Lung Function Decline According to Clinical Course in Nontuberculous Mycobacterial Lung Disease.
BACKGROUND
There are few data regarding the impact of nontuberculous mycobacterial lung disease (NTM-LD) on lung function during the clinical course of disease. This study aimed to assess the impact of NTM-LD on lung function decline.


METHODS
Treatment outcomes and spirometry data at diagnosis and at least three years later were obtained from 358 patients who were diagnosed with NTM-LD between January 1999 and November 2011 using the prospective NTM registry cohort. For analysis, patients were divided into three groups: those observed without treatment, those who had treatment success, and those in whom treatment failed.


RESULTS
The treatment-failure group (n = 68) had a significantly more rapid decline in FEV1and FVC compared with the observation (n = 118) and treatment-success (n = 172) groups (-52.2, -30.8, and -28.2 mL/y, respectively; P = .023 for FEV1decline; -50.4, -28.8, and -26.0 mL/y, respectively; P = .002 for FVC decline). After adjusting for confounding factors, patients with treatment failure had greater FEV1and FVC declines than did those observed without treatment (adjusted P = .026 for FEV1decline; adjusted P = .022 for FVC decline) or those treated successfully (adjusted P = .004 for FEV1decline; adjusted P = .002 for FVC decline). Patients treated successfully had declines in FEV1and FVC similar to those in the observation group.


CONCLUSIONS
The change of lung function was variable over a median 5-year follow-up period. Treatment failure was associated with a substantial decline in lung function in NTM-LD.
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Hye Yun
HY
Park
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Byeong-Ho
BH
Jeong
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Hae Ri
HR
Chon
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Kyeongman
K
Jeon
Division of Mycobacterial and Respiratory Infections, Department of Medicine, National Jewish Health, Denver, Colorado, USA.
Charles L
CL
Daley
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea. Electronic address: wjkoh@skku.edu.
Won-Jung
WJ
Koh
D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000188:drug therapy* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000188:drug therapy* / Q000503:physiopathology*; D011446:Prospective Studies; D012042:Registries; D056910:Republic of Korea; D012129:Respiratory Function Tests; D013997:Time Factors; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents
FEV; nontuberculous mycobacteria; respiratory function tests; spirometry; treatment outcome