Exercise Capacity, Muscle Strength, Respiratory Characteristics, Physical Activity and Quality of Life in Patients With Lung Cancer Awaiting Surgery

According to global cancer statistics, the most commonly diagnosing and the highest mortality rates belong to lung cancer. As known, patients with lung cancer suffer from many pathophysiological changes due to characteristics of the lung cancer and its cytotoxic treatments including chemotherapy and radiotherapy. Especially, these changes commonly occur in respiratory mechanics and gas exchange all of which resulted in pulmonary function impairment. Moreover, excessive weight loss, anemia, protein catabolism, muscle wasting, skeletal muscle atrophy and inhibition of muscle regeneration are observed in these patients in course of time.

The 6-minute walk test provides valuable and valid knowledge about exercise intolerance in diseases. As known, progressive decline in exercise capacity is commonly observed in patients with lung cancer. The loss of muscle mass also happens not only peripheral muscle but also respiratory muscles in patients with lung cancer. Based on the limited studies regarding patients with lung cancer, weakness in respiratory muscles before surgery has been demonstrated. Furthermore, these patients experience fatigue and dyspnea perceptions all of which increase disease burden and afflict quality of life.

According to the results of a study compared the patients with lung cancer before surgery and healthy individuals, the patients are less physically active than healthy individuals. Moreover, at the diagnosis stage, the patients have worse quadriceps muscle strength, nutritional status, mood and quality of life compared to others. After six months, the patients experience decreases in physical activity, 6-minute walk test distance, and muscle strength and worsening symptoms following chemotherapy, radiotherapy and/or surgery. On the other hand, it could not be clearly demonstrated in the literature to the amount of impairments of pulmonary function and respiratory muscle strength compared to healthy individuals.

To reveal aforementioned impairments in patients with lung cancer before surgery is of importance in terms of being helpful in both determining the protective rehabilitation program and also reducing the disease burden and other possible factors in lung cancer. Therefore, the aim of the current study was to investigate the differences in exercise capacity, pulmonary functions, respiratory and peripheral muscle strength, physical activity level, dyspnea, fatigue and quality of life between the patients with lung cancer before lung surgery and gender and age-matched healthy individuals.