Cognitive fatigue in relation to depressive symptoms after treatment for childhood cancer

Cognitive fatigue after childhood cancer is frequently overlooked despite guidelines recommending follow-up, and might be mistaken for depression due to overlapping symptoms. Our objectives were: 1) to examine ratings of fatigue in survivors of paediatric brain tumours (BT) and acute lymphoblastic leukaemia (ALL) compared to healthy controls, 2) to examine the relationship between symptoms of depression and cognitive fatigue, and 3) to evaluate parent-child concordance in ratings of cognitive fatigue.

Survivors of BT (n = 30), survivors of ALL (n = 30), and healthy controls (n = 60) aged 8-18 years completed the Pediatric Quality of Life Multidimensional Fatigue Scale and the Beck Youth Inventories. Associations between cognitive fatigue, diagnosis and depression were assessed with general linear modelling. Group differences were analysed using the Kruskal-Wallis test. Parent-child concordance was investigated with internal consistency reliability.

Cognitive fatigue was prevalent in 70% of survivors of BT survivors and in 30% of survivors of ALL. Diagnosis was the main predictor of cognitive fatigue (p < .001, η_p² = 0.178), followed by depression (p = .010, η_p² = 0.080). Survivors of BT reported significantly more fatigue than healthy controls on all fatigue subscales. While they also expressed more symptoms of depression, we found no evidence for an interaction effect. Parent-child concordance was moderate to good among survivors, but poor for controls.

Survivors of BT and ALL suffer from cognitive fatigue, with survivors of BT expressing more problems. Cognitive fatigue and depression should be assessed in survivors of childhood cancer using both self-rated and proxy-rated measures, and appropriate interventions offered.