Associations of the dietary World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) recommendations with patient-reported outcomes in colorectal cancer survivors 2-10 years post-diagnosis: a cross-sectional analysis

The World Cancer Research Fund and American Institute for Cancer Research (WCRF/AICR) advise cancer survivors to follow their lifestyle recommendations for cancer prevention. Adhering to these recommendations may have beneficial effects on patient-reported outcomes after a cancer diagnosis, but evidence is scarce. We aimed to assess associations of the individual dietary WCRF/AICR recommendations regarding fruit and vegetables, fibre, fast foods, red and processed meat, sugar-sweetened drinks and alcohol consumption with patient-reported outcomes in colorectal cancer (CRC) survivors. Cross-sectional data of 150 stage I-III CRC survivors, 2-10 years post-diagnosis, were used. Dietary intake was measured by 7-d dietary records. Validated questionnaires were used to measure health-related quality of life (HRQoL), fatigue and neuropathy. Confounder-adjusted linear regression models were used to analyse associations of each WCRF/AICR dietary recommendation with patient-reported outcomes. Higher vegetable intake (per 50 g) was associated with better global QoL (beta 2 center dot 6; 95 % CI 0 center dot 6, 4 center dot 7), better physical functioning (3 center dot 3; 1 center dot 2, 5 center dot 5) and lower levels of fatigue (-4 center dot 5; -7 center dot 6, -1 center dot 4). Higher fruit and vegetables intake (per 100 g) was associated with better physical functioning (3 center dot 2; 0 center dot 8, 5 center dot 5) and higher intake of energy-dense food (per 100 kJ/100 g) with worse physical functioning (-4 center dot 2; -7 center dot 1, -1 center dot 2). No associations of dietary recommendations with neuropathy were found. These findings suggest that adhering to specific dietary WCRF/AICR recommendations is associated with better HRQoL and less fatigue in CRC survivors. Although the recommendations regarding healthy dietary habits may be beneficial for the well-being of CRC survivors, longitudinal research is warranted to gain insight into the direction of associations.