Children and adolescents who are wait-listed for lung transplantation and have the worst functional status are at the greatest risk of being removed from the waitlist due to clinical deterioration or death, a study reports.
The risk is highest for patients with cystic fibrosis (CF) and for adolescents compared with younger children, data indicate.
“Functional status at waitlist registration may be an important and potentially modifiable risk factor to improve survival to lung transplant for children and adolescents,” researchers wrote.
The study, “Poor Functional Status at the Time of Waitlist for Pediatric Lung Transplant is Associated with Worse Pre-Transplant Outcomes,” was published in the Journal of Heart and Lung Transplantation.
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Lung transplant recommended for severe hard-to-treat CF
Lung transplant may be recommended for patients with severe CF, particularly those whose disease has failed to respond to treatment. Patients are added to a waitlist for healthy lungs, but many clinically deteriorate or die while waiting for a transplant.
Investigators at the Perelman School of Medicine at the University of Pennsylvania sought to determine which factors at the time of waitlist registration were associated with pre-transplant outcomes in adolescents and children candidates, ages 1-17, for lung transplant.
The team collected data on lung transplant registrants from 2005 to 2020 using the UNOS Standard Transplant Analysis and Research files, which provided data from centers in the U.S.
Overall, 964 patients were included in the analysis, of whom 63.5% were 12-17 years of age, 58.5% were female, and 69% were white. CF was the most common reason for lung transplant (50.2%), followed by pulmonary hypertension (13.5%), or high blood pressure in the blood vessels that supply the lungs.
Functional status, assigned to each transplant patient at registration, was measured using the Lansky Play Performance Scale (LPPS).
At the time of waitlist registration, 25.6% had LPPS scores from 10-40, meaning they were completely dependent and needed constant care (mostly/constantly bedridden). Moderately dependent (less/no active play) was assigned to 52.5%, with scores from 50-70, while 21.9% were minimally dependent or independent, scoring from 80-100.
Children and adolescents waitlisted for lung transplantation with the worst functional status had worse pre-transplant outcomes and had the greatest risk of waitlist removal due to death or clinical deterioration.
20% removed from waitlist after 3 months due to clinical deterioration or death
During a median of 95 days on the waitlist, 20.1% of patients were removed from the waitlist due to clinical deterioration or death, while 68.2% were removed from the waitlist due to clinical improvement or transplant.
Compared to minimally dependent or independent patients, those assigned completely dependent functional status at the time of waitlist registration were 5.3 times more likely to be removed from the waitlist due to clinical deterioration or death.
This association was even stronger for CF patients, with their outcomes primarily contributing to the overall effects on pretransplant outcomes.
Dependent status was also linked to a 2.3 times higher chance of waitlist removal due to clinical improvement or transplant.
These findings were statistically corrected for factors that may influence the outcome, including sex, age, ethnicity, diagnosis, dependence on breathing support, year, listing center volume, and extracorporeal membrane oxygenation, which is a procedure wherein blood is pumped outside the body to a heart-lung machine that removes carbon dioxide and sends oxygen-filled blood back to the body.
Higher risk of removal from transplant waitlist for adolescents, CF patients
When examined by age, patients 12 years and older who were completely dependent were 9.26 times more likely to be removed from the waitlist for death or clinical deterioration. In comparison, those under 12 had a 3.81 times elevated risk. Sex did not influence these results.
Being moderately dependent increased the risk of waitlist removal for lung transplant or clinical improvement by 36% compared to minimally dependent/independent patients. Sex and age did not affect waitlist removal due to clinical improvement or transplant.
“Children and adolescents waitlisted for lung transplantation with the worst functional status had worse pre-transplant outcomes and had the greatest risk of waitlist removal due to death or clinical deterioration,” the investigators concluded.
“This association was stronger for adolescents compared to younger children and particularly strong for patients with CF,” they noted.