Photo by Chad McNeeley
Leukocyte telomere length is associated with survival in patients who undergo hematopoietic stem cell transplant (HSCT) to treat severe aplastic anemia, according to research published in JAMA.
But it’s the donor’s telomere length—not the recipient’s—that makes the difference, the study showed.
Patients who received an HSCT from an unrelated donor had better overall survival at 5 years if that donor’s leukocytes had longer telomeres.
Shahinaz M. Gadalla, MD, PhD, of the National Cancer Institute in Rockville, Maryland, and colleagues conducted this research.
The group compared recipient and donor leukocyte telomere length prior to transplant with outcomes after unrelated HSCT for 330 patients with severe aplastic anemia.
The patients and their donors had pre-HSCT blood samples and other clinical results available at the Center for International Blood and Marrow Transplant Research. Patients underwent HSCT between 1989 and 2007 in 84 centers and were followed until March 2013.
The researchers categorized leukocyte telomere length for both recipients and donors based on the leukocyte telomere length tertiles in the donors: long (third tertile) and short (first and second tertiles combined).
The team found that longer donor leukocyte telomere length was associated with a higher overall survival. The 5-year overall survival was 56% in the longer telomere group and 40% in the shorter telomere group (P=0.009).
After adjusting for donor age and clinical factors associated with survival following HSCT in severe aplastic anemia, the risk of post-HSCT all-cause mortality remained approximately 40% lower in patients receiving HSCT from donors with long vs short leukocyte telomeres (hazard ratio [HR]=0.61).
There was no association between donor leukocyte telomere length and engraftment at 28 days (HR=0.94). Likewise, there was no association between telomere length and acute (HR=0.77) or chronic graft-vs-host disease (HR=0.81).
And recipient telomere length was not associated with overall survival (HR=0.91).
The researchers said these results suggest that donor leukocyte telomere length may have a role in long-term post-transplant survival. Authors of a related editorial explored what this discovery could mean for transplant centers.
