Changes in cognitive functioning in the year after hematopoietic stem cell transplantation

Abstract

BACKGROUND. The current study examined changes in multiple domains of cognitive functioning of hematopoietic stem cell transplantation (HSCT) candidates tested pretransplantation, 6 months posttransplantion, and 12 months posttransplantion. METHODS. Using a sequential longitudinal design, 476 patients were randomized to be tested at all 3 timepoints, at 6 and 12 months posttransplantion, or at only 12 months posttransplantion. Participants completed a comprehensive battery of neuropsychologic tests that indexed memory, psychomotor speed, attention, and executive functioning, and provided a total neuropsychologic performance score (TNP). RESULTS. The results indicate that performance on cognitive abilities, except for attention, significantly improved across the 1-year follow-up period after HSCT. Performance on the TNP and all cognitive domains was superior or equal to population normative values by the 12-month measurement point. The results also indicate that repeated exposure to tests led to better performance on motor speed and the TNP and that attrition influenced the TNP, such that those who remained in the longitudinal sample exhibited greater longitudinal improvement in scores as compared with patients who left the sample. CONCLUSIONS. The findings of the current study suggest that although patients undergoing HSCT experience cognitive deficits during the period just before transplantion, cognitive functioning returns to normative values within a year after transplantion. © 2007 American Cancer Society.