COPD patients with exertional desaturation are at a higher risk of rapid decline in lung function.
OBJECTIVE
A recent study demonstrated that exertional desaturation is a predictor of rapid decline in lung function in patients with chronic obstructive pulmonary disease (COPD); however, the study was limited by its method used to detect exertional desaturation. The main purpose of this study was to explore whether exertional desaturation assessed using nadir oxygen saturation (SpO₂) during the 6-minute walk test (6MWT) can predict rapid lung function decline in patients with COPD.


METHODS
A retrospective analysis was performed on 57 patients with moderate to very severe COPD who underwent the 6MWT. Exertional desaturation was defined as a nadir SpO₂ of <90% during the 6MWT. Rapid decline was defined as an annual rate of decline in forced expiratory volume in 1 second (FEV₁)≥50 mL. Patients were divided into rapid decliner (n=26) and non-rapid decliner (n=31) groups.


RESULTS
A statistically significant difference in exertional desaturation was observed between rapid decliners and non-rapid decliners (17 vs. 8, p=0.003). No differences were found between the groups for age, smoking status, BODE index, and FEV₁. Multivariate analysis showed that exertional desaturation was a significant independent predictor of rapid decline in patients with COPD (relative risk, 6.8; 95% CI, 1.8 to 25.4; p=0.004).


CONCLUSIONS
This study supports that exertional desaturation is a predictor of rapid lung function decline in male patients with COPD.
Department of Pulmonary and Critical Care Medicine, Hallym University Kangdong Sacred Heart Hospital, Seoul, Korea. ; Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
Changhwan
C
Kim
Department of Pulmonary and Critical Care Medicine, Hallym University Kangdong Sacred Heart Hospital, Seoul, Korea. ; Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
Yong Bum
YB
Park
Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
So Young
SY
Park
Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
Sunghoon
S
Park
Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
Cheol-Hong
CH
Kim
Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
Sang Myeon
SM
Park
Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
Myung-Goo
MG
Lee
Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
In-Gyu
IG
Hyun
Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
Ki-Suck
KS
Jung
Lung Research Institute of Hallym University College of Medicine, Chuncheon, Korea.
Dong-Gyu
DG
Kim
D000368:Aged; D015444:Exercise / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D000860:Hypoxia / Q000175:diagnosis / Q000209:etiology; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D012129:Respiratory Function Tests; D012189:Retrospective Studies
Chronic obstructive pulmonary disease; exercise; hypoxemia; lung function