Sleep Disturbance, Depressive Symptoms, and Subsequent Quality of Life During Adjuvant Chemotherapy for Gastrointestinal Cancer

This prospective, single-center, non-interventional observational cohort study evaluated longitudinal changes in sleep quality, depressive symptoms, and health-related quality of life among adults receiving fluoropyrimidine-based adjuvant chemotherapy for nonmetastatic gastrointestinal cancers. A total of 198 participants receiving either FOLFOX or CAPEOX were enrolled at Ankara Etlik City Hospital between May 30, 2025, and March 30, 2026. Longitudinal patient-reported outcomes included the Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI), and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30). The longitudinal assessment framework included baseline, month-3, and month-6 evaluations. In addition to describing changes in sleep, depressive symptoms, and quality of life, analyses examined the temporal indirect association between baseline sleep disturbance and month-6 global health status/quality of life through month-3 depressive symptoms. Secondary analyses evaluated nutritional status, anthropometric measures, and body composition using clinically available computed tomography examinations. Treatment-regimen comparisons were observational and did not involve investigator-directed treatment assignment. The final follow-up data cutoff was September 30, 2026.