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VA CSP Study No. 597: Diuretic Comparison Project

| Diuretic Comparison Project Home Page | Information for Veterans | Information for VA Providers | Study Team and Contact Information |


DCP is a national, voluntary research study funded by the VA Cooperative Studies Program (CSP), with the Department of Veterans Affairs Office of Research and Development. The goal of the DCP study is to compare the benefits of two commonly used medications, using an innovative study design. DCP uses Point of Care (POC) methodology, which embeds as much of the study procedures as possible into the routine medical care of Veterans. The result is a streamlined and efficient trial that follows clinical practice, thereby enhancing the ability to learn the answers to important questions directly within the VA healthcare system, thus supporting the goal for VA to be a Learning Healthcare System.

In this study, we will compare the effectiveness of two common diuretics, hydrochlorothiazide and chlorthalidone, on reducing the risk of cardiovascular events among Veterans over the age of 65 years who are currently taking hydrochlorothiazide to treat their hypertension. Both of these medications are FDA approved and have been used to treat high blood pressure for more than 50 years. Although hydrochlorothiazide is more commonly used, some evidence suggests that chlorthalidone may be more effective at preventing heart attacks and strokes. The DCP will be the first large-scale research study that uses the POC study design for a direct comparison between hydrochlorothiazide and chlorthalidone. By leveraging the VA's electronic medical record (EMR) system, DCP plans to enroll 13,500 veterans and record heart attacks, strokes, and other cardiovascular events while each VA healthcare provider continues to treat their patients as usual. No additional study visits are needed.

The DCP is chaired by Dr. Areef Ishani of the Minneapolis VA Medical Center and Dr. William Cushman of the Memphis VA Medical Center. Dr. Ishani is a Professor of Medicine at the University of Minnesota where he received the Department of Medicine Outstanding Educator Award in 2014. Dr. Ishani is Director of Primary Care and Specialty Medicine at the Minneapolis VA. Dr. Ishani's academic activity has focused on acute kidney injury.

Dr. William Cushman is Chief of the Preventive Medicine Section at the Veterans Affairs Medical Center in Memphis, Tennessee, Professor of Preventive Medicine, Medicine, and Physiology at the University of Tennessee Health Science Center, and the Lead Hypertension Consultant to Medical Service in Central Office of the Department of Veterans Affairs. He has been an investigator in many clinical studies relating to hypertension, diabetes, and lipid therapy. In 2005, Dr. Cushman received the Excellence in Leadership Award, Consortium for Southeastern Hypertension Control (COSEHC), and in 2010 he received the John Blair Barnwell Award for outstanding achievement in clinical science, the Department of Veterans Affairs Clinical Science Research and Development's highest honor for scientific achievement. Dr. Cushman is also a Principle Investigator in the Systolic Blood Pressure Intervention Trial (SPRINT) examining the intensive lowering of systolic blood pressure on preventing cardiovascular disease in older patients.

The DCP is being conducted out of the Boston CSP Coordinating Center (VA Cooperative Studies Program). The DCP protocol has been reviewed and approved by VA Central Institutional Review Board (IRB), Cooperative Studies Scientific Evaluation Committee (CSSEC), and the Research Offices at VA Boston Healthcare System, Minneapolis VA Health Care System, Memphis VA Medical Center, and Canandaigua VA Medical Center.

This study represents an important step in VHA's efforts to enable a Learning Healthcare System, and is made possible by partnerships with a wide range of VA offices and personnel, including:

  • Patient Care Services
  • Pharmacy Benefits Management
  • Office of Information & Technology
  • The National Center for Ethics in Health Care


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Any health information on this website is strictly for informational purposes and is not intended as medical advice. It should not be used to diagnose or treat any condition.