Is this age-related decline in GFR or kidney disease?

I’m 82, recent GFR was 58. Same as about last 15 years. This was a fasting serum test. My eGFR does fluctuate. If I haven’t fasted, am eating sugar, etc., my serum GFR fluctuates, too.

We also have to remember that the formulae for eGFR uses age as a variable. So, no matter how good your other numbers for the formulae are, your age variable keeps your result low. It doesn’t really mean your kidneys are in danger. I tried once substituting a much younger age for the formulae, and I had to preteen I was about 30 to get a number 60 or above. This issue has been debated for a long time. Basically, if you are past a certain age, your eGFR forces a low number result. That’s been my experience.

@alicekayv
Thank you for this! You are so right. There is plenty of scholarly reporting supporting the fact that a GFR below 60 in folks over 70 does not necessarily imply kidney disease. Especially if you are stable and all other numbers are in normal range. I have been stable with gfr in the mid 50s for several years and I am 75. My doctor says this is normal and we continue to monitor.

Ask to see a nephrologist. I finally just saw one who was a lot calmer than my primary who reacts if any number is slightly too high or too low. Many people’s kidney function slows down with age. This does not automatically mean dialysis. Or that it will kill you.

Same here. I’m 82, and my highest Gfr number is the same as in my late 60s. I’ve wondered why doctors don’t call our attention to tracking that when we are much younger. I’ve fought autoimmune issues since my 20s and was never alerted to kidney issues. So I don’t even know when the number decreased. At times over the past few years, thae number go as low as 37! By paying better attention to hydration and being more aware of dietary issues, I’ve gone back the higher numbers. The factor locking me into stage 3A appears to be the age calculation factor. The ability to get back to the high 50s is suggestive of that. Somehow the eGFR doesn’t capture what is needed to do that. Fasting serum test seems to allow a correction.

Thank you! With lots of hydration and no NSAIDS and no added salt my previous reading of gfr went up to 62. But then it went back to 55. Can you share your dietary changes?

I go back tomorrow for my annual physical and who knows what the gfr will be.