| pubmed-article:21183609 | pubmed:abstractText | The current debate about the lower limit of normal (LLN) vs the 0.7 fixed ratio to diagnose COPD is not completely resolved, and little information about the clinical impact of these different criteria is available. We compared differences in health-related quality of life, exacerbations, exercise tolerance, physical activity, comorbidity, and systemic biomarkers of subjects with FEV(1)/FVC < 0.7 but > LLN (ratio-only group) vs subjects without COPD and those with mild or moderate to severe COPD. | lld:pubmed |
