Review question
We updated the evidence about the effect of exercise training after lung surgery for non-small cell lung cancer (NSCLC) on fitness level; adverse events; quality of life; strength of the leg, hand, and breathing muscles; breathlessness; fatigue; feelings of anxiety and depression; and lung function.
Background
After lung surgery for NSCLC, people's fitness levels and quality of life decrease. We know that exercise training improves these outcomes in people with chronic lung disease and in those with prostate and breast cancer. In the 2013 version of this review, we demonstrated that exercise training improved fitness level (distance walked on the six-minute walk test) in people after lung surgery for NSCLC. Due to the limited number of studies, the effect of exercise training on quality of life and other outcomes was unclear.
Search date
The evidence is current to February 2019.
Study characteristics
We included three studies from the 2013 review and an additional five new studies from the current review, for a total of eight studies with 450 participants (180 women). The number of participants in the included studies ranged between 17 and 131; the mean age of participants was between 63 and 71 years. Six studies explored the effects of combined aerobic and strengthening exercises; one explored the effects of combined aerobic exercise and inspiratory muscle training; and one explored the effects of combined aerobic exercise, strengthening exercise inspiratory muscle training and balance training. The length of the exercise programmes ranged from four to 20 weeks, with exercises performed twice to five days a week.
Key results
Our results showed that people with NSCLC who exercised after lung surgery had better fitness level (measured using both a cycling test and the six-minute walk test) and strength in their leg muscles compared to those that did not exercise. We also showed initial evidence for better quality of life and less breathlessness in those who exercised. One adverse event (hip fracture) related to the intervention was reported in one study. The effect of exercise training after lung surgery on grip strength, fatigue, and lung function was uncertain. We found insufficient evidence for improvements in the strength of breathing muscles or feelings of anxiety and depression.
Quality of evidence
Overall the quality (certainty) of evidence for the outcomes was moderate, ranging between very low (for breathlessness) and high (for fitness level measured via the six-minute walk test).
Exercise training increased exercise capacity and quadriceps muscle force of people following lung resection for NSCLC. Our findings also suggest improvements on the physical component score of general HRQoL and decreased dyspnoea. This systematic review emphasises the importance of exercise training as part of the postoperative management of people with NSCLC.
Decreased exercise capacity and 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 prostate and breast cancer. A programme of exercise training may also confer gains in these outcomes for people following lung resection for NSCLC. This systematic review updates our 2013 systematic review.
The primary aim of this review was to determine the effects of exercise training on exercise capacity and adverse events in people following lung resection (with or without chemotherapy) for NSCLC. The secondary aims were to determine the effects of exercise training on other outcomes such as HRQoL, force-generating capacity of peripheral muscles, pressure-generating capacity of the respiratory muscles, dyspnoea and fatigue, feelings of anxiety and depression, lung function, and mortality.
We searched for additional randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2019, Issue 2 of 12), MEDLINE (via PubMed) (2013 to February 2019), Embase (via Ovid) (2013 to February 2019), SciELO (The Scientific Electronic Library Online) (2013 to February 2019), and PEDro (Physiotherapy Evidence Database) (2013 to February 2019).
We included RCTs in which participants with NSCLC who underwent lung resection were allocated to receive either exercise training, which included aerobic exercise, resistance exercise, or a combination of both, or no exercise training.
Two review authors screened the studies and identified those eligible for inclusion. We used either postintervention values (with their respective standard deviation (SD)) or mean changes (with their respective SD) in the meta-analyses that reported results as mean difference (MD). In meta-analyses that reported results as standardised mean difference (SMD), we placed studies that reported postintervention values and those that reported mean changes in separate subgroups. We assessed the certainty of evidence for each outcome by downgrading or upgrading the evidence according to GRADE criteria.
Along with the three RCTs included in the original version of this review (2013), we identified an additional five RCTs in this update, resulting in a total of eight RCTs involving 450 participants (180 (40%) females). The risk of selection bias in the included studies was low and the risk of performance bias high. Six studies explored the effects of combined aerobic and resistance training; one explored the effects of combined aerobic and inspiratory muscle training; and one explored the effects of combined aerobic, resistance, inspiratory muscle training and balance training. On completion of the intervention period, compared to the control group, exercise capacity expressed as the peak rate of oxygen uptake (VO2peak) and six-minute walk distance (6MWD) was greater in the intervention group (VO2peak: MD 2.97 mL/kg/min, 95% confidence interval (CI) 1.93 to 4.02 mL/kg/min, 4 studies, 135 participants, moderate-certainty evidence; 6MWD: MD 57 m, 95% CI 34 to 80 m, 5 studies, 182 participants, high-certainty evidence). One adverse event (hip fracture) related to the intervention was reported in one of the included studies. The intervention group also achieved greater improvements in the physical component of general HRQoL (MD 5.0 points, 95% CI 2.3 to 7.7 points, 4 studies, 208 participants, low-certainty evidence); improved force-generating capacity of the quadriceps muscle (SMD 0.75, 95% CI 0.4 to 1.1, 4 studies, 133 participants, moderate-certainty evidence); and less dyspnoea (SMD −0.43, 95% CI −0.81 to −0.05, 3 studies, 110 participants, very low-certainty evidence). We observed uncertain effects on the mental component of general HRQoL, disease-specific HRQoL, handgrip force, fatigue, and lung function. There were insufficient data to comment on the effect of exercise training on maximal inspiratory and expiratory pressures and feelings of anxiety and depression. Mortality was not reported in the included studies.