Cancer Epidemiol Biomarkers Prev. 2020 Apr 3. Epub 2020 Apr 3. PMID: 32245785
Higher serum vitamin D concentrations are longitudinally associated with better global quality of life and less fatigue in colorectal cancer survivors up to 2 years after treatment.
BACKGROUND: Vitamin D status may be an important determinant of health-related quality of life of colorectal cancer (CRC) survivors. The current study investigated longitudinal associations between serum 25-hydroxyvitamin D3 (25OHD3) concentrations and quality of life in stage I-III CRC survivors up to 2 years post-treatment.METHODS: CRC patients (n=261) were included upon diagnosis. Home visits (including blood sampling) were performed at diagnosis and at 6 weeks, 6 months, 1 and 2 years post-treatment. Serum 25OHD3 concentrations were measured using liquid chromatography-tandem mass spectrometry and adjusted for season. Validated questionnaires were used to assess global quality of life and cognitive functioning (EORTC-QLQ-C30), fatigue (EORTC-QLQ-C30 and Checklist Individual Strength, CIS), and depression and anxiety (Hospital Anxiety and Depression Scale). Statistical analyses were performed using linear mixed-models and adjusted for sex, age, time since diagnosis, therapy, comorbidities, physical activity, and BMI.RESULTS: At diagnosis, 45% of patients were vitamin D deficient (