Impact of Allogeneic Hematopoietic Cell Transplant on Neurocognitive Function

Background Allogeneic hematopoietic cell transplant (HCT) is associated with significant morbidity and mortality, including neurocognitive dysfunction post-transplant. Studies assessing cognitive function in HCT patients is limited. This single institution, retrospective analysis investigates the change in cognitive function post-allogeneic HCT and its association with post-HCT outcomes. Methods We performed a retrospective analysis on patients receiving allogeneic HCT at the Cleveland Clinic between January 1, 2016 and December 31, 2022 with available neurocognitive screening at both pre-HCT and day 100 time points. Neurocognitive screening was performed using the Brief Assessment of Cognitive Health (BACH), a self-administered electronic tool measuring multiple domains of function, as well as data on sleep (average hours), stress (scale 0-100) and depression (measured by PHQ-8), developed and validated at the Cleveland Clinic. BACH scores reflect probability (%) of cognitive impairment. We investigated change in BACH, sleep, stress, and depression scores between pre-HCT and day 100; correlations between cognitive function and sleep, stress, and PHQ-8; and association of low and high BACH (based on the median) with graft-versus-host disease (GVHD), non-relapse mortality (NRM), relapse and overall survival. Results A total of 150 patients with pre-HCT BACH assessment were identified. Of those, 44 patients had longitudinal BACH scores at day +100. Median age at transplant was 65 years (range, 47-75). The majority (N=31, 71%) received reduced-intensity conditioning. Median probability of cognitive impairment was 22% (range, 8-67%) pre-HCT, without significant change at day 100 (27% (7-87%)), p=0.43. There was also no significant change in sleep, stress, and PHQ-8 scores pre- and post-HCT (Table 1). Stress had a positive correlation with PHQ-8 (Spearman r 0.32, p=0.04), but no other domains were found to be significantly correlated. Cognitive functioning, sleep, and stress were not associated with any outcomes including GVHD, NRM, relapse, or survival; however, PHQ-8 score (≥2) was significantly associated with NRM (HR, 2.87; 95% CI, 1.13-7.23; p=0.03) (Table 2). Conclusion Neurocognitive function does not appear to change significantly in the first 100 days post-HCT or impact post-HCT outcomes. Although our study is limited by small sample size, we demonstrate an association of pre-HCT depression and NRM. Further longitudinal characterization of neurocognitive function and longer-term outcomes in a larger cohort is planned.