B. KIDNEY HEALTH TESTS
4. eGFR (Estimated Glomerular Filtration Rate)
What it measures: eGFR is calculated from a blood creatinine level (along with age, sex, and sometimes race/body size) and estimates how well the kidneys are filtering waste from the blood, expressed as mL/min/1.73m².
Why it's needed: Diabetes is one of the leading causes of chronic kidney disease worldwide, and kidney damage often develops silently with no symptoms until it is advanced. eGFR is essential both for catching kidney decline early and for safely dosing many diabetes medications (metformin, several DPP-4 inhibitors, SGLT2 inhibitors, and insulin all require dose adjustment as kidney function changes).
How often: At least once a year for most people with diabetes; more frequently (every 3 to 6 months, or as directed) if eGFR is already reduced, if albuminuria (see below) is present, or after starting/adjusting a medication that affects the kidneys.
5. UACR (Urine Albumin-to-Creatinine Ratio)
What it measures: UACR checks for small amounts of the protein albumin leaking into the urine — a sign that the kidney's filtering units (glomeruli) are being damaged, often before eGFR itself drops. It is measured on a spot urine sample, not a full 24-hour collection, and is generally a more sensitive early-warning test than eGFR alone.
Why it's needed: Because early diabetic kidney disease often produces no symptoms and can be reversed or slowed if caught early with the right medications (such as ACE inhibitors, ARBs, SGLT2 inhibitors, or nonsteroidal MRAs), catching albuminuria early meaningfully changes what treatment is offered and can protect long-term kidney and cardiovascular health.
How often: At least once a year for everyone with diabetes, alongside eGFR; more often if already abnormal or if kidney-protective medication has recently been started or adjusted.