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Trajectory of 10-Year Neurocognitive Functioning After Moderate–Severe Traumatic Brain Injury: Early Associations and Clinical Application

Published online by Cambridge University Press:  26 February 2020

Solrun Sigurdardottir Open the ORCID record for Solrun Sigurdardottir [Opens in a new window] ,
Nada Andelic ,
Cecilie Røe  and
Anne-Kristine Schanke
Solrun Sigurdardottir*
Affiliation:
Department of Research, Sunnaas Rehabilitation Hospital, Nesoddtangen, Norway
Nada Andelic
Affiliation:
Department of Physical Medicine and Rehabilitation, Division of Clinical Neuroscience, Oslo University Hospital, Oslo, Norway Institute of Health and Society, Research Centre for Habilitation and Rehabilitation Models and Services (CHARM), Faculty of Medicine, University of Oslo, Oslo, Norway
Cecilie Røe
Affiliation:
Department of Physical Medicine and Rehabilitation, Division of Clinical Neuroscience, Oslo University Hospital, Oslo, Norway Institute of Health and Society, Research Centre for Habilitation and Rehabilitation Models and Services (CHARM), Faculty of Medicine, University of Oslo, Oslo, Norway Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Norway
Anne-Kristine Schanke
Affiliation:
Department of Research, Sunnaas Rehabilitation Hospital, Nesoddtangen, Norway
*
*Correspondence and reprint requests to: S. Sigurdardottir, PhD, Department of Research, Sunnaas Rehabilitation Hospital, Bjørnemyrveien 11, Nesoddtangen1450, Norway. Email: sosigu@ous-hf.no
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Abstract

Objective:

This study aimed to explore the 10-year trajectories of neurocognitive domains after moderate–severe traumatic brain injury (TBI), to identify factors related to long-term neurocognitive functioning, and to investigate whether performance remained stable or changed over time.

Method:

Seventy-nine patients with moderate–severe TBI between the ages of 16 and 55 years were assessed at 3 months, 1, 5, and 10 years postinjury using neuropsychological tests and functional outcomes. Three hierarchical linear models were used to investigate the relationships of domain-specific neurocognitive trajectories (Memory, Executive function, and Reasoning) with injury severity, demographics, functional outcome at 3 months (Glasgow Outcome Scale-Extended) and emotional distress at 1 year (Symptom Checklist 90-Revised).

Results:

Education, injury severity measures, functional outcome, and emotional distress were significantly associated with both Memory and Executive function. Education and emotional distress were related to Reasoning. The interaction effects between time and these predictors in predicting neurocognitive trajectories were nonsignificant. Among patients with data at 1 and 10 year follow-ups (n = 47), 94–96% exhibited stable scores on Executive function and Reasoning tasks, and 83% demonstrated stable scores on Memory tasks. Significant memory decline was presented in 11% of patients.

Conclusions:

The findings highlight the differential contribution of variables in their relationships with long-term neurocognitive functioning after moderate–severe TBI. Injury severity was important for Memory outcomes, whereas emotional distress influenced all neurocognitive domains. Reasoning (intellectual) abilities were relatively robust after TBI. While the majority of patients appeared to be cognitively stable beyond the first year, a small subset demonstrated a significant memory decline over time.

Keywords

Cognitive impairmentLongitudinalRecoveryEmotional distressRehabilitationTBI
Type
Regular Research
Information
Journal of the International Neuropsychological Society , Volume 26 , Issue 7 , August 2020 , pp. 654 - 667
Copyright
Copyright © INS. Published by Cambridge University Press, 2020

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