Table 3.

Association between Continuous Decline in Cardiorespiratory Fitness (Yr 0 To Yr 20) and Annualized Decline in Lung Health from Peak Measurement to Year 20

	Model 1		Model 2
	β (95% CI)	P Value	β (95% CI)	P Value
Decline* FEV1, ml/yr	2.54 (2.18 to 2.90)	<0.001	1.95 (1.54 to 2.36)	<0.001
Decline* FVC, ml/yr	3.27 (2.82 to 3.72)	<0.001	2.08 (1.56 to 2.58)	<0.001
Decline* FEV1/FVC, %/yr	0.12 (−0.51 to 0.60)	0.78	1.0 (0.42 to 1.6)	0.002

Definition of abbreviation: CI = confidence interval.

Values shown are per minute decline in treadmill duration between Year 0 and Year 20 (a positive coefficient indicates that greater decline in fitness is associated with greater decline in lung function). Model 1 covariates: age, race-sex group, height, center, peak lung function, Year 0 treadmill duration, years from peak lung function to Year 20. Model 2 covariates: model 1 + body mass index (Yr 0), change in body mass index (Yr 0 to Yr 20), lifetime pack-years smoked (Yr 20).

^*Decline is defined as peak minus Year 20 lung function such that a positive number denotes a greater decline in lung function and a negative number denotes less decline.