Chronic kidney disease is more common than most people realize and, in its early stages, almost entirely quiet. The National Institutes of Health estimates that roughly one in seven adults in the United States has some form of CKD, and most do not know it. The kidneys are patient organs; they lose function gradually, and symptoms tend to appear only when a great deal of that function is already gone.
The good news is that early detection matters, and the tests that catch it are inexpensive and widely available. A person who learns about kidney disease in stage 2 or 3 has meaningful room to slow, and sometimes halt, its progression.
How kidneys are measured
Two tests do most of the work. The first is estimated glomerular filtration rate (eGFR), calculated from a blood creatinine level along with age and sex. It approximates how much blood the kidneys filter per minute. A normal eGFR is roughly 90 or above; CKD is defined as an eGFR below 60 that persists for at least three months, or evidence of kidney damage regardless of eGFR.
The second is the urine albumin-to-creatinine ratio (uACR), which measures protein leaking into the urine. Even small amounts of albumin in the urine are a signal of kidney injury and, independently, a marker of cardiovascular risk. The two tests together give a much better picture than either one alone, and current guidelines classify CKD by both.
Who should be tested? At minimum, anyone with diabetes, hypertension, cardiovascular disease, a family history of kidney disease, or a history of acute kidney injury. Older adults and people from populations with higher CKD prevalence also benefit from periodic screening.
What drives it and what slows it
The two most common causes of CKD in adults are diabetes and hypertension. Together they account for a large majority of cases. Other causes include glomerular diseases, polycystic kidney disease, obstructive uropathy, and long-term exposure to certain medications.
Slowing progression rests on a small number of well-supported interventions:
- Blood pressure control, typically to a target below 130/80, with ACE inhibitors or ARBs preferred when there is albuminuria
- Glucose control in people with diabetes, with SGLT2 inhibitors now recommended for many people with CKD regardless of diabetes status because of strong evidence for kidney protection
- Avoiding nephrotoxins where possible, including NSAIDs used regularly, and being cautious with contrast dye and certain antibiotics
- Addressing cardiovascular risk factors, because most people with CKD are far more likely to die of a cardiovascular event than to reach dialysis
Diet plays a role that is more nuanced than the old low-protein advice suggested. A registered dietitian familiar with kidney disease is worth the referral, particularly as CKD advances and potassium, phosphorus, and fluid balance become part of the equation.
What to ask your clinician
If your labs show a low eGFR or protein in the urine, useful questions include:
- Is this a stable finding or has it changed over time?
- What is my uACR, and how does it compare to previous results?
- Are any of my current medications hard on the kidneys?
- Should I be on an SGLT2 inhibitor or an ACE inhibitor / ARB?
- When should we recheck?
A single abnormal result is a prompt for a second look, not a diagnosis. Trends matter more than any one number.
Living with it
Most people with CKD will never need dialysis. The condition is manageable, and for many it becomes a background factor that shapes medication choices and periodic monitoring rather than the center of daily life. Nephrology referral is generally recommended for more advanced disease or rapidly declining function, and earlier referral is better than later when it is warranted.
The bottom line
Kidney disease is quiet until it is not, and the window when small changes make the biggest difference is the same window when there are no symptoms to prompt them. If you have risk factors, ask for an eGFR and a urine albumin test. The tests are simple. The information they give is not.