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 (β 2·6; 95 % CI 0·6, 4·7), better physical functioning (3·3; 1·2, 5·5) and lower levels of fatigue (−4·5; −7·6, −1·4). Higher fruit and vegetables intake (per 100 g) was associated with better physical functioning (3·2; 0·8, 5·5) and higher intake of energy-dense food (per 100 kJ/100 g) with worse physical functioning (−4·2; −7·1, −1·2). 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.

The increasing colorectal cancer (CRC) survivor population highlights the need for dietary recommendations in order to enhance health-related quality of life (HRQoL) and alleviate symptoms of fatigue, chemotherapy-induced peripheral neuropathy (CIPN), and gastrointestinal problems. Because of the therapeutic potential of dietary fiber on the gut, we aim to assess longitudinal associations of postdiagnostic dietary fiber, fruit, and vegetable intake, a major source of dietary fiber, with HRQoL, fatigue, CIPN, and gastrointestinal symptoms in CRC survivors from 6 wk to 24 mo posttreatment. In a prospective cohort among stage I–III CRC survivors (n = 459), 5 repeated study measurements between diagnosis and 24 mo posttreatment were executed. Dietary fiber intake and fruit and vegetable intake were measured by 7-d dietary records. HRQoL, fatigue, CIPN, and gastrointestinal symptoms were measured by validated questionnaires. We applied confounder-adjusted linear mixed models to analyze longitudinal associations from 6 wk until 24 mo posttreatment and used hybrid models to disentangle the overall association into intraindividual changes and interindividual differences over time. Higher dietary fiber intake and fruit and vegetable intake were longitudinally associated with statistically significant better physical functioning and less fatigue. Intraindividual analyses showed that an increase of 10 g/d in dietary fiber within individuals over time was associated with better physical functioning (β: 2.3; 95% CI: 0.1, 4.4), role functioning (ability to perform daily activities; 5.9; 1.5, 10.3), and less fatigue (−4.1; −7.7, −0.5). An average increase in fruit and vegetable intake of 100 g/d between individuals over time was predominantly associated with less fatigue (−2.2; −4.2, −0.3). No associations were found with CIPN and gastrointestinal symptoms. Our results suggest that increasing dietary fiber, fruit, and vegetable intake is related to better physical and role functioning and less fatigue in the first 2 y after the end of treatment for CRC.

Introduction: Given the growing population of colorectal cancer (CRC) survivors, identifying ways to enhance health-related quality of life (HRQoL) and alleviate complaints of fatigue and chemotherapy-induced peripheral neuropathy (CIPN) is essential. Purpose: We aimed to assess longitudinal associations of sedentary behavior (SB) and moderate to vigorous physical activity (MVPA) independently, as well as their joint association, with HRQoL, fatigue, and CIPN in CRC survivors. Methods: In a prospective cohort among stage I–stage III CRC survivors (n = 396), five repeated home visits from diagnosis up to 24 months posttreatment were executed. SB was measured using triaxial accelerometers, and MVPA, HRQoL, fatigue, and CIPN were measured by validated questionnaires. We applied confounder-adjusted linear mixed models to analyze longitudinal associations from 6 wk until 24 months posttreatment. Results: Average time in prolonged SB (accumulated in bouts of duration ≥30 min) was 5.3 ± 2.7 h·d⁻¹, and approximately 82% of survivors were classified as sufficiently active (≥150 min·wk⁻¹ of MVPA) at 6 wk posttreatment. Decreases in SB and increases in MVPA were independently associated with better HRQoL and less fatigue over time. No associations were found for CIPN complaints. A synergistic interaction was observed between prolonged SB and MVPA in affecting functioning scales. Relative to CRC survivors with low prolonged SB and high MVPA, survivors with high prolonged SB and low MVPA reported a stronger decrease in physical functioning and role functioning over time than expected based on the independent associations of prolonged SB and MVPA. Conclusion: Our longitudinal results show that less SB and more MVPA are beneficial for CRC survivors’ HRQoL and fatigue levels. Our findings regarding interaction underscore that joint recommendations to avoid prolonged sitting and accumulate MVPA are important.

Post-treatment adherence to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) lifestyle recommendations were associated with health-related quality of life (HRQoL), fatigue, and chemotherapy-induced peripheral neuropathy (CIPN) in colorectal cancer (CRC) survivors. In a prospective cohort among CRC survivors (n = 459), repeated home-visits were performed at 6 weeks, 6, 12, and 24 months post-treatment. Dietary intake, body composition, sedentary behaviour, and physical activity were assessed to construct a lifestyle score based on adherence to seven 2018 WCRF/AICR recommendations. Longitudinal associations of the lifestyle score with HRQoL, fatigue, and CIPN were analysed by confounder-adjusted linear mixed models. A higher lifestyle score was associated with better physical functioning and less activity-related fatigue, but not with CIPN. Adjustment for physical activity substantially attenuated observed associations, indicating its importance in the lifestyle score with regards to HRQoL. In contrast, adjustment for body composition and alcohol inflated observed associations, indicating that both recommendations had a counteractive influence within the lifestyle score. Our findings suggest that CRC survivors benefit from an overall adherence to the WCRF/AICR lifestyle recommendations in terms of HRQoL and fatigue, but not CIPN. Specific recommendations have a varying influence on these associations, complicating the interpretation and requiring further study.

Colorectal cancer (CRC) survivors need evidence-based guidelines pertaining to post-treatment body composition, which could benefit health-related quality of life (HRQoL). We aimed to describe the course of several body composition measures, and to assess longitudinal associations of these measures with HRQoL, fatigue and chemotherapy-induced peripheral neuropathy (CIPN). In a prospective cohort among stage I–III CRC survivors (n = 459), five repeated home visits from diagnosis up to 24 months post-treatment were executed. Body mass index (BMI), waist circumference and fat percentage were assessed as measures of adiposity, and muscle arm circumference and handgrip strength as measures of muscle mass and function. We applied linear mixed-models to describe changes in body composition over time and to analyze overall longitudinal associations. Of included participants, 44% was overweight and 31% was obese at diagnosis. All body composition measures followed similar trends, decreasing from diagnosis to 6 weeks and then increasing up to 24 months post-treatment. In confounder-adjusted mixed models, increases in adipose tissue and muscle function were longitudinally associated with better HRQoL and less fatigue, regardless of pre-treatment body composition. With regards to improving HRQoL, decreasing fatigue and CIPN, clinical practice should also focus on restoring body tissues after CRC treatment.Trial registration: NTR7099.

Fatigue is very common among colorectal cancer (CRC) patients. We examined the association between adherence to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) lifestyle recommendations and fatigue among stage I-III CRC patients, and whether inflammation mediated this association. Data from two prospective cohort studies were used. Adherence to the WCRF/AICR recommendations was expressed as a score ranging from 0–7, and assessed shortly after diagnosis. Six months post-diagnosis, fatigue was assessed with the European Organization for Research and Treatment of Cancer quality of life questionnaire C30 (EORTC QLQ-C30), and in a subpopulation, the plasma levels of inflammation markers (IL6, IL8, TNFα, and hsCRP) were assessed. Multiple linear regression analyses were performed to investigate the association between adherence to the WCRF/AICR recommendations and fatigue. To test mediation by inflammation, the PROCESS analytic tool developed by Hayes was used. A higher WCRF/AICR adherence score was associated with less fatigue six months after diagnosis (n = 1417, β −2.22, 95%CI −3.65; −0.78). In the population of analysis for the mediation analyses (n = 551), the total association between lifestyle and fatigue was (β −2.17, 95% CI −4.60; 0.25). A statistically significant indirect association via inflammation was observed (β −0.97, 95% CI −1.92; −0.21), explaining 45% of the total association between lifestyle and fatigue (−0.97/−2.17 × 100). Thus, inflammation is probably one of the underlying mechanisms linking lifestyle to fatigue.