Fatigue trajectories during pediatric ALL therapy are associated with fatigue after treatment: a national longitudinal cohort study

Objective: Fatigue is one of the most prevalent and distressing symptoms reported by survivors of childhood cancer. There is currently a lack of longitudinal studies on cancer-related fatigue, and especially on the relationship between the course of fatigue during treatment and fatigue at follow-up. The purpose of the current study was therefore to investigate if the course of fatigue during treatment, treatment intensity, serious adverse events, sex, or age at diagnosis are associated with cancer-related fatigue after treatment. Methods: Participants were 92 children and adolescents diagnosed with acute lymphoblastic leukemia (mean age at diagnosis was 6.26 years). Fatigue was measured with PedsQL multidimensional fatigue scale proxy reports 5 months after diagnosis, 12 months after diagnosis, 24 months after diagnosis, and at follow-up 12 months after end of treatment. The effect of patient and treatment characteristics on fatigue reported at follow-up was tested through logistic regression analyses. Results: The course of fatigue during treatment significantly predicted fatigue reported at follow-up for general fatigue (p =.038, OR = 9.20), sleep/rest fatigue (p =.011, OR = 15.48), and cognitive fatigue (p <.001, OR = 10.78). None of the other variables were associated with fatigue at follow-up for any of the subscales. Conclusions: The findings demonstrate that fatigue reported during treatment can predict fatigue at follow-up. These results stress the need for longitudinal assessments. Healthcare professionals need to be aware that pediatric patients who are fatigued during treatment need to receive additional attention and timely interventions since cancer-related fatigue will not resolve by itself in the first year after end of treatment.