Exercise as it relates to Disease/A Breath of Exercise: Feasibility of a combined exercise intervention for inoperable lung cancer patients
This is a critique of the journal article "Safety and feasibility of a combined exercise intervention for inoperable lung cancer patients undergoing chemotherapy" investigated by authors Quist, Rorth, Langer, et al. (2012).
What is the background of the research?
Lung cancer is responsible for the most cancer-related deaths globally, as well as being one of the most prevalent forms of cancers. It is predominantly caused by cigarette smoking, which accounts for more than 80% of global lung cancer incidences. Lung cancer occurs in two main forms: non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC). Often surgery cannot be performed due to the presence of co-morbidities such as emphysema and heart disease.
In the circumstance of inoperable lung cancer, it typically narrows treatment options to chemotherapy and/or radiotherapy.  Alongside the burden of disease, patients are also likely to suffer from adverse effects as a result of their treatment. Increased levels of fatigue, poor exercise tolerance, depression and anxiety are all common symptoms contributing towards a decline in physical function and quality of life. Many studies have explored the effectiveness of multi-modal exercise interventions, and have linked increasing physical activity during and after treatment reduces fatigue, increases physical capacity and improves quality of life. However, Quist et al. highlighted that very little research has investigated lung cancer patients undergoing chemotherapy, particularly with advanced lung cancer.
Where is the research from?
The Department of Oncology at the Copenhagen University Hospital within Rigshospitalet, Denmark.
What kind of research was this?
The research involved a pilot study assessing the safety and feasibility of a 6-week structured exercise intervention program in patients with inoperable lung cancer, undergoing chemotherapy. Not only was this research used to identify the practicality of a supervised exercise intervention, it also investigated the effectiveness of a home-based exercise program beyond a clinical environment. A pilot study is the initial step used to evaluate whether the research design and interventions are feasible in larger-scale studies.
What did the research involve?
The pilot study was a single-side intervention program completed by all participants who met the inclusion criteria and provided informed consent (n=29). This 6-week intervention was comprised of supervised group training sessions, accompanied with an unsupervised individual home training program.
|Inclusion Criteria||Exclusion Criteria|
|>18 years of age||Brain or bone metastases|
|Suffering either stage III or IV non-small cell lung cancer (NSCLC) or extensive disease small cell lung cancer (SCLC-ED)||Prolonged bone-marrow suppression|
|Undergoing chemotherapy treatment||Anti-coagulant treatment|
|WHO performance status of 0-2||Symptomatic heart disease; including congestive heart failure, arrhythmia, or myocardial infarction diagnosed < 3 months|
|Inability to provide consent|
Screening occurred prior to each session and assessment. Patients were excluded from the session if any of the following were present:
- Diastolic blood pressure <45 or >95
- Resting heart rate >115bpm
- Body temperature >38 degrees
- Respiratory rate >30/min
- Infection requiring treatment
- Fresh bleeding
- Low total leukocytes or platelets
- Aerobic capacity → stationary ergometer maximal power-output
- Muscle strength → 1-repetition maximum: (leg-press, chest-press, lateral pull-down, leg extension, abdominal crunch and lower back press)
- Functional capacity → 6-minute walking distance (6MWD)
- Lung capacity → forced expiration volume in 1-second (FEV-1)
- HRQOL → general and lung-specific functional assessment of cancer-related treatment (FACT-G and FACT-L) scales
|Supervised Group Training||Unsupervised Home Training|
|2 sessions weekly||3 sessions weekly|
|Warm-up: light 10-minute stationary cycle @ 60-90% heart rate maximum||Week 1-2: 20-minutes of continuous walking|
|Strength component: machine-based exercises incorporating large muscle areas. Performed in 3 series of 5-8 sets @ 70-90% 1RM.||Week 3-4: 30-minutes of continuous walking|
|Cardiovascular component: 10-15 minutes of interval training on stationary bikes @ 85-95% heart rate maximum||Week 5-6: 40-minutes of continuous walking|
|Stretching: 5-10 minutes of static stretching to cool-down||Relaxation component: 15-20 minutes of relaxation training to conclude each session|
|Relaxation component: 15-20 minutes of relaxation training to conclude||Each participant was required to complete and submit a home-training diary every week for analysis.|
What were the basic results?
Of the 29 participants who completed baseline assessment, 6 patients withdrew during the intervention due to either low motivation (n=3) or a decrease in physical performance (n=3). This left 23 patients eligible for post-intervention analysis. Group training sessions had an adherence rate of 73.3%, whereas the home-based training program had a significantly low compliance rate of 8.7%.
As hypothesized, the authors discovered statistically significant improvements in the following qualities:
- Physical capacity → increased VO2 peak
- Functional capacity → increased 6-minute walking distance
- Muscular strength → accumulative 17% increase
- Emotional well-being
What conclusions can we take from this research?
The findings of the study revealed that a 6-week combined exercise intervention is feasible for patients suffering advanced lung cancer and can enhance physical function, and emotional well-being. Due to the significantly low home training adherence rate, the authors commented further investigation is required to determine whether home training can supplement supervised exercise. The supervised training completion rate of 79% and the absence of adverse reactions reinforced the exercise intensity and modes prescribed were safe.
It is highly advised advanced lung cancer patients should participate in supervised group exercise at least twice weekly to improve their physical function and emotional well-being. Supervision will significantly reduce the likelihood of adverse reactions during exercise, the patients remain motivated, while also maintaining relatively high exercise compliance. The exercise performed should incorporate:
- Light cardiovascular warm-up
- Machine-based exercises targeting large muscle areas
- Cardiovascular training
- Relaxation training
- Lung Cancer - Wikipedia
- Lung Cancer - Cancer Council Australia
- Chemotherapy and Radiotherapy Treatment
- Benefits of Physical Activity and Exercise against Cancer
- Quist M, Rorth M, Langer S, et al. Safety and feasibility of a combined exercise intervention for inoperable lung cancer patients undergoing chemotherapy: A pilot study. Lung Cancer. 2012;75:203-208.
- Wasserman H, Bunn B. 2017. Lung Cancer Facts and Statistics. International Association for the study of Lung Cancer.
- Cancer Council [Internet]. Sydney (NSW): Cancer Council; 2018. Lung Cancer; 2018 Jul 3 [cited 2018 Sept 3]; [about 3 screens]. Available from: https://www.cancer.org.au/about-cancer/types-of-cancer/lung-cancer.html
- Timmerman R, Paulus R, Galvin J, et al. Stereostatic Body Radiation Therapy for Inoperable Early Stage Lung Cancer Patients. JAMA [Internet]. 2010 Mar 17 [cited 2018 Sept 2]; 303(11):1070-1076.
- Galvao DA, Newton RU. Review of Intervention Studies in Cancer Patients. J Clin Oncol [Internet]. 2005 Feb 1 [cited 2018 Sept 3];23(4):899-909.
- Leon AC, Davis LL, Kraemer HC. The Role and Interpretation of Pilot Studies in Clinical Research. J Psychiatr Res [Internet]. 2011 May [cited 2018 Sept 2];45(5):626-629.