The value of stent surgery are in question again as a study released Sunday showed the heart devices, combined with drug therapy, did no better at reducing deaths or heart attacks among certain diabetes patients when compared against drugs alone.

The study, formally released at the American Diabetes Association conference and simultaneously published in the New England Journal of Medicine, will surely be hotly debated among leading stent makers such as Johnson & Johnson (JNJ) and Abbot Laboratories Ltd. (ABT), and the broader medical community.

The results essentially replicate the findings of a study released in 2007, called Courage, that shook the medical community, said Dr. William Boden and Dr. David Taggart in a NEJM editorial that accompanied the study.

The two studies do have significant differences, though. The recent study, called BARI 2D, focused on a more limited patient group - those who have Type 2 diabetes and evidence of limited blood flow to a major organ, also called ischemia. The Courage study followed diabetic and non-diabetic patients with stable coronary heart disease.

Analysts and medical device makers predict the recent study will have minimal impact on major medical device makers because many people expected the new study to have results similar to Courage. Indeed, Abbott Laboratories doesn't expect the study to "have any impact on stent volumes," said spokesman Jonathon Hamilton. Hamilton said the company based its decision on the fact that most patients were given bare-metal stents instead of drug-eluting stents, considered the newest generation of the devices, which prop open arteries and use medication to stop the artery from renarrowing.

Dr. Robert Frye, professor of medicine at the Mayo Clinic, said at a press briefing that wider use of drug-eluting stents wouldn't have made much of a difference, citing studies showing the new generation of stents don't reduce deaths or heart attacks any better than older version.

Other doctors questioned the design of the study. "These patients don't represent every diabetes patient that walks through the door," said Dr. Steven Bailey, president of the Society for Cardiovascular Angiography and Interventions. He also said the "incredible" drug treatment these patients were given is hard to replicate in the real world, where patients often don't show up on time and variables such as insurance play a factor in how someone is treated.

Bailey is on the speakers' bureaus of several medical device makers, including Abbott and Medtronic Inc. (MDT).

The study was sponsored by the National Institutes of Health and several drug companies, and set out to answer several questions, including whether diabetes drugs that help the body use insulin more effectively work better than injecting insulin.

The study shows that patients on GlaxoSmithKline Plc's (GSK) Avandia or Takeda Pharmaceutical Co.'s (4502.T0) Actos had a similar death rate than those taking insulin. The study also noted no increase in heart attacks with Avandia, a drug that has been dogged by concerns that it boosts heart risks.

The study also highlights the important role comparative effectiveness research plays in making medical decisions, said Dr. Richard Kahn, chief scientific and medical officer of the American Diabetes Association.

President Barack Obama has said research comparing medical treatments, known as comparative effectiveness, is a hallmark of health care reform and committed $1.1 billion for such studies. Kahn said this study "is what comparative effectiveness is all about."

-By Jared A. Favole, Dow Jones Newswires; 202.862.9207; jared.favole@dowjones.com