. Author manuscript; available in PMC: 2013 Jun 13.

Published in final edited form as: Am J Nephrol. 2012 Jun 13;36(1):19–26. doi: 10.1159/000339439

Table 4.

The influence of GFR versus serum Cr on prescription patterns for NSAID/COX2

Cr group	Range in GFR (ml/min/1.73 m²) Within Cr strata	Proportion prescribed NSAID/COX-2 within strata	Rate ratio (RR) of NSAID/COX2 prescription per 10 ml/min/1.73m² increase of GFR within Cr strata	p value	Predicted proportion prescribed NSAID/COX2 at specific estimates for GFR^*
Cr group	Range in GFR (ml/min/1.73 m²) Within Cr strata	Proportion prescribed NSAID/COX-2 within strata		p value	35 ml/min/1.73m²	42 ml/min/1.73m²	50 ml/min/1.73m²
≤ 1.3 mg/dl	41.1 – 59.9	21.1 %	1.07(0.89,1.16)	0.82	NA^*	0.29 (0.24, 0.36)	0.29 (0.26, 0.33)
1.4 – 1.6 mg/dl	31.8 –59.9	18.8%	1.20 (1.12,1.29)	< 0.001	0.21 (0.18,0.23)	0.23 (0.22,0.26)	0.27 (0.26,0.29)
1.7 – 2.1 mg/dl	23.5 –59.6	13.0%	1.24(1.14,1.34)	< 0.001	0.18 (0.16,0.19)	0.20 (0.19,0.22)	0.24 (0.22,0.27)
≥ 2.2 mg/dl	2.2 –43.5	8.2%	1.00 (0.95,1.06)	0.9	0.12 (0.11,0.13)	0.12 (0.10,0.14)	NA^**

Model set for patient with age less than or equal to 63, male, Caucasian, with charlson comorbidity index being 0, only index hospitalization, and no other co-morbidities.

Note: The difference in the predicted risk estimates is statistically significant for each pair of consecutive Cr categories at a fixed estimate of GFR; p values < 0.05.

^**

NA refers to no actual data at that GFR within a Cr strata.