The Relationship between Cognitive Reserve and Neuropsychological Outcomes after TBI. (P7.186)

OBJECTIVE: The objective of this study is to investigate the relationship between estimated premorbid IQ and neuropsychological outcome measures following TBI. BACKGROUND: The cognitive reserve (CR) hypothesis postulates that the reason some persons perform better than others following TBI may be attributed to one’s pre-morbid cognitive functioning 1 . The level of education and IQ are considered indicators of CR 2 . Studies on TBI have found that pre-morbid IQ was the most commonly associated variable reflecting CR 4 . DESIGN/METHODS: The participants had suffered a TBI and were selected from a larger natural history study. The subjects were of varying TBI severities. Participants were assessed at one year post-injury for neuropsychological functioning in five cognitive domains: executive functioning, attention and processing speed, sensory motor function, memory, and language. Participants’ premorbid IQ was measured using the Test of Premorbid Function (ToPF). Pearson correlation between Test of Premorbid Functioning and all of the cognitive domains were assessed. We hypothesized that higher premorbid IQ will be correlated with improved cognitive outcomes following TBI. RESULTS: The subjects were 35 individuals (22 males and 13 females). Their average age was 45.1 (17.2) years. The average years of education were 15.4 years. Pearson correlation identified significant positive associations between ToPF and attention and processing speed, executive function, language, memory, and sensory motor function. CONCLUSIONS: Previous studies have used IQ scores as a measure of cognitive reserve. We used the ToPF to estimate premorbid IQ as a marker of cognitive reserve. The results in this study show that higher ToPF scores are correlated with higher scores on neuropsychological outcome measures in each of the listed cognitive domains. Together, these findings suggest that higher cognitive reserve is positively correlated with higher one year, neuropsychological outcomes following TBI. Study Supported by: Funded by the NIH and DoD. Disclosure: Dr. Hussain has nothing to disclose. Dr. Sacco has nothing to disclose. Dr. Leary has nothing to disclose. Dr. McNally has nothing to disclose. Dr. Lopez has nothing to disclose. Dr. Dsurney has nothing to disclose. Dr. Chan has nothing to disclose.