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Weight Loss Clinical Trials

The Longitudinal Assessment of Bariatric Surgery (LABS) is a two-phase study analyzing the risks and benefits of bariatric surgery and its impact on the health and well-being of patients with morbid obesity.

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Overview of Bariatric Clinical Trials

  • LABS is one of the first National Institutes of Health studies with a focus on bariatric surgery.
  • The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) initiated the LABS study in 2003.
  • Comprised of two phases — LABS-1 and LABS-2 — the study involves several thousand participants.
  • LABS-2 is one of the largest active cohorts of bariatric surgical patients being followed, long-term, in a research study.
  • A corollary study — Teen LABS — is for adolescents who have bariatric surgery.

Who’s involved

Experts in:

  • Bariatric surgery
  • Obesity research
  • Internal medicine
  • Endocrinology
  • Behavioral science
  • Other relevant fields

Institutional involvement in this study was on a competitive basis.

Participant clinical centers, in addition to UPMC, include:

  • East Carolina University
  • Neuropsychiatric Research Institute, University of North Dakota
  • New York Columbia-Presbyterian/Cornell University Medical Center
  • Oregon Health and Sciences University
  • University of Washington

The data coordinating center for the entire project is located in the Graduate School of Public Health at the University of Pittsburgh.

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Objective: The first phase, LABS-1, had a short-term focus on the safety of bariatric procedures.

Total participants: 5,965

  • Nationally: 5,098
  • University of Pittsburgh: 867

Outcome: The collected data will result in many publications to help bariatric surgical clinicians provide better care. For example, see the landmark New England Journal of Medicine publication documenting the relative safety of bariatric surgery.

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The second phase, LABS-2, began enrolling participants at UPMC on February 27, 2006.

Objective: The primary objective is to use standardized techniques and measures to assess the longer-term safety and effectiveness of bariatric surgery by:

  • Comparing post-surgical outcomes to pre-operative status
  • Examining risks and benefits of surgery

Total participants: 3,063

  • Nationally: 2,501
  • University of Pittsburgh: 562

Outcome: LABS-2 is currently granted to follow participants for as long as eight years after their bariatric surgery. We are hopeful that future grants will extend this time.

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Teen LABS Corollary Study

Teen LABS - for adolescents who have bariatric surgery — is a multicentered study by the University of Pittsburgh along with:

  • Cincinnati Children's Hospital Medical Center
  • Texas Children's Hospital at Baylor University
  • University of Alabama at Birmingham

Objective: In addition to having the same objectives as LABS-2, Teen LABS will:

  • Determine whether health significantly differs between adolescents and adults seeking bariatric surgery;
  • Identify risks for adolescents undergoing bariatric surgery; and
  • Compare the psychosocial status of adolescents and adults with extreme obesity undergoing surgery.

Participants: The recruitment goal is 200 participants. If interested in participating in the Teen LABS study, please call 412-641-3632.

Outcome: TBD

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