Associations Between Exercise, Quality of Life, and Fatigue in Colorectal Cancer Survivors

Abstract
This study was designed to examine quality of life and fatigue in colorectal cancer survivors meeting and not meeting public health exercise guidelines. A Canadian provincial cancer registry identified colorectal cancer survivors who were mailed a questionnaire that assessed self-reported exercise, quality of life (Functional Assessment of Cancer Therapy - Colorectal), fatigue, medical, and demographic variables. Completed questionnaires were received from 413 (61.3 percent) eligible colorectal cancer survivors. Only 25.9 percent of colorectal cancer survivors reported meeting exercise guidelines. Colorectal cancer survivors meeting public health exercise guidelines reported clinically and significantly better quality of life (mean difference, 6; 95 percent confidence interval, 2.3-9.8; P = 0.002) and fatigue (mean difference = 5.2; 95 percent confidence interval, 2.9-7.5; P < 0.001). Differences remained after adjusting for medical and demographic factors. Cancer site (i.e., colon vs. rectal) was the only variable to moderate this association (P < 0.05 for interaction). Colorectal cancer survivors meeting public health exercise guidelines reported significantly and meaningfully better quality of life and fatigue scores than colorectal cancer survivors who did not meet guidelines. Prospective observational studies and randomized, controlled trials are needed to further assess the causal nature of these relationships.