The problem isn’t eGFR per se. The problem is the inaccurate eGFR on the lab report, which is just inversely correlated with serum creatinine.
I had to explain all this to my primary care physician when I bulked up significantly, because she was convinced I was on the verge of kidney failure, and I was like “I did some reading. Please order cystatin C.” Then you can calculate your eGFR yourself using both datapoints. My cystatin-C only eGFR is nearly 2x my creatinine-only eGFR.
eGFR: 94 as of August 2024
age 70
Male
I haven’t started rapamycin yet but would like to soon. I was using compounded rapamycin and had several blood tests, each of which showed rapamycin below measurable levels, so I consider that as “haven’t started yet”. The multiple blood tests were of variations such as putting the compounded rapamycin capsule in other types of capsules including those advertised as acid-resistant, mixing rapamycin with a penetration enhancer and applying to skin, and dissolving under tongue.
My eGFR was not previously that high. I wonder if it’s higher this year because I started taking enzymes or apple cider vinegar.
Diet: no beef or pork. I probably don’t get enough protein.
eGFR (from standard blood test) 106
age 51
sex M
Also, if care to share:
Diet Mostly lean protein / non-starch vegetables; protein+fiber forward
Rapa user? 6mg/week
[/quote]
cystatin-C 0.67 since it’s being discussed
Double check this but I think blood urea nitrogen (BUN) on your blood panel is a rough marker of protein intake. I eat nearly vegan diet, a little fish, and am also 70, but I don’t seem to have evidence of muscle loss. Probably because I exercise daily. BUN runs a bit low consistent with my diet which is clearly not high protein.
I didn’t know that, thanks for letting me know. My BUN is 15, which is within the reference range of 7-25 mg/dL. So maybe my protein intake is OK.
My glomerial filtration rate is 86 . I am 73yrs old 5’10 175lbs
I may be wrong, but from my novice understanding, and as someone with light CKD myself (IGA nephropathy), proteinuria is a more important factor in kidney decline than serum creatinine. My serum creatinine is transient and can get to negative numbers like over 1.3 (it can get much lower though, too). I think rapa might even play a role in serum creatinine temporary elevation, dont quote me there. But my proteinuria is very low, and there registers no protein or blood in urine on the general tests.
Doctors still use eGFR though