RESUMO
PURPOSE: This study aimed to reveal the association of fatigue with weekly changes in the body composition in patients with nasopharyngeal carcinoma (NPC) and identified the independent strength. METHODS: Four body composition indexes and fatigue were assessed before treatment (T0, baseline) and once a week throughout radiotherapy (T1-T7). Generalized additive mixed models (GAMMs) were used to explore the trajectories and longitudinal relationships of fatigue and weekly changes in body composition. The marginal structural model (MSM) was used to control the effect of depression and anxiety. RESULTS: The trajectories of fatigue in 105 participants reached a peak in the fifth week, and changes in body composition started appearing from the second week. Four body composition indexes, weight, body mass index (BMI), body fat rate, and lean body weight loss weekly were positively associated with fatigue. High magnitude of effects was revealed when anxiety and depression were controlled as time-dependent confounders. The positive associations with fatigue were manifested in patients aged >53 years, those with senior high and above education, no drinking, >5000 Y/month of family inflow, ≥ stage III, or those receiving a dose of ≥70 Gy, ≥3 cycles of induced chemotherapy, and ≤1 cycle of concurrent chemotherapy. CONCLUSIONS: Loss of weight, BMI, body fat rate, and lean body weight could be used to independently evaluate the development of fatigue in patients with NPC during radiotherapy. Positive associations between fatigue and weekly body composition loss were found in patients with certain characteristics.
RESUMO
BACKGROUND: Patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy experience significant fatigue, which is frequently underestimated due to the lack of objective indicators for its evaluation. This study aimed to explore the longitudinal association between fatigue and nutrition status 1 week in advance. METHODS: From January 2021 to June 2022, a total of 105 NPC patients who received intensity-modulated radiation therapy were enrolled in the observational longitudinal study. The significant outcomes, including the Piper Fatigue Scale-12 (PFS-12), the Scored Patient-Generated Subjective Global Assessment (PG-SGA), four body composition indices, and the Hospital Anxiety and Depression Scale (HADS), were assessed weekly from pre-treatment until the completion of radiotherapy (T0-T7) to explore their relationship. RESULTS: The trajectories of PFS-12 and all dimensions for 105 participants reached a peak during the fifth week. Sensory fatigue consistently received the highest scores (T0 = 1.60 ± 2.20, T5 = 6.15 ± 1.57), whereas behavior fatigue exhibited the fastest increase over time (T0 = 1.11 ± 1.86, T5 = 5.47 ± 1.70). Higher PG-SGA scores were found to be weakly explainable for aggravating fatigue (ß = 0.02 ~ 0.04). Unlike generalized additive mixed models, marginal structural models (MSM) produced larger effect values (ß = 0.12 ~ 0.21). Additionally, body composition indices showed weakly negative relationships with fatigue in MSMs one week in advance. CONCLUSIONS: The PG-SGA may be a more accurate predictor of future-week fatigue than individual body composition indicators, particularly when HADS is controlled for as a time-dependent confounder.
