The overarching aim of this thesis has been to contribute to a better understanding of fatigue in the chronic phase of pediatric acquired brain injury (pABI). The thesis investigates secondary endpoints to a randomized controlled study (RCT), comparing two cognitive rehabilitation approaches for reducing fatigue in children and adolescents (10-17 years) with pABI after 8 weeks and 6 months; a metacognitive treatment (a pediatric version of Goal Management Training, pGMT) and a psychoeducational approach (a pediatric version of Brain health Workshop, pBHW). Parents and teachers were included in the intervention. A total of 76 participants completed the baseline assessments, and 71 participants went through with the 6 months follow-up. In three different studies, the thesis addresses the prevalence of fatigue and its associations to related domains, the effectiveness of the cognitive rehabilitation methods for reducing fatigue, and predictors of functional school outcomes after pABI.
In the first study, investigating baseline fatigue and associated factors, the findings showed that parents of the pABI survivors reported significantly more fatigue (75% of scores in clinical range; <70) compared to the healthy control group (12% of scores in clinical range). No strong associations were found between fatigue and injury characteristics, but findings indicated more fatigue girls and in the older than younger age-group for pABI participants. Network modeling revealed a central role for health-related quality of life, behavioral and executive function (EF) symptoms in relation to fatigue.
The study of the treatment effectiveness of the cognitive rehabilitation programs, demonstrated a significant reduction in parent-reported fatigue from baseline to 6 months for both pGMT and pBHW, with no significant differences between the intervention groups. However, when considering the proportion of participants that had a reliable change (RCI) in fatigue from baseline to 6 months, 40% of the total sample had a reliable change, with 26% in the pGMT-group and 54% in the pBHW-group. Higher global outcome scores and better executive attention predicted improvement in fatigue from baseline to 6 months follow-up.
In the final study, fatigue, IQ, global functioning, behavioral problems, and sex emerged as potential predictors for functional school outcomes. Of note, fatigue made the strongest unique contribution in explaining self- and parent reported quality of life in the school setting.
In conclusion, this thesis provides new insights into fatigue in children and adolescents in the chronic phase of pABI. The results suggest that fatigue is highly prevalent after pABI, and is associated with both demographic, medical, cognitive and psychological factors, as well as functional school outcomes. Both the metacognitive and psychoeducational programs show promise for reducing fatigue in pABI. There are probably several processes involved in fatigue improvement, and we have discussed some of these mechanisms pertaining to enhanced attention, psychological support, raised awareness in the children and their essential network, as well as lifestyle changes. Future research efforts should include a larger sample size with fatigue as a primary measure, emphasize the role of development in the planning of intervention studies, as well as incorporate modifiable factors associated with fatigue in the treatment programs.