Long-Term Outcomes of Exercise-Based Rehabilitation and Immunometabolic Parameters in Adult Haematopoietic Stem Cell Transplant Recipients: An Updated Systematic Review of Randomised Controlled Trials.

BACKGROUND

Adult haematopoietic stem cell transplantation (HSCT) survivors have deficits in physical function, fatigue and quality of life that differ between autologous and allogeneic recipients. Few randomised controlled trials (RCTs) have evaluated exercise at 3 months or more, and immune reconstitution is rarely assessed. We synthesised RCT evidence on longer-term exercise effects across physical, psychosocial and immunometabolic outcomes by transplant type.

METHODS

Following PRISMA 2020, six databases were searched (2019-2026) for RCTs comparing structured exercise with usual care or control in adults after HSCT, with outcomes at 3 months or more. Screening, extraction and risk-of-bias appraisal (Cochrane RoB 2) were conducted independently by two reviewers. Heterogeneity precluded meta-analysis; findings were synthesised narratively with GRADE certainty ratings.

RESULTS

Seven RCTs (529 participants; two allogeneic, two autologous and three mixed) reported no serious exercise-related adverse events. Between-group 6-min walk distance improved by approximately 51-63 m (significant in the largest trial) and sit-to-stand by 2.5-3.8 repetitions. Cardiorespiratory fitness, fatigue and quality-of-life effects were inconsistent, often within-group only. Benefit appeared larger in allogeneic recipients, whereas an autologous trial showed none. Immunometabolic data from two trials showed an exploratory reduction in soluble ICAM-1 and within-group recovery of body cell mass. Certainty was low to very low.

CONCLUSIONS

Exercise appears safe after HSCT and may improve objective physical function, with the greatest benefits observed in allogeneic and more impaired recipients. Cardiorespiratory, fatigue and quality-of-life effects remain uncertain, and immunometabolic evidence is preliminary. Future trials should report outcomes by transplant type and incorporate immune and metabolic endpoints with longer follow-ups.

TRIAL REGISTRATION: The authors confirm that clinical trial registration is not needed for this submission.