After lung surgery for non-small cell lung cancer (NSCLC), people are less able to exercise and have worse health-related quality of life (HRQoL). Exercise training has been shown to be effective at improving both exercise capacity and HRQoL in people with some chronic lung diseases, such as emphysema and chronic bronchitis, as well as in those with prostate and breast cancer. However, the effects of exercise training in people following lung surgery for NSCLC are unclear.
This review included data from 178 participants in three studies. The overall quality of evidence was poor because of the small number of studies eligible for inclusion as well as limitations in their methodology. Results from our review showed that, after exercise training, exercise capacity was significantly higher in the intervention group compared to the control group (people who did not receive exercise training). However, this review did not show improvements in HRQoL, lung function or the strength of the leg muscles.
Exercise training may improve the exercise capacity of people following lung surgery for NSCLC.
The evidence summarised in our review suggests that exercise training may potentially increase the exercise capacity of people following lung resection for NSCLC. The findings of our systematic review should be interpreted with caution due to disparities between the studies, methodological limitations, some significant risks of bias and small sample sizes. This systematic review emphasises the need for larger RCTs.
Decreased exercise capacity and impairments in health-related quality of life (HRQoL) are common in people following lung resection for non-small cell lung cancer (NSCLC). Exercise training has been demonstrated to confer gains in exercise capacity and HRQoL for people with a range of chronic conditions, including chronic obstructive pulmonary disease and heart failure, as well as in people with cancers such as prostate and breast cancer. A programme of exercise training for people following lung resection for NSCLC may confer important gains in these outcomes. To date, evidence of its efficacy in this population is unclear.
The primary aim of this study was to determine the effects of exercise training on exercise capacity in people following lung resection (with or without chemotherapy) for NSCLC. The secondary aims were to determine the effects on other outcomes such as HRQoL, lung function (forced expiratory volume in one second (FEV1)), peripheral muscle force, dyspnoea and fatigue as well as feelings of anxiety and depression.
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 2 of 12), MEDLINE (via PubMed) (1966 to February 2013), EMBASE (via Ovid) (1974 to February 2013), SciELO (The Scientific Electronic Library Online) (1978 to February 2013) as well as PEDro (Physiotherapy Evidence Database) (1980 to February 2013).
We included randomised controlled trials (RCTs) in which study participants with NSCLC, who had recently undergone lung resection, were allocated to receive either exercise training or no exercise training.
Two review authors screened the studies and identified those for inclusion. Meta-analyses were performed using post-intervention data for those studies in which no differences were reported between the exercise and control group either: (i) prior to lung resection, or (ii) following lung resection but prior to the commencement of the intervention period. Although two studies reported measures of quadriceps force on completion of the intervention period, meta-analysis was not performed on this outcome as one of the two studies demonstrated significant differences between the exercise and control group at baseline (following lung resection).
We identified three RCTs involving 178 participants. Three out of the seven domains included in the Cochrane Collaboration's 'seven evidence-based domains' table were identical in their assessment across the three studies (random sequence generation, allocation concealment and blinding of participants and personnel). The domain which had the greatest variation was ‘blinding of outcome assessment’ where one study was rated at low risk of bias, one at unclear risk of bias and the remaining one at high risk of bias. On completion of the intervention period, exercise capacity as measured by the six-minute walk distance was statistically greater in the intervention group compared to the control group (mean difference (MD) 50.4 m; 95% confidence interval (CI) 15.4 to 85.2 m). No between-group differences were observed in HRQoL (standardised mean difference (SMD) 0.17; 95% CI -0.16 to 0.49) or FEV1 (MD -0.13 L; 95% CI -0.36 to 0.11 L). Differences in quadriceps force were not demonstrated on completion of the intervention period.