Background: Exercise during treatment is safe, reduces side-effects, and has the potential to reduce hospital length of stay. This systematic review and meta-analysis of randomized controlled trials sought to answer whether participating in an exercise intervention during chemotherapy, radiotherapy or stem cell transplant cancer treatment regimens reduced the duration and frequency of hospital admissions.
Methods: Four electronic databases (Medline, EMBASE, PEDro and Cochrane Central Registry of Randomized Controlled Trials) were systematically searched from inception until March 2023. Eligible studies included randomized controlled trials which evaluated exercise interventions implemented during chemotherapy, radiotherapy or stem cell transplant regimens compared with usual care, and which assessed hospital admissions. Study selection, data extraction, and quality assessment using the Cochrane Risk-of-Bias tool (RoB 2) were dual screened. Meta-analyses were conducted by pooling the data using random-effects models.
Results: Of 3918 screened abstracts, 20 individual studies met inclusion criteria, including 2635 participants (1383 intervention, 1252 control, 62% female, mean age=52.2±10.9 years from 18 adult studies and 11.2±3.5 years from 2 paediatric studies). Twelve studies were conducted during hematopoietic stem cell transplantation and eight during chemotherapy. Eighty percent of studies included aerobic exercise, 65% included resistance exercise, and 55% included both components. Interventions varied by dose (range: 30-70 mins/session), frequency (2-7 days/week), intensity (range: 50-80% HRmax, 12-18/20 Rate of Perceived Exertion) and duration (range: 3-52 weeks). Ninety percent of the interventions were supervised one-on-one. The dropout rate was 28% and 24% in exercise and control groups, respectively. There was a small effect size in a pooled meta-analysis that exercise during treatment reduced hospital length of stay by 1.55 days (95% CI: -2.18 to -0.92 days; standardized mean difference = -0.21, 95% CI: -0.37 to -0.04, p=0.01; n=16 studies), and a 26% lower rate of hospital admission (difference in proportions = -0.26, 95% CI: -0.42 to -0.11, p<0.01, n=5 studies). Most interventions reporting safety reported no adverse events, though adverse events were seen in two studies.
Conclusion: Exercise during treatment for cancer can decrease length of hospital stay and subsequent hospital admissions. A small effect size and high heterogeneity limits the certainty. Engaging in regular exercise may provide a critical opportunity to promote positive health behaviours early in treatment into survivorship years to mitigate the risk of developing late-effects of cancer treatment.