Cognitive function, quality of life, and aging: relationships in individuals with and without spinal cord injury

Background: Correlations between aging, cognitive impairment and poor quality of life (QOL) have been observed for many patient populations. Objective: The purpose of this study was to examine these correlations in individuals with and without spinal cord injury (SCI). Methods: 23 individuals with complete SCI and 20 individuals without SCI ("NON") underwent assessment of cognitive function via the NIH Toolbox for Neurological and Behavioral Function. Participants self-rated QOL via global and symptom/domain-specific measures. Results: SCI rated global QOL to be lower than NON for the EQ-5D QALY (p < .001), but not the EQ-5D VAS, which imposes no penalty for wheeled mobility. Low QOL clustered mainly in domains pertaining to physical function/symptoms. Participants with SCI reported high QOL for positive affect/well-being and resilience. Cognitive function in SCI did not differ from NON. However, strong correlations between age and cognition observed in NON (all R-2 > 0.532) were absent in SCI. Significant correlations between cognition and QOL were prevalent for NON but not for SCI. Conclusions: Dissociation of age, cognition and QOL occurred with SCI. Divergence between EQ-5D QALY and VAS suggests that individuals with SCI may recalibrate personal assessments of QOL in ways that minimize the importance of mobility impairment.