Cancer cachexia is a wasting syndrome with multi-factorial pathogenesis characterized by loss of skeletal muscle mass, with or without a loss of fat mass, not fully reversed by conventional nutritional support that may lead to progressive functional impairment. The prevalence of cachexia varies with cancer type and is higher in people affected by upper gastrointestinal tract or lung cancer. Patients with cancer-related cachexia experience a progressive decline in muscle performance and endurance with a subsequent functional decline, disability in daily activities, and poor survival. In this scenario, rehabilitation aims to maintain or slow down the functional decline, thus helping people with or at risk of cancer cachexia to support their independence for longer. Exercise, in particular, may play a role inattenuating the effects of cancer cachexia, increasing muscle metabolism and insulin sensitivity and decreasing inflammation. This review investigated the effectiveness, acceptability, and safety of exercise compared with usual care, no treatment, or active control in adult patients with cancer cachexia.
This review is important for
People with cancer cachexia, their loved ones/caregivers, health professionals caring for this population, general practitioners, researchers, and policymakers.
Outcomes of this review
This is an update of an original Cochrane Systematic Review (CSR) published in 2014, which originally found no studies to include. This update included four Randomised Controlled Trials (RCTs) with 178 adult participants up to March, 2020. The outcomes analysed were lean body mass (through computed tomography, dual-energy x-ray absorptiometry scan, or bioelectrical impedance), adherence to prescribed exercise programmes, adverse events, muscle strength and endurance, exercise capacity, fatigue, and health-related quality of life.
Results showed that there was no clear evidence (very low-certainty evidence) or there were not enough data to draw any significant conclusion for any of the outcomes analysed. The downgraded evidence derived from serious study limitations, imprecision, and indirectness.
Author’s conclusion and future recommendations
The authors are uncertain about the effectiveness, acceptability, and safety of exercise for adults with cancer cachexia. Further high-quality RCTs are needed that test exercise alone or within a multimodal intervention to improve people's well-being in cancer cachexia, particularly focusing on (a) definition of cancer cachexia, (b) cancer stage, (c) randomisation, and (d) blinding.
Comment by Sara Liguori