Aging affects every organ, and the kidneys are no exception. Understanding what normal age-related kidney changes look like helps patients and doctors make more informed decisions about monitoring and intervention.
Normal Age-Related Changes
From around age 30 to 40, kidney function begins a gradual natural decline:
- Loss of nephrons, humans are born with approximately 1 million nephrons per kidney. The number declines by roughly 1% per year after age 40.
- Reduced eGFR, average eGFR declines about 1 mL/min per year after age 40. An 80-year-old with eGFR of 60 may simply have age-related decline rather than disease.
- Reduced concentrating ability, older kidneys are less efficient at conserving water, increasing dehydration risk
- Slower drug clearance, kidney-cleared drugs remain active longer in older patients, increasing side effect risk
When Decline Becomes Disease
Age-related decline is expected. What is not expected is rapid decline, heavy proteinuria, or eGFR dropping below 45 without significant cardiovascular risk factors. Chronic kidney disease is not a normal part of aging, it is a disease process accelerated by hypertension, diabetes, obesity, and genetic factors like APOL1.
Protecting Your Kidneys as You Age
- Keep blood pressure under control, this single intervention prevents more kidney disease than any other
- Stay well hydrated, older adults are more prone to dehydration
- Use NSAIDs sparingly, ibuprofen and naproxen reduce blood flow to the kidneys
- Get regular kidney function testing after age 60, or sooner with risk factors
- Maintain a healthy weight
Learn about NuLine kidney studies or contact us with questions.