Predictors of the trajectory of cognitive functioning in the first 6 months after allogeneic hematopoietic stem cell transplantation

Certain subgroups of patients may be particularly vulnerable to cognitive decline after treatment with allogeneic hematopoietic stem cell transplant (HCT). The objective of this study was to identify predictors of cognitive functioning changes within the first 6 months after HCT. Fifty-eight adults treated with allogeneic HCT (53% male, mean 48 years of age) completed neuropsychological tests of learning/memory, psychomotor efficiency/processing speed, and executive functioning/working memory at three time points: pre-HCT and day 100 and 6 months post transplant. On average, there was significant improvement in learning/memory (p= 0.002), psychomotor efficiency/processing speed (p< 0.0001), and executive functioning/working memory (p< 0.0001), at 6 months. Multilevel modeling identified predictors of divergence from this trajectory; Karnofsky performance status <80 was associated with worsening learning/memory over time; peak severity of acute graft-versus-host disease >=Grade 2 was associated with worsening psychomotor efficiency/processing speed; and greater years of education predicted a faster improvement in psychomotor efficiency/processing speed. Other factors were associated with cognitive functioning over time: higher intelligence quotient (IQ) was associated with better cognitive functioning, and older age, being male, and greater pretransplant comorbidities were associated with worse cognitive functioning. Overall, cognitive performance appears to improve over the first 6 months after transplant. However, pretransplant and posttransplant factors may influence this trajectory.