DURHAM, N.C. -- Medical researchers hope that an unusual clinical trial will prove whether or not removing portions of lungs can provide long-term benefit to patients severely disabled by emphysema, a progressive lung disease for which there is no other cure.
The trial's findings are both medically and economically important, researchers say, because it is estimated that there are currently more than 10 million Americans with emphysema and the procedure costs $50,000 to $60,000. Most of these patients are usually elderly and disabled and are covered by Medicare, the federal insurance program.
Medicare had paid for thousands of the procedures in the early 1990s, when many hospitals began offering it to enthusiastic patients. Although short-term benefits were observed in many patients, important unanswered questions included the duration of benefit, which patients were most suitable, and what were the potential short- and long-term complications, researchers said.
The National Emphysema Treatment Trial, which is now enrolling the first of a planned 4,700 patients, is being carried out in 18 centers across the country. Patients will be enrolled for three to five years, and will be followed for at least five years.
Duke University Medical Center is the only hospital in the Southeast participating in the trial.
Funded jointly by the National Heart, Lung, and Blood Institute (NHLBI) and the Health Care Financing Administration (HCFA), the agency that handles Medicare claims, this is the largest clinical trial the two federal agencies have combined to sponsor.
"This can be the model of how Medicare and other third-party payers can work together with researchers to evaluate new procedures," said pulmonologist Dr. Neil MacIntyre, Duke's principal investigator in the trial. "Instead of just deciding arbitrarily whether or not a specific procedure or therapy is effective and should be covered, the government is funding a trial to actually find out the answer.
"Because of the large numbers of patients and way the trial has been designed, we should get definitive answers on the role of this procedure."
In the procedure, known as lung volume reduction surgery (LVRS), surgeons remove portions of the lung that have become overinflated from the disease. This allows undiseased portions of lung -- which had been compressed by diseased lung tissue -- to expand and function properly. The removal of the inflexible portions of lung also improves the ability of the diaphragm to function in a more normal manner, MacIntyre said.
The first surgeries were performed in the early 1950s and although some patients regained a degree of lung function, one in six patients died. Because surgeons had difficulty controlling air leaks after surgery, the procedure fell out of favor.
However, with the advent of improved surgical techniques, surgeons revisited the procedure in the early 1990s.
"Studies involving small numbers of patients in the surgical literature showed significant improvements in lung function tests and exercise tolerance, with early mortality rates between 2 percent and 7 percent," MacIntyre said.
When success stories began appearing in the popular press about the benefits of the procedure, many emphysema patients demanded it. By 1995, many hospitals jumped on the bandwagon and offered the new surgical approach to their emphysema patients.
As the popularity of LVRS grew, so did the number of claims submitted to Medicare for reimbursement. In 1992, between 200-300 claims were submitted for the procedure; by 1995, the number had jumped to more than 2,000.
"For obvious reasons, HCFA began tracking claims," MacIntyre said. "After studying 711 consecutive claims, they found that 26 percent of the patients were dead after one year, there was a 40 percent rehospitalization rate, and 16 percent needed long-term care.
"Clearly, there was quite a difference between what was being reported in the literature and what HCFA found."
So in January 1996, HCFA halted reimbursements for LVRS, and called for a large-scale trial to determine the effectiveness of the procedure and to determine which patients would benefit the most from surgery. In December of last year, HCFA and the NHLBI announced the trial and the 18 participating centers, who have worked for the past year designing the trial.
"It is obvious to us that while many patients may benefit from the procedure, patients could also be harmed," MacIntyre continued. "It is important to sort these things out before making a blanket statement about the benefits of LVRS."
To be eligible for the trial, patients must have moderate to severe emphysema, have no other complicating medical problems, and must have quit smoking for at least four months. The vast majority of these emphysema cases are the result of smoking, MacIntyre said.
"In general, these patients get short of breath at mild exertion, some are on oxygen, and most are unable to carry out the routine activities of everyday life," MacIntyre said. "It is truly a debilitating disease for which little can be done."
Patients must be Medicare-eligible to participate in the trial. Many hospitals, including Duke, continue to offer the surgery, but patients may have to pay for it out of their own pocket, because many insurers do not cover the operation. Like the federal government, they are awaiting the outcome of the trial, MacIntyre said.
All participants in the trial will receive intensive medical therapy and rehabilitation and half will be selected by random for LVRS.
Those picked for surgery will be further separated randomly into two different surgical approaches -- either by median sternotomy (open chest) or by video assisted thoracic surgery (VATS). At Duke, Dr. Duane Davis will perform the open surgery, while Dr. David Harpole will use the VATS approach.
Duke pulmonologist Dr. Victor Tapson and study coordinator Abby Krichman will evaluate potential patients and will be in charge of the medical care of study participants, while MacIntyre serves as director of the Duke pulmonary rehabilitation program.
Study participants will be evaluated for exercise ability, lung function, quality of life, illness and survival. Although it has been estimated that it will take seven years to complete the trial, treatment recommendations may be made sooner if the data, which will be reviewed at regular intervals by an independent panel of experts, show clear-cut benefits or risks.
"If it is determined that the surgery is clearly beneficial, those patients who had been randomized to maximum medical care alone will be offered the surgery immediately," MacIntyre said. "Likewise, if the surgery is doing more harm than good, the trial will be stopped."
Current treatment for patients in the final stages of emphysema is largely supportive, including nutritional supplementation and exercise rehabilitation. Lung transplantation may be an option for some patients under age 60, but donor lungs are scarce, and the procedure is expensive.
Materials provided by Duke University Medical Center. Note: Content may be edited for style and length.
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