Study results inform discussions on US policy for lung transplantation in children

According to the lung allocation policy in place in the United States since 2005, lungs from adolescent donors (aged 12 to 17 years) are preferentially offered to adolescent candidates; if there are no suitable adolescent candidates in the local donation service area, the organ is offered to a local candidate aged 0 to 11 years. Earlier this year, though, a US Federal Court directed the Secretary of Health and Human Services to allow a 10-year-old patient to be considered alongside older candidates for lungs from adolescent and adult donors without consideration of her age. The plaintiff's filing included data indicating that death rates for patients on the waiting list were higher for children younger than 12 years of age than for adolescents and adults.

Bertram Kasiske, MD, of the Scientific Registry of Transplant Recipients (SRTR) in Minneapolis, led a team that examined the validity of those data. "In our capacity as researchers who support the policy process, we addressed whether or not children in the 6 to 11 age range, whose size might afford them benefit from access to lungs from donors aged 12 and older, were greatly disadvantaged by the current policy," said Dr. Kasiske. The researchers analyzed information from the Scientific Registry of Transplant Recipients, which includes data on all donors, wait-listed candidates, and transplant recipients in the United States. The investigators looked specifically at mortality rates by age for candidates registered on the lung transplant waiting list between January 1, 1999, and December 31, 2011.

The team found that children aged 6 to 11 years who are on the waiting list die at a rate that is similar to older candidates. For children aged 0 to 5 years, death rates are higher compared with older children and adults, but transplant rates are not lower compared with other age groups. The researchers also discovered that children aged 6 to 11 years were transplanted at lower rates in the years immediately following implementation of the 2005 lung allocation policy; however, this difference seems to have disappeared in recent years.

"The Thoracic Transplantation Committee of the Organ Procurement and Transplantation Network (OPTN) will be re-evaluating lung allocation policy as it applies to children during late 2013 and early 2014. This research will help inform the debate about pediatric lung allocation policy," said Dr. Kasiske.

In an accompanying editorial, Stuart Sweet, MD, PhD, of Washington University in St. Louis, and Mark Barr, MD, of the University of Southern California in Los Angeles, noted that there are several other factors that should be considered as officials and the transplant community consider whether changes to pediatric lung allocation are warranted. "Opportunities for improvement include bringing the lung donor yield in the 0-11 age group closer to the yield in adolescents, relaxing geographic allocation boundaries to ensure that pediatric lungs are offered first to children, and reserving deceased donor lobar transplant for circumstances where suitably sized donor organs are not available," they wrote.