albumin creatinine ratio (ACR) and guidance when to use a renin-angiotensin system antagonist (ACEI or ARB) in CKD

Last reviewed 08/2021

NICE suggest that:

  • offer a renin-angiotensin system antagonist to people with chronic kidney disease (CKD) and:

    • diabetes and an ACR of 3 mg/mmol or more (ACR category A2 or A3)

    • hypertension and an ACR of 30 mg/mmol or more (ACR category A3)

    • an ACR of 70 mg/mmol or more (irrespective of hypertension or cardiovascular disease)

Notes:

Classification of CKD

  • CKD is classified according to estimated GFR (eGFR) and albumin:creatinine ratio (ACR), using 'G' to denote the GFR category (G1-G5, which have the same GFR thresholds as the CKD stages 1-5 recommended previously) and 'A' for the ACR category (A1-A3), for example:
    • a person with an eGFR of 25 ml/min/1.73 m2 and an ACR of 15 mg/mmol has CKD G4A2.
    • a person with an eGFR of 50 ml/min/1.73 m2 and an ACR of 35 mg/mmol has CKD G3aA3
    • an eGFR of less than 15 ml/min/1.73 m2 (GFR category G5) is referred to as kidney failure

Note that:

  • increased ACR is associated with increased risk of adverse outcomes
  • decreased GFR is associated with increased risk of adverse outcomes
  • increased ACR and decreased GFR in combination multiply the risk of adverse outcomes
GFR ( ml/min/1.73 m^2) and ACR categories and risk of adverse outcomes

A1

< 3 mg/mol (normal to mildly increased)

A2

3 -30 mg/mol (moderately increased)

A3

> 30mg/mol (severely increased)

G1

>= 90 ml/min/1.73 m^2

(Normal and High)

low risk * moderately increased risk high risk
G2

60-89 ml/min/1.73 m^2

(Mild reduction related to normal range for young adult)

low risk * moderately increased risk high risk
G3a

45-59 ml/min/1.73 m^2

(mild-moderate reduction)

moderately increased risk high risk very high risk
G3b

30-44 ml/min/1.73 m^2

(moderate-severe reduction)

high risk very high risk very high risk
G4

15-29 ml/min/1.73 m^2

(severe reduction)

very high risk very high risk very high risk
G5

< 15 ml/min/1.73 m^2

(kidney failure)

very high risk very high risk very high risk

 

ACR (albumin creatinine ratio) category

ACR (mg/mmol)

A1

<3

A2

3-30

A3

>30

Reference: