Table 4.

Covariates predicting baseline Peak VO₂ in the model

Variable	Coefficient	95% CI	P-value	Partial R2
Age	--------	--------	<0.0001 (overall)	0.13 (overall)
<=40 years	0.03	(−0.05, 0.10)
>40 years	−0.14	(−0.16, −0.13)
BMI	−0.16	(−0.18, −0.13)	<0.0001	0.07
Sex	−2.08	(−2.43, −1.72)	<0.0001	0.06
Race -White	--------	--------	<0.0001	0.06
Black or African American	−2.16	(−2.53, −1.80)
Other	−1.10	(−1.81, −0.39)
NYHA Class (III/IV vs. II)	−2.02	(−2.35, −1.69)	<0.0001	0.06
Vent. Conduction Abnormality	--------	--------	<0.0001 (overall)	0.028 (overall)
-Normal
LBBB	−0.56	(−1.03, −0.10)
RBBB	−1.62	(−2.50, −0.77)
IVCD	−1.25	(−1.75, −0.75)
Paced	−1.52	(−1.95, −1.10)
Geographic Region	--------	--------	<0.0001 (overall)	0.026 (overall)
-South USA
Northeast USA	−0.75	(−1.29, −0.21)
Midwest USA	0.49	(0.11, 0.87)
West USA	0.70	(0.15, 1.24)
Canada	−1.13	(−1.76, −0.50)
France	2.01	(0.81, 3.38)
CPX mode (bike vs. TM)	−2.45	(−3.13, −1.78)	<0.0001	0.023
Diabetes	−1.21	(−1.56, −0.87)	<0.0001	0.022
LVEF	0.07	(0.05, 0.09)	<0.0001	0.021
PAD	−1.96	(−2.59, −1.33)	<0.0001	0.017

Multiple R-Square = 0.392

Reference categories: sex = male, diabetes = non-diabetics, PAD = non-PAD, region = South USA, race = White, NYHA Class = Class II, CPX mode = treadmill, vent. conduction abnormality = normal. Abbreviations: BMI, body mass index; NYHA, New York Heart Association; Vent. conduction abnormality, ventricular conduction abnormalities; LBBB, Left bundle branch block; RBBB, Right bundle branch block; IVCD, intraventricular conduction delay; Paced, pacemaker; CPX mode (bike vs. TM), cardiopulmonary exercise testing mode (bike ergometer vs. treadmill); LVEF, left ventricular ejection fraction; PAD, peripheral arterial disease