Table 3. Multivariable linear regression for the associations between FGF23 concentrations and the best subset of FGF23 correlates, mutually adjusted for each other.

	Whole study population		Exclusion eGFR < 60 mL/min/1.73m2
Parameter	β coefficient (95% CI)	P value a	β coefficient (95% CI)	P value a
	n = 2134		n = 2061
Men	-0.21 (-0.28;-0.14)	<0.001	-0.22 (-0.30;-0.15)	<0.001
Physical activity, Q2	-0.0004 (-0.07;0.07)	0.99	-0.003 (-0.07;0.07)	0.93
Physical activity, Q3	-0.01 (-0.08;0.07)	0.89	-0.01 (-0.08;0.07)	0.89
Physical activity, Q4	0.07 (-0.01;0.15)	0.08	0.08 (-0.01;0.16)	0.07
Smokers	0.12 (0.06;0.18)	<0.001	0.12 (0.06;0.19)	<0.001
PTH, pg/mL b	0.13 (0.08;0.17)	<0.001	0.13 (0.08;0.16)	<0.001
Creatinine, mg/dL b	0.28 (0.14;0.41)	<0.001	0.27 (0.11;0.43)	0.001
Total cholesterol, mg/dL	0.001 (0.00003;0.001)	0.04	0.001 (0.0001;0.001)	0.01
HDL-cholesterol, mg/dL	-0.002 (-0.003;-0.0001)	0.06	-0.002 (-0.003;-0.0001)	0.04
C-reactive protein, mg/dL b	0.03 (0.01;0.05)	0.01	0.02 (-0.001;0.04)	0.07
Total protein intake, Q2	0.04 (-0.04;0.11)	0.37	0.02 (-0.06;0.10)	0.63
Total protein intake, Q3	-0.03 (-0.11;0.06)	0.41	-0.05 (-0.13;0.03)	0.21
Total protein intake, Q4	-0.04 (-0.12;0.05)	0.42	-0.05 (-0.15;0.04)	0.23
Calcium intake, mg/dL b	0.10 (0.03;0.18)	0.01	0.04 (-0.07;0.15)	0.45
Iron intake, mg/d b	-0.25 (-0.42;-0.08)	0.005	-0.29 (-0.47;-0.12)	0.001
Alcohol intake, g/d b	-0.02 (-0.04;-0.002)	0.03	-0.02 (-0.04;-0.001)	0.07
Energy intake, kcal/d b	0.25 (0.08;0.42)	0.003	0.21 (0.01;0.40)	0.03

eGFR stands for estimated glomerular filtration rate; Q2, Q3, Q4 stand for quartile 2, 3 and 4.

^a Based on mutual adjustment.

^b Natural log transformed.