As Diabetes is A Major Risk Factor for Kidney Disease. On the other hand, despite the contraindication for metformin use in diabetic patients with moderate to severe renal impairment (eGFR < 60 mL/min/1.73 m2), metformin is often used off-label in patients with moderate renal impairment.
So it is necessary to perform kidney function tests.
GFR values can be classified as follows:
Normal: 100-140 mls/min,
Mild Kidney Failure < 90 mls/min,
Moderate Kidney Failure < 60mls/min,
Severe Kidney Failure < 30 mls/min, and
End-stage Kidney Failure < 15mls/min, which is incompatible with life, without dialysis or transplantation.
An estimate of the normal value for your GFR can be obtained by using the equation: GFR = 140 – [your age]. For example, if you are a fit, healthy 30 yr old, your GFR should be approximately 110mls/min.