Exercise Linked to Better Life With Colorectal Cancer

Colorectal cancer (CRC) patients who exercised experienced an improvement in their functional capacity and quality of life (QoL) regardless of whether they exercised at home or under supervision — as long as they stuck to it, a meta-analysis suggested.

In a pooled analysis of 11 studies, six showed a supervised or mixed exercise intervention had a significant effect on CRC patients, while five showed home-based interventions just missed significance for impact (P=0.05), reported Leonardo Henrique Dalcheco Messias, MD, of the University of São Francisco in São Paulo, Brazil, and colleagues.

However, a sensitivity analysis showed significant benefit to all three types of interventions both for functional capacity and QoL among those who adhered the closest — completing 80% or more of their sessions, the authors wrote in Nature Scientific Reports.

“Such results do not necessarily imply that low physical intervention adherence for this population does not provide any benefits,” the group concluded. “However, the higher the adherence, the higher are the chances of acquiring benefits in the QoL and [functional capacity].”

Prior studies have shown the importance of physical activity not just for prevention of CRC but also reduced mortality among those who have it, with some research pointing to improved metabolism and tumor-related biomarkers as possible mechanisms.

Weighing the level of supervision needed to achieve such benefits is important, Messias’ group pointed out, because home-based intervention can “overcome common barriers reported by cancer patients, such as access, time, and cost.”

They examined qualitative data on 372 CRC patients from 11 randomized controlled trials (RTCs) across three types of exercise intervention (home-based, supervised, or mixed) who were compared to 334 CRC patients not enrolled in an exercise intervention. These RTCs were published from 2003 to 2020 and had details on the duration (6 to 16 weeks), intensity (two did not specify), and types of exercise interventions and assessed outcomes related to CRC patients’ QoL among those who had surgery or therapy.

In a quality analysis using the 10-point Physiotherapy Evidence Database (PEDro) scale, all included studies had scores that ranged from 5 to 8 (mean 6.5). Home-based intervention mean adherence was 80.2%, defined by the proportion of total sessions attended.

Overall, two studies utilized aerobic exercises, while the rest applied aerobic and resistance exercises.

Six of the studies assessed functional capacity by the 6-minute walk test or a combination of other testing protocols for peak oxygen uptake, anaerobic threshold, and cardiovascular responses, such as the heart rate, total distance covered, and time to exhaustion.

Nearly all of the studies (85%) specified the type of CRC — only two involved metastatic disease.

The authors acknowledged several limitations to the data. Mixed exercise interventions did not assess QoL. Some studies had heterogenous primary goals with a substantial variability in the frequency, length, and intensity of exercise interventions. Also, all but one study included only sedentary patients or those with low levels of physical activity. Patients with metastatic CRC were underrepresented, and 61% of the studies had a small sample size. Also, the included studies did not designate patient interventions based on tumor location (colon vs rectum).