Estimating glomerular filtration rate in hypertensive subjects: Comparison of the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) Study equations

Figures & data

Figure 1. Bland–Altman plots of difference versus average of the MDRD and the CKD-EPI formulas in women and men. Solid lines show mean differences and dotted lines 95% limits of agreement. (eGFR = estimated glomerular filtration rate; CKD-EPI = Chronic Kidney Disease Epidemiology Collaboration; MDRD = Modification of Diet in Renal Disease).

Figure 2. Mean values of estimated glomerular filtration rates with 95% confidence intervals calculated by the CKD-EPI and MDRD equations by gender and age-group. (CKD-EPI = Chronic Kidney Disease Epidemiology Collaboration; MDRD = Modification of Diet in Renal Disease; eGFR = estimated glomerular filtration rate).

Figure 3. The mean ratio with 95% confidence intervals of eGFR values calculated by the CKD-EPI and MDRD equations by gender and age-group. (eGFR = estimated glomerular filtration rate; CKD-EPI = Chronic Kidney Disease Epidemiology Collaboration; MDRD = Modification of Diet in Renal Disease).

Table I. Characteristics of the subjects with no-CKD, subjects reclassified to no-CKD according to the CKD-EPI equation, and CKD according to both formulas (CKD defined).

	No-CKD n = 927	Reclassified n = 31	CKD defined n = 36	P value^a	P value^b
Female, n (%)	484 (52)	27 (87)	27 (76)	<0.001	0.36
Age, years, mean (SD)	59 (7)	62 (5)	65 (5)	0.0098	0.020
Body mass index, kg/m^2, mean (SD)	29.9 (5.0)	31.8 (5.6)	31.2 (5.9)	0.039	0.67
Blood pressure, mmHg, mean (SD)
Systolic	153 (17)	151 (19)	150 (16)	0.55	0.86
Diastolic	91 (8)	90 (10)	87 (10)	0.52	0.23
Plasma creatinine, μmol/L, mean (SD)	73.8 (12.4)	89.2 (9.8)	103.6 (13.4)	<0.001	<0.001
Plasma calcium, mmol/L, mean (SD)	1.20 (0.08)	1.20 (0.03)	1.22 (0.02)	0.84	0.087
Total cholesterol, mmol/L, mean (SD)	5.30 (0.92)	5.39 (1.01)	5.32 (0.98)	0.62	0.79
LDL cholesterol, mmol/L, mean (SD)	3.19 (0.81)	3.26 (0.76)	3.14 (0.83)	0.64	0.55
HDL cholesterol, mmol/L, mean (SD)	1.51 (0.55)	1.37 (0.49)	1.49 (0.51)	0.17	0.33
Triglycerides, mmol/L, mean (SD)	1.42 (0.73)	1.42 (0.76)	1.53 (0.71)	0.99	0.56
Glucose homeostasis				0.54	0.24
Normal, n (%)	531 (57)	18 (60)	17 (46)
Impaired glucose tolerance, n (%)	146 (16)	6 (20)	6 (16)
Impaired fasting plasma glucose, n (%)	189 (20)	6 (20)	10 (27)
Type 2 diabetes, n (%)	61 (7)	0 (0)	4 (11)
Current smoking, n (%)	138 (15)	3 (10)	4 (11)	0.61	0.91
Antihypertensive medication, n (%)
ACE inhibitors or ATR antagonists	159 (17)	4 (13)	5 (14)	0.58	0.98
Diuretics	123 (13)	9 (30)	11 (30)	0.015	0.98
Statins	127 (14)	3 (10)	6 (16)	0.78	0.72
NSAIDs	27 (3)	2 (7)	2 (5)	0.23	0.83

^aPvalue between no-CKD and reclassified groups.

^bP value between CKD defined and reclassified groups.

‘No-CKD’ defined as eGFR > 60 mL/min/1.73 m² according to both the MDRD Study and the CKD-EPI equations. ‘Reclassified’ defined as eGFR < 60 mL/min/1.73 m² according to the MDRD Study equation and eGFR > 60 mL/min/1.73 m² according to the CKD-EPI equation. ‘CKD defined’ as eGFR < 60 mL/min/1.73 m² according to both the MDRD Study and the CKD-EPI equations.

CKD = chronic kidney disease; LDL = low-density lipoprotein; HDL = high-density lipoprotein; NSAIDs = non-steroidal anti-inflammatory drugs.