(View plain language abstract)
WCRF/AICR currently advises cancer survivors to follow the lifestyle recommendations for cancer prevention, which are presumed to be beneficial for preventing recurrence and improving survival. Though these cancer outcomes related to quantity of life are important, the quality of life (QOL) of cancer survivors is also a well-recognised patient-reported outcome to consider in cancer survivorship research.
QOL refers to the way cancer survivors perceive their health and functioning in different dimensions, including physical health, psychological well-being, level of independence, and societal participation. It is still unclear, however, whether the WCRF/AICR recommendations regarding diet, physical activity, and body composition are valid for cancer survivors and whether they apply equally to survivors of different types of cancer.
Colorectal cancer (CRC) is a prevalent type of cancer and the number of CRC survivors continues to rise. In the years post-diagnosis, CRC survivors frequently report decreased QOL and persisting cancer treatment-related problems, such as fatigue and chemotherapy-induced peripheral neuropathy (CIPN). These important patient-reported outcomes are likely to be influenced by lifestyle behaviours of CRC survivors.
Previous studies observed that poor diet quality, low physical activity level, high sedentary behaviour, and an unfavourable body composition were associated with decreased QOL and increased fatigue in CRC survivors. However, most of these studies were cross-sectional and did not look at lifestyle behaviour as a whole, which is what the WCRF/AICR recommendations aim to target.
Because many cancer survivors express the need for lifestyle advice and are open to lifestyle changes, it is important to evaluate whether adhering to the WCRF/AICR recommendations is associated over time with QOL and other relevant patient-reported outcomes, including fatigue and CIPN. Longitudinal studies are therefore highly warranted.
Hypothesis and objectives
The main objective is to test the hypothesis that adherence to the WCRF/AICR lifestyle recommendations is longitudinally associated with QOL, fatigue and CIPN as primary patient-reported outcomes in CRC survivors up to two years post-treatment.
We will analyse longitudinal associations of:
- The overall level of adherence to the WCRF/AICR recommendations
- Adherence to the individual sub-recommendations regarding diet, physical activity and body composition, with the primary patient-reported outcomes
Settings and methods
Data from the ongoing EnCoRe (Energy for life after ColoRectal cancer) study will be used. In this prospective cohort study in stage I-III CRC survivors, data is collected at 6 weeks (expected sample size N~418), 6 months (N~329), 1 year (N~276), and 2 years (N~173) post-treatment. Several patient-reported outcomes are assessed by validated questionnaires, including global QOL; physical, role, and social functioning; fatigue; and CIPN.
Dietary intake is measured by 7-day dietary records and dietary supplement use is recorded in detail. Physical activity is measured by a validated questionnaire and 7-day accelerometry. Body composition is assessed through detailed anthropometric measurements.
The potential impact of the proposed research is to provide new evidence based on high-quality prospective data for the value of the WCRF/AICR lifestyle recommendations for important patient-reported outcomes in stage I-III CRC survivors. The findings can help improve the WCRF/AICR recommendations for CRC survivors.