Table 4.

Association of Indices of Renal Function and Functional Capacity.

	eGFR (continuous)		Cystatin-C (continuous)		Chronic Kidney Disease
Outcome Variable	β coefficient per 1-SD decrease (95% CI)	p-value	β coefficient per 1-SD increase (95% CI)	p-value	β coefficient (95% CI)	p-value
Peak Oxygen Consumption
Unadjusted	−1.22 (−1.61, −0.83)	<0.001	−1.02 (−1.42, −0.62)	<0.001	−2.28 (−3.08, −1.49)	<0.001
Model 1*	−0.61 (−1.01, −0.22)	0.002	−0.68 (−1.06, −0.31)	<0.001	−0.88 (−1.63, −0.13)	0.02
Model 2†	−0.26 (−0.68, 0.16)	0.22	−0.30 (−0.71, 0.12)	0.16	−0.38 (−1.12, 0.36)	0.32
6-minute walk distance
Unadjusted	−27.8 (−42.5, −13.1)	<0.001	−33.7 (−48.0, −19.4)	<0.001	−51.4 (−80.9, −21.9)	<0.001
Model 1*	−5.5 (−22.4, 11.5)	0.52	−14.9 (−31.1, 1.3)	0.07	−15.5 (−47.5, 16.5)	0.34
Model 2†	−7.3 (−11.5, 26.1)	0.45	−3.2 (−21.8, 15.4)	0.73	−1.6 (−34.7, 31.6)	0.93

^*Adjusted for age, sex, exercise modality, left ventricular ejection fraction, atrial fibrillation, diabetes, hypertension, loop diuretic use, jugular venous pressure, and chronotropic index.

^†Adjusted for Model 1 variables plus hemoglobin.

eGFR = estimated glomerular filtration rate. CKD was defined as eGFR ≤60 mL/min/1.73