Cognitive Reserve Moderates Cognitive Outcome After Mild Traumatic Brain Injury

Abstract

To investigate whether cognitive reserve moderates differences in cognitive functioning between patients with mild traumatic brain injury (MTBI) and controls without MTBI and to examine whether patients with postconcussion syndrome have lower cognitive functioning than patients without postconcussion syndrome at 2 weeks and 3 months after injury. Design: Trondheim MTBI follow-up study is a longitudinal controlled cohort study with cognitive assessments 2 weeks and 3 months after injury. Setting: Recruitment at a level 1 trauma center and at a general practitioner-run, outpatient clinic. Participants: Patients with MTBI (nZ160) according to the World Health Organization criteria, trauma controls (nZ71), and community controls (nZ79) (NZ310). Main Outcome Measures: A cognitive composite score was used as outcome measure. The Vocabulary subtest was used as a proxy of cognitive reserve. Postconcussion syndrome diagnosis was assessed at 3 months with the British Columbia Postconcussion Symptom Inventory. Results: Linear mixed models demonstrated that the effect of vocabulary scores on the cognitive composite scores was larger in patients with MTBI than in community controls at 2 weeks and at 3 months after injury (PZ.001). Thus, group differences in the cognitive composite score varied as a function of vocabulary scores, with the biggest differences seen among participants with lower vocabulary scores. There were no significant differences in the cognitive composite score between patients with (nZ29) and without (nZ131) postconcussion syndrome at 2 weeks or 3 months after injury. Conclusion: Cognitive reserve, but not postconcussion syndrome, was associated with cognitive outcome after MTBI. This supports the cognitive reserve hypothesis in the MTBI context and suggests that persons with low cognitive reserve are morevulnerable to reduced cognitive functioning if they sustain an MTBI.

Prediction of risk of prolonged post-concussion symptoms: Derivation and validation of the TRICORDRR (Toronto Rehabilitation Institute Concussion Outcome Determination and Rehab Recommendations) score

“…Neurocognitive reserve capacity is a proposed protective mechanism that may enable some individual’s brain to adapt to or recover from pathology associated with neurological diseases and/or psychiatric disorders and is believed to decrease with the aging process [ 33 ]. Indeed, there has been some preliminary evidence to suggest that lower cognitive reserve is associated with worse cognitive outcome post-mTBI [ 34 ] as well as risk for persistent post-concussive symptoms [ 35 ].…”

Examining the Subacute Effects of Mild Traumatic Brain Injury Using a Traditional and Computerized Neuropsychological Test Battery

“…The sample included patients (n = 177) taking part in the extended Trondheim MTBI follow-up study, who had been examined with neuropsychological tests at 2 weeks after injury. The Trondheim MTBI Study enrolled 378 patients with MTBI between April 1, 2014, and December 5, 2015, 4 and around half were recruited to an extended follow-up study involving repeated neuropsychological testing, 37 blood sampling, 38 and brain MRI. 39 The participants were consecutively recruited from two emergency departments (EDs): St. Olav's Hospital, a regional Level 1 trauma center at Trondheim University Hospital, Norway, and Trondheim Municipal Emergency Clinic, an outpatient clinic at the hospital run by general practitioners.…”

Functional connectivity dysfunction of insular subdivisions in cognitive impairment after acute mild traumatic brain injury

“…Mild traumatic brain injury (mTBI) accounts for at least 75% of traumatic brain injury (Gardner and Yaffe 2015). Moreover, a proportion of mTBI patients frequently develop cognitive deficitis following acute mTBI and may persist for months and even years after the initial injury, thus imposes an excessive societal burden (Stenberg et al 2019). However, the underlying pathophysiology of cognitive disorders remains controversial, partly because the cognitive symptoms are not specific because these patients often perform normal neuropsychological test and lack of structural brain damage on conventional anatomical brain computer tomography (CT) and magnetic resonance imaging (MRI) (Scheibel 2017).…”