Therapeutic exercise in cancer cachexia: exploring approaches and outcomes

Cachexia is common in patients with incurable cancer, particularly of the lung and upper-gastrointestinal tract, and impacts adversely on treatment options, morbidity, quality of life and survival. Current management of cancer cachexia is inadequate and progress is required. This thesis explores the use of exercise as a proactive supportive therapy with a focus on maintaining physical function. The first piece of work was a systematic review of the use of therapeutic exercise in patients with or cured of cancer. Across 65 exercise studies, the median [IQR] rates of uptake, adherence and completion were 63 [33–80]%, 84 [72–93]% and 87 [80–96]% respectively, with no characteristic influencing the proportion of patients taking up or completing a programme. The main reasons reported for refusal were lack of interest or the impracticality of the programme and for withdrawal were medical complication or deterioration. Overall, only about half of patients offered an exercise programme completed one. This review highlighted a need to modify existing programmes or explore novel alternatives if exercise is to be acceptable to the majority of patients. The second study explored exercise preferences in patients with incurable cancer. A questionnaire was used to determine patients’ perceived capability and preparedness to undertake six different exercise programmes, each illustrated by video clips and accompanying text, and preferences for the delivery of the most preferred programme. All 200 patients considered themselves physically capable of undertaking an exercise programme and two-thirds were prepared to undertake one at that moment in time. The most preferred type of exercise was neuromuscular electrical stimulation (NMES) 36 [35−44]%, followed by walking 22 [16−30]% and resistance training 19 [13−26]% and the majority preferred to undertake exercise at home, alone and unsupervised. This survey suggested that it is realistic to offer therapeutic exercise programmes to patients with incurable cancer and provided rationale to explore NMES in this group. The third study was a randomised controlled pilot study of NMES in patients with non-small cell lung cancer. Sixteen patients were randomised to a control group, which received usual care, or NMES group, which received daily stimulation to the quadriceps for up to 30min (frequency 50Hz, on phase 11−25%) for four weeks. All patients found the NMES device acceptable and median (range) adherence to the recommended programme was 80% (69-100). In the NMES group, quadriceps muscle strength and free-living physical activity improved by a mean of 7.4 Newton metres (22%) and 136 steps (11%) respectively, whilst exercise endurance deteriorated by a mean of 20 metres (4%). This compared favourably with the control group however none of the differences were statistically significant. These findings suggested NMES was an acceptable type of exercise and that further study is warranted in patients with lung cancer. The final piece of work was a feasibility study into the use of a lightweight ActivPAL™ monitor to measure physical activity level. The aims were to determine if this form of assessment is acceptable to patients, the optimal period of monitoring and to explore the added value of the monitor's energy expenditure (EE) estimate over a simple step count. Sixty patients with lung or upper-gastrointestinal cancer wore a monitor for one week. All but one found the monitor acceptable and mean [95% CI] adherence was 98 [94−100] %. Mean daily step count and EE values measured over 2 and 4 days were significantly higher than those from 6 days (p