PRIMARY OBJECTIVES:~I. Examine associations between social support, strain, and isolation and phenotypic aging over the 1-year recovery period.~II. Examine associations between social support, strain, and isolation and biological aging over the 1-year recovery period.~III. Test biological aging as a mediator linking social processes and phenotypic aging.~EXPLORATORY OBJECTIVE:~I. Test sex differences in Aims 1 and 2.~OUTLINE:~Adopting a prospective design, participants will complete comprehensive assessments of social processes at 100 days and 1 year after HCT that combine reports of social support, strain, and isolation with a naturalistic observation tool, the Electronically Activated Recorder (EAR), which captures ambient sound bites to assess social interactions in survivors' daily lives16. At each time point, participants will also provide reports of symptoms to characterize phenotypic aging, including cognitive, physical, and functional complaints, and blood samples to assess biological aging, including cellular senescence, DNA damage, SASP, and cellular stress using genome-wide RNA sequencing. Relevant clinical information that could influence biological aging will also be collected from patients' medical records to consider as covariates.
This project aims to elucidate the important protective elements of social relationships and identify concrete, modifiable behavioral factors that contribute to biological and phenotypic aging in hematopoietic cell transplantation (HCT) survivors and can be used to develop biologically informed interventions to improve quality of life and prolong the healthspan of individuals with accelerated aging.