Purpose: Hematopoietic stem cell transplant (HSCT) recipients are at risk for cognitive decline. Cross-sectional studies show patients' complaints of cognitive decline do not correlate well with concurrently measured objective neuropsychological performance, but rather with emotional variables and health-related quality of life. This longitudinal study investigated whether patient self-report of cognitive status would be concordant with objectively measured neuropsychological performance after accounting for change from their own pre-transplant objective baseline.
Methods: Pre-HSCT and at 30 and 100 days post-HSCT, 46 patients underwent computerized neuropsychological testing (CogState) and completed surveys assessing patient-reported cognitive complaints, emotional symptoms (depression, anxiety), sleep quality, daytime sleepiness, and physical and functional well-being. Correlations were calculated between cognitive complaints and neuropsychological performance (at each time-point and across time-points), as well as all other patient-reported variables.
Results: Patient-reported cognitive complaints were largely independent of concurrently assessed objective neuropsychological performance. Uniquely, our longitudinal data demonstrated significant medium to large effect size associations between subjective cognitive complaints post-HSCT with objectively measured change from pre-HSCT in attention, visual learning, and working memory (p < .05-.01). Subjective cognitive complaints post-HSCT were also associated with depression, anxiety, daytime sleepiness and physical well-being (p < .05-.001).
Conclusions: Patients appear better able to assess their cognitive functioning relative to their own baseline and changes across time rather than relative to community norms. Thus, patient complaints of cognitive compromise justify further in-depth neuropsychological, emotional, and functional assessment. Future research into relationships between cognitive complaints and neuropsychological performance should account for changes in performance over time.
Keywords: Cancer; Cognition; Cognitive dysfunction; Hematopoietic stem cell transplantation; Neuropsychological tests; Oncology.