RESUMO
Background@#Radiotherapy is a common treatment option for lung or esophageal cancer, particularly when surgery is not feasible for patients with poor lung function. However, radiotherapy can affect pulmonary function and thereby induce pneumonitis or pneumonia, which can be fatal in patients with respiratory impairment. The purpose of this study is to evaluate if reductions in pulmonary function after radiotherapy can be minimized through simultaneous pulmonary rehabilitation (PR). @*Methods@#In this matched case control study, we retrospectively analyzed patients who had undergone radiotherapy for thoracic malignant disease between January 2018 and June 2019. We analyzed results from pulmonary function tests and 6-minute walking tests (6MWT) conducted within the six months before and after radiotherapy treatment. @*Results@#In total, results from 144 patients were analyzed, with 11 of the patients receiving PR and radiotherapy simultaneously. Of the 133 patients in the control group, 33 were matched with 11 patients in the PR group. Changes in forced expiratory volume in one second (FEV1) and FEV1/forced vital capacity were significantly different between the PR group and the matched control group (240 mL vs. –10 mL, p=0.017 and 5.5% vs. 1.0%, p=0.038, respectively). The median distance of 6MWT in the PR group also increased significantly, from 407.5 m to 493.0 m after radiotherapy (p=0.017). @*Conclusion@#Simultaneous PR improved pulmonary function, particularly in measures of FEV1, and exercise capacity for patients with lung or esophageal cancer even after radiotherapy treatment. These findings may provide an important base of knowledge for further large population studies with long-term follow-up analysis in the identification of the PR’s effects during thoracic radiotherapy.
RESUMO
BACKGROUND: Measurement of the maximum oxygen uptake in patients with chronic obstructive pulmonary disease (COPD) has been used to determine the intensity of exercise and to estimate the patient's response to treatment during pulmonary rehabilitation. However, cardiopulmonary exercise testing is not widely available in Korea. The 6-minute walk test (6MWT) is a simple method of measuring the exercise capacity of a patient. It also provides high reliability data and it reflects the fluctuation in one's exercise capacity relatively well with using the standardized protocol. The prime objective of the present study is to develop a regression equation for estimating the peak oxygen uptake (VO2) for men with moderate to very severe COPD from the results of a 6MWT. METHODS: A total of 33 male patients with moderate to very severe COPD agreed to participate in this study. Pulmonary function testing, cardiopulmonary exercise testing and a 6MWT were performed on their first visits. The index of work (6Mwork, 6-minute walk distance [6MWD]xbody weight) was calculated for each patient. Those variables that were closely related to the peak VO2 were identified through correlation analysis. With including such variables, the equation to predict the peak VO2 was generated by the multiple linear regression method. RESULTS: The peak VO2 averaged 1,015+/-392 ml/min, and the mean 6MWD was 516+/-195 meters. The 6Mwork (r=.597) was better correlated to the peak VO2 than the 6MWD (r=.415). The other variables highly correlated with the peak VO2 were the FEV1 (r=.742), DLco (r=.734) and FVC (r=.679). The derived prediction equation was VO2 (ml/min)=(274.306xFEV1)+(36.242xDLco)+(0.007x6Mwork)-84.867. CONCLUSION: Under the circumstances when measurement of the peak VO2 is not possible, we consider the 6MWT to be a simple alternative to measuring the peak VO2. Of course, it is necessary to perform a trial on much larger scale to validate our prediction equation.