. Author manuscript; available in PMC: 2015 Sep 2.

Published in final edited form as: Kidney Int. 2010 Oct 27;79(4):471–477. doi: 10.1038/ki.2010.431

Table 2.

Association of estimated protein intake with creatinine and cystatin C at baseline^*

	N	Not adjusted		Adjusted for GFR		Adjusted for GFR Measurement Error (0.015)		Adjusted for GFR Measurement Error (0.015), age, sex and race^**

		Coeff (SD)	p-value	Coeff (SD)	p-value	Coeff (SD)	p-value	Coeff (SD)	p-value
Serum Creatinine (%)	741	−0.141 (0.010)	<0.001	−0.006 (0.008)	0.45	0.012 (0.008)	0.145	0.024 (0.006)	<0.001

Serum Cystatin C (%)	741	−0.11 (0.009)	<0.001	−0.007 (0.006)	0.26	0.022 (0.006)	<0.001	0.009 (0.006)	0.13

Protein intake is estimated from urine urea nitrogen, cystatin and creatinine are log transformed.

^**

Interpretation: After adjustment for GFR, age, race and sex, and GFR measurement error, a 0.2 g/kg/day increase in baseline protein intake is associated with a 2.4 (0.6) % higher baseline serum creatinine and a 0.9 (0.6) % higher baseline serum cystatin C.