"There is no clear answer at this time. Nor was there a clear answer when the guidelines for lung transplantation were written in 1998. They were based on the best clinical data then available," explained Dr. Philip W. Smith, a surgery resident and research fellow at the University of Virginia Health System.
Since lung transplantation (LTX) was first performed in 1983, it has been a viable therapy for patients with progressive end-stage lung disease. However, transplant centers have found it necessary to adhere to patient age restrictions for LTX because supplies of donor organs are scarce and mortality risks for the elderly are high.
While they have risen in recent years, the recommended age limits for LTX are now 60 for bilateral lung transplantation (BLT) and 65 for single-lung transplantation (SLT). These guidelines are based on the experience of academic institutions such as UVa, which is among several centers now exploring if further revisions are reasonable.
According to Smith, age restrictions are a pressing issue for the medical community because the number of people age 60 and older is growing rapidly, and this group will soon constitute a quarter of the U.S. population.
Smith said that he and Dr. David R. Jones, surgical director of UVa's Lung Transplant Program, were concerned about categorically excluding the elderly from receiving LTX. "This concern prompted the retrospective study we recently completed," Smith said.
Published last month in The Annals of Thoracic Surgery, the study reviewed the outcomes of 182 LTX recipients treated at UVa between 1995 and 2005. Of those patients, 52 (or 29 percent) were between 60 and 69 years old. Sixteen patients (or 9 percent) were aged 65 or older.
"Age is not an independent exclusion criterion at our center," noted Jones. "All patients undergo the same pre-transplant evaluation to determine their eligibility. Our study shows that lung transplantation can be performed with acceptable outcomes in patients aged 60 and older, if the person is otherwise an appropriate candidate."
With the exception of recipient-age recommendations, UVA follows the International Guidelines for the Selection of Transplant Candidates in choosing LTX recipients.
Study findings showed that lung transplant recipients age 60 and older have a major survival advantage at UVa compared to patient data compiled by the United Network for Organ Sharing (UNOS), a national registry that tracks outcomes at U.S. transplantation centers. Five-year survival rates of patients in this age group were 54.7 percent at UVa and 38.6 percent in the UNOS database.
Researchers found that survival rates for UVa's younger LTX patients also exceeded those reported by UNOS. The five-year survival rate for LTX patients under 60 was 61.0 percent at UVa and 49.8 percent among UNOS registrants.
The researchers attributed UVa's results to several factors. "Our findings show that the quality of care provided during the very early period following a lung transplant is key to long-term success for elderly recipients. We've established a multidisciplinary team to ensure that optimal care is provided during this crucial time," said Jones.
Another factor, noted Smith, is that UVa "almost exclusively performs SLT rather than BLT for recipients aged 60 and older - and we do so at a significantly higher rate than other transplant centers. We believe that this is the most appropriate procedure for the vast majority of these patients."
During the study's timeframe, only one elderly patient at UVa received BLT rather than SLT.
"The issue of which procedure yields the best outcomes for older patients remains unresolved," Smith said. "Some centers are performing more BLT on older patients and believe that to be the appropriate approach. At some point, the collective experience, including this study, will be reviewed and the guidelines will be adjusted accordingly.