Shorter telomeres — the DNA regions that protect the ends of chromosomes — are linked to lower survival rates in pulmonary fibrosis (PF) patients who receive a lung transplant. These patients’ lungs start failing sooner than those of other patients, suggesting that telomere length may be a factor to consider for physicians selecting candidates for lung transplant.
The study, “Telomere length in patients with pulmonary fibrosis associated with chronic lung allograft dysfunction and post-lung transplantation survival,“ appeared in The Journal of Heart and Lung Transplantation.
“Patients with idiopathic pulmonary fibrosis (IPF) account for the largest proportion of patients awaiting, and dying while awaiting, lung transplantation,” wrote researchers from the University of Texas (UT) Southwestern Medical Center in Dallas.
Yet the survival rate for PF patients even after getting a lung transplant isn’t that long. On average, they live 4.7 years, compared to 5.7 years for those receiving transplants for other conditions.
Efforts are always ongoing to identify patients who will have the greatest likelihood of good outcomes after a lung transplant. Since many IPF patients have telomere abnormalities, the UT Southwestern team figured that telomere length might also determine how well a patient tolerates a lung transplant.
To find out, researchers enrolled 82 IPF patients who had lung transplants between 2007 and 2014. All patients had their telomere length analyzed with the help of a blood test, and researchers divided patients into two groups: short and long telomeres. Researchers followed the patients for an average of five years after the transplant.
Twenty-six patients, or 32 percent, had short telomeres. These patients were compared to those with longer telomeres.
While the two groups showed little difference in terms of lung disease severity, analyses showed that the 26 patients with shorter telomeres had poorer survival rates. Among those with short telomeres, 54 percent died during the study, while only 18 percent of those with longer telomeres died. Those with shorter telomeres also died sooner after the transplant.
Although patients with short telomeres died of different types of complications, the analyses showed that their transplanted organ was more likely to fail, and fail sooner, than those with long telomeres.
Researchers found no difference in acute rejection, infections, blood cell count drops, or kidney disease between the groups.
“In conclusion, telomere length represents a potential biomarker that can easily be assessed during the pre-transplant evaluation to identify patients at increased risk for post-transplant complications,” the team wrote. “The results from this single-site study are compelling and warrant replication in a larger, multi-center cohort.”