We looked at the effect of exercise training on fitness level, muscle strength, quality of life, shortness of breath, tiredness, feelings of anxiety and depression, and lung function in patients with advanced lung cancer.
Patients with advanced lung cancer often have many symptoms and accompanying diseases. This, combined with side-effects of cancer treatment, leads patients to become less fit. This is concerning as fitness level is a measure of whole body health, and is critical in a patient's ability to participate in life activities and tolerate difficult treatments. Exercise training has been shown to improve fitness, muscle strength and quality of life in survivors of several types of cancers. However, the effect of exercise training on these outcomes in people with advanced lung cancer is not clear.
We looked for all research studies (randomised controlled trials) published up to July 2018. We found six studies which included 221 participants, with an average age ranging from 59 to 70 years. These studies included different numbers of people, ranging from 20 to 111.
Our results showed that, compared to those who did not exercise, people with lung cancer who did exercise were fitter and had a better quality of life. We did not find any difference in muscle strength, shortness of breath, tiredness, feelings of anxiety and depression, or lung function. No serious harms were reported in people with lung cancer who exercised, but only three studies talked about harms.
Quality of the evidence
The results of this review are not clear, mainly because of the small number of studies found, the small numbers of people in those studies, and because the studies did not seem to have been carried out to a high standard.
Exercise training may improve or avoid the decline in exercise capacity and disease-specific global HRQoL for adults with advanced lung cancer. We found no significant effects of exercise training on dyspnoea, fatigue, feelings of anxiety and depression, or lung function. The findings of this review should be viewed with caution because of the heterogeneity between studies, the small sample sizes, and the high risk of bias of included studies. Larger, high-quality RCTs are needed to confirm and expand knowledge on the effects of exercise training in this population.
Patients with advanced lung cancer have a high symptom burden, which is often complicated by coexisting conditions. These issues, combined with the indirect effects of cancer treatment, can cumulatively lead patients to continued deconditioning and low exercise capacity. This is a concern as exercise capacity is considered a measure of whole body health, and is critical in a patient's ability to participate in life activities and tolerate difficult treatments. There is evidence that exercise training improves exercise capacity and other outcomes, such as muscle force and health-related quality of life (HRQoL), in cancer survivors. However, the effectiveness of exercise training on these outcomes in people with advanced lung cancer is currently unclear.
The primary aim of this review was to investigate the effects of exercise training on exercise capacity in adults with advanced lung cancer. Exercise capacity was defined as the six-minute walk distance (6MWD; in meters) measured during a six-minute walk test (6MWT; i.e. how far an individual can walk in six minutes on a flat course), or the peak oxygen uptake (i.e. VO₂peak) measured during a maximal incremental cardiopulmonary exercise test (CPET).
The secondary aims were to determine the effects of exercise training on the force-generating capacity of peripheral muscles, disease-specific global HRQoL, physical functioning component of HRQoL, dyspnoea, fatigue, feelings of anxiety and depression, lung function, level of physical activity, adverse events, performance status, body weight and overall survival in adults with advanced lung cancer.
We searched CENTRAL, MEDLINE (via PubMed), Embase (via Ovid), CINAHL, SPORTDiscus, PEDro, and SciELO on 7 July 2018.
We included randomised controlled trials (RCTs) which compared exercise training versus no exercise training in adults with advanced lung cancer.
Two review authors independently screened the studies and selected those for inclusion. We performed meta-analyses for the following outcomes: exercise capacity, disease-specific global HRQoL, physical functioning HRQoL, dyspnoea, fatigue, feelings of anxiety and depression, and lung function (forced expiratory volume in one second (FEV1)). Two studies reported force-generating capacity of peripheral muscles, and we presented the results narratively. Limited data were available for level of physical activity, adverse events, performance status, body weight and overall survival.
We identified six RCTs, involving 221 participants. The mean age of participants ranged from 59 to 70 years; the sample size ranged from 20 to 111 participants. Overall, we found that the risk of bias in the included studies was high, and the quality of evidence for all outcomes was low.
Pooled data from four studies demonstrated that, on completion of the intervention period, exercise capacity (6MWD) was significantly higher in the intervention group than the control group (mean difference (MD) 63.33 m; 95% confidence interval (CI) 3.70 to 122.96). On completion of the intervention period, disease-specific global HRQoL was significantly better in the intervention group compared to the control group (standardised mean difference (SMD) 0.51; 95% CI 0.08 to 0.93). There was no significant difference between the intervention and control groups in physical functioning HRQoL (SMD 0.11; 95% CI -0.36 to 0.58), dyspnoea (SMD -0.27; 95% CI -0.64 to 0.10), fatigue (SMD 0.03; 95% CI -0.51 to 0.58), feelings of anxiety (MD -1.21 units on Hospital Anxiety and Depression Scale; 95% CI -5.88 to 3.45) and depression (SMD -1.26; 95% CI -4.68 to 2.17), and FEV1 (SMD 0.43; 95% CI -0.11 to 0.97).