Health-related quality of life associates with change in FEV1 in COPD: results from the COSYCONET cohort

Table 5 Cross-sectional and longitudinal estimates for the association between FEV₁ and generic HRQL as measured with the EQ VAS

*Outcome: EQ VAS*	Total sample	GOLD 1/2	GOLD 3/4
	estimate [95% CI]	estimate [95% CI]	estimate [95% CI]
FEV₁ between-subjects	1.08* [0.95 to 1.21]	0.71* [0.49 to 0.93]	1.20* [0.83 to 1.58]
FEV₁ within-subjects	−0.87* [− 1.13 to − 0.62]	−0.67* [− 0.98 to − 0.35]	−1.20* [− 1.64 to − 0.76]

*p < 0.001
Hierarchical linear models (HLM) adjusted for age, sex, BMI, education, smoking status, number of comorbidities, and exacerbation history
Interpretation: Positive estimates indicate improvement in HRQL. FEV₁ between-subjects: cross-sectional difference in HRQL per 100 ml difference in FEV₁ between subjects. FEV₁ within-subjects: longitudinal change in HRQL per 100 ml decrease in FEV₁ within subjects over time

ISSN: 1471-2466