Peripheral muscle strength, dyspnea, and pulmonary function are predictors of incremental shuttle walk test distance in patients with non-tuberculous mycobacterial pulmonary disease

Abstract

Background: Patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD) have impaired exercise capacity and health-related quality of life (HRQOL). However, the factors that influence the reduction in exercise capacity are unclear. We investigated the associations between exercise capacity and clinical variables and predictors of exercise capacity.

Methods: In total, 150 patients with NTM-PD participated in the study. We assessed incremental shuttle walk test (ISWT), peripheral muscle strength, body mass index (BMI), disease duration, pulmonary function, dyspnea and HRQOL.

Results: The mean ISWT distance (ISWD) was 443 m. A univariate analysis showed a significant correlation between ISWD and BMI, pulmonary function, handgrip force, age, disease duration, dyspnea, and HRQOL. A multiple regression analysis showed that ISWD was significantly associated with age, pulmonary function, handgrip force, and dyspnea.

Conclusions: The present study is the first to identify the relationship between ISWD and clinical variables and predictors of ISWD in patients with NTM-PD.