ABSTRACT Background: Chronic obstructive pulmonary disease (COPD) is associated with reduced physical function and quality of life and has a substantial impact on employment. In Japan, employment rates among patients with COPD are particularly low. Although airflow limitation and comorbidities have been linked to employment status, the role of exercise tolerance remains unclear. Objectives: This study aimed to investigate the characteristics of working men with stable COPD and to identify factors associated with employment status, with a focus on exercise tolerance. Methods: A total of 240 men with stable COPD were included in this cross-sectional study. The measurements included respiratory function, grip strength, knee extension strength, peripheral oxygen saturation, pulse rate (PR), degree of dyspnea (chest), and lower limb fatigue (leg) during the 6-min walk test (6MWT), respiratory rate, 6-min walk distance (6MWD), and Nagasaki University Respiratory Disease ADL Questionnaire. Independent two-sample tests, multivariate logistic regression analysis, and receiver-operating characteristic analysis were used to examine the relationship between employment status and each indicator, with a significance level set at 5%. Results: The analysis included 20 and 115 individuals from the working and nonworking groups, respectively. Propensity score matching was performed with age as a covariate, resulting in the selection of 20 individuals from the nonworking group. The working group showed significantly higher values than the nonworking group in forced expiratory volume in 1 s (FEV1.0) ( P = 0.037), FEV1.0% (P = 0.05), %FEV1.0 ( P = 0.035), maximum PR during the 6MWT (PR max; P = 0.005), and 6MWD ( P = 0.016). In addition, the 6MWD was identified as a factor associated with employment status (odds ratio = 1.007, confidence interval: 1.001–1.013, P = 0.023). Moreover, the area under the curve was 0.73 ( P = 0.013), and the cutoff value for the 6MWD was 224.5 m. Conclusion: The study suggests that the 6MWD is associated with employment status in men with COPD.
Yamazaki et al. (Thu,) studied this question.