Development of clinically significant hypoxemia over a 5-year span is associated with comorbid heart failure, PA enlargement and severe COPD exacerbation.

Researchers analyzed 678 participants with moderate-to-severe COPD recruited into the COPDGene cohort who completed baseline and 5-year follow-up visits and who were normoxic by pulse oximetry at baseline.

Forty-six participants (7%) developed resting hypoxemia at follow-up. Lower baseline oxygen saturation, self-reported heart failure, pulmonary artery (PA) enlargement on computed tomography, and prior severe COPD exacerbation were independently associated with development of resting hypoxemia.

Participants who developed hypoxemia had greater decline in 6-min walk distance and greater 5-year decline in quality of life compared to those who remained normoxic at follow-up.