Self-Rated Health Is an Independent Predictor of Late Mortality after Blood or Marrow Transplantation (BMT) Among Survivors of Plasma Cell Disorders: A BMTSS Report

Background: BMT is offered with curative intent to patients with plasma cell disorders (PCD) and other life-threatening illnesses. Despite the decline in early mortality due to refinement in transplantation strategies and advances in supportive care, BMT recipients carry a significant burden of late-occurring morbidity, placing them at high risk for late mortality when compared with the general population. Self-rated health (SRH) is a single-item measure of an individual’s evaluation of their health status and has been reported as an independent predictor of mortality in the general population and cancer patients treated with conventional therapy. The association between SRH and subsequent all-cause mortality among BMT survivors of PCD has not been examined. Finally, sociodemographic and clinical factors associated with suboptimal SRH among BMT survivors remain unstudied.

Methods: We examined the prevalence of suboptimal SRH and its association with subsequent all-cause mortality after BMT among survivors of PCD. Study participants were drawn from BMTSS and included PCD patients who were transplanted between 1974 and 2014 at three participating sites, and had survived ≥2y post-BMT. Participants (≥18y) completed a survey at a median of 6y from BMT and were followed for a median of 4y after survey completion for vital status and cause of death. Survivors provided information on sociodemographic characteristics, chronic health conditions (as diagnosed by their healthcare providers), health behaviors, and SRH (single item, rated as excellent, very good, good, fair or poor; excellent, very good or good SRH were classified as good SRH and all else as suboptimal SRH). National Death Index (NDI) Plus, Accurint database, and medical records provided vital status through December 2021. Multivariable regression analyses determined the association between SRH and all-cause mortality (Cox regression) after adjusting for relevant sociodemographic, clinical variables and therapeutic exposures. Factors associated with suboptimal SRH were analyzed using multivariable logistic regression.

Results: The cohort included 595 participants; 96.0% autologous BMT; median age at BMT 59y; 57.8% males; 66.9% non-Hispanic whites. Overall, 185 (31.1%) survivors reported suboptimal SRH and 177 died after survey completion (29.8%). BMT survivors who reported suboptimal SRH had a 2.5-fold greater hazard of all-cause mortality (95%CI=1.8-3.4) compared to those who reported good SRH, after adjusting for age at survey, year of BMT, sex, race/ethnicity, socioeconomic status (SES), age at BMT, risk of relapse at BMT (standard; high), post-BMT relapse and grades 3-4 chronic health conditions. Pain, male sex, psychological distress, lack of exercise, smoking, post-BMT relapse and pre-BMT radiation were associated with suboptimal SRH.

Conclusions: This single-item measure could serve to identify vulnerable sub-populations of PCD patients with sub-optimal self-rated health that could benefit from interventions to mitigate the risk for late mortality.