT since the study began in 1994. We are especially interested in new investigators, including those early in their research careers. More specifically, a new investigator is one who

  • Is interested in using ALLHAT data for the first time
  • May be seeking funding for the first time, or may already have funding
  • May be affiliated either with an institution never before associated with ALLHAT, or an institution that has participated in ALLHAT in the past.

The ALLHAT Coordinating Center is dedicated to helping you obtain and use ALLHAT data for new investigations and publications. See Types Of Data Available and Unique Strengths Of ALLHAT for more information. See How You Can Use ALLHAT Data and How You Can Obtain ALLHAT Data for a description of how to acquire and use ALLHAT data.

For information about relevant National Heart, Lung, and Blood Institute opportunities, please see:

Please contact Kara Elam, ALLHAT Assistant Project Manager, if you need additional information or further assistance.

Coordinating Center for Clinical Trials
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