Influence of chronic sputum symptoms on quality of life in patients with nontuberculous mycobacterial pulmonary disease: A cross-sectional study

Background The effect of chronic sputum (CS) symptoms on health-related quality of life (HRQOL) in patients with nontuberculous mycobacterial pulmonary disease (NTM-PD) has not been studied. The aim of this study was to clarify the differences in the clinical characteristics of NTM-PD patients with and without CS and to investigate the effect of CS on HRQOL. Methods This cross-sectional study included patients with NTM-PD who were prescribed pulmonary rehabilitation at the Fukujuji Hospital from March 2016 to June 2019. HRQOL was evaluated using the MOS 36-Item Short-Form Health Survey (SF-36). Results Of the 99 subjects studied, 71 had CS (CS+) (71.7%), and 28 (28.3%) did not have CS (CS-). Patients in the CS + group had a lower body mass index, forced vital capacity percent predicted, and forced expiratory volume in 1 s percent predicted. Regarding the radiological evaluation, the proportion of patients with the fibrocavitary form and the radiological score were significantly higher in the CS + group. The mental component summary (MCS) score of the SF-36 were significantly lower in the CS + group. Multiple regression analysis showed that the presence of CS was independently associated with a lower MCS score of the SF-36. Conclusions NTM-PD patients with CS had more severe disease, with reduced pulmonary function and severe radiological findings. CS was shown to independently affect HRQOL, especially mental status.