0729 Sleep Apnea Diagnosis And Severity And Their Impact On Cognition After TBI: A VA TBI Model Systems Study

Introduction For persons with moderate-to-severe traumatic brain injury (TBI), chronic cognitive impairment contributes to long term disability. Health comorbidities may contribute to the neurologic burden in TBI. Indeed, obstructive sleep apnea (OSA) is associated with neuropathological and cognitive changes. The objective of this study was to examine the relationship between OSA and cognition after TBI. Methods Participants were prior inpatient rehabilitation patients drawn from the Tampa VA TBI Model Systems longitudinal study. Post-discharge interviews occurred 2 to 6 years post-TBI. Participants reported whether they were diagnosed with OSA and completed the Brief Test of Adult Cognition by Telephone (BTACT) which measures recall, working memory, processing speed, fluency, and reasoning. Participants with polysomnography (PSG) were separately analyzed to examine the impact of sleep apnea severity (i.e., Apnea-Hypopnea Index [AHI]) on cognition. Results Participants (N=104) were mostly male (95.2%), age M=37.7 (SD=12.5), Education M=13.6 years (SD=2.1), and 45.2% were diagnosed with OSA. Participants with and without OSA did not differ by age, education, gender, or time since injury at time of BTACT (ps > .05). ANCOVAs were conducted examining OSA diagnosis on BTACT subscale scores, covarying TBI severity level, but results did not reach statistical significance (ps > .05). A subset of participants with OSA had PSG (n=27), AHI score quartiles = 6.7/10.4/21.6. Higher AHI was associated with poorer reasoning (Spearman ρ = -0.45, p = .019). Nonsignificant results were found for word recall (Spearman ρ = -0.35, p = .074) and processing speed (Spearman ρ = -0.36, p = .069). Conclusion Severity of sleep apnea may influence aspects of cognition among persons with TBI, although these results are preliminary and need replication with a larger and more representative sample. Support This work was supported by the Veterans Health Administration Central Office VA TBI Model Systems Program of Research and subcontract from General Dynamics Information Technology [W91YTZ-13-C-0015, HT0014-19-C-0004] from the Defense and Veterans Brain Injury Center (DVBIC); and from the United States Department of Veterans Affairs [W81XWH-13-2-0095]; and from the United States Department of Defense Congressionally Directed Medical Research Programs; and from the Patient Centered Outcomes Research Institute (PCORI) [CER-1511-33005].