Growing evidence supports the role of physical activity (PA) in prevention and management of colon cancer. It is important to identify optimal methods for achieving behaviour change in large-scale pragmatic trials. Here we report 1-year feasibility results for exercise behaviour change in the CHALLENGE trial.
From 2009 to 2014, 273 colon cancer survivors (high-risk stage II/III) from 42 centres across Australia and Canada were randomised to a structured exercise program (SEP; n=136) or health education materials (HEM; n=137). Primary feasibility outcome in pre-specified interim analysis was difference between groups of ≥5 metabolic equivalent task (MET)-hours/week in recreational PA after 250 participants reached 1-year follow-up. Secondary outcomes included health-related fitness.
The SEP group reported an increase in recreational PA of 15.6 MET hours/week compared with 5.1 MET-hours/week in the HEM group [mean difference +10.5; 95%CI= +3.1 to +17.9; P=0.0002]. The SEP group also improved relative to HEM group in 6-minute walk (P< 0.0001), 30-second chair stand (P<0.001), 8-foot up-and-go (P=0.004), sit-and-reach (P=0.08) and predicted VO2max (P=0.068).
The CHALLENGE trial continues to accrue internationally, with additional sites opened in USA, France, South Korea, Israel, United Kingdom. Australia has 24 sites across five states, with 158 patients randomised. Internationally, the trial has accrued 468 participants of planned 962. The study involves teams of exercise physiologists/physiotherapists working with oncologists and Clinical Trials coordinators.
The behaviour change intervention in the CHALLENGE Trial produced a substantial increase in self-reported recreational PA that met the feasibility criterion for trial continuation. Objective improvements in fitness are consistent with PA levels associated with improved colon cancer outcomes in observational studies. These interim data indicate that the CHALLENGE trial is poised to determine the causal effects of PA on colon cancer outcomes. It is important to complete recruitment to this innovative trial.