Tuesday, November 06, 2007

End stage renal disease and EGFR

Well who really gives their kidneys a thought? Patients all worry about cancer, and rightly so, and everyone is finally heeding the call to worry about their hearts. But headline news at medpagetoday.com alerts us that baby boomers are entering the age of end-stage kidney disease.

This coincident with the addition of a new lab value on routine lab printouts--EGFR. This stands for estimated glomerular filtration rate which is a fairly accurate estimate of the efficiency of kidney function. The National Kidney Foundation encourages that all persons "know their GFR number," so now we've got another number to add to our blood pressure, blood sugar, and serum cholesterol statistics. If you know your creatinine (a measure of waste in the blood included on most standard lab panels), you can know your GFR with this handy tool: EGFR calculator.

My discussions with patients about their routine lab work has, therefore, acquired a new level of complexity. The lowered thresholds for fasting blood sugar and optimal cholesterol already require extra time to interpret, but no way to explain EGFR and its implications in a sentence or two.

Results of this screening test are divided into normal (>60), and low. The things that make GFR drop are prevalent in an aging American population, and include hypertension, obesity, diabetes or even prediabetes, and the overuse of analgesics such as Tylenol and Advil. Regular use of diuretics can also contribute to diminished kidney function.

There is information that routinely passes right over the heads of most of my patients (extra weight is bad for you) and some results that finally cause them to sit up and take notice (you have diabetes). Unfortunately, 'you ought to lose weight,' when ignored for years, result in 'you have diabetes.' 'Your kidney function is low' is turning out to be an eye-opening phrase and is one best heeded while lifestyle changes can turn the trend around.


Jean said...

Again, another gem of wisdom. My Dad died of kidney failure in '05 so I'm requesting this test. Thanks again, Dr. J

Mauigirl said...

Scary stuff!

I take hydrochlorothiazide as one of my medications for high blood pressure. Being a diuretic, does this mean it may cause kidney problems for me? Maybe I should explore another medication? I am on another (Diovan) as well.

dorsey said...

Okay, I read this when you wrote it, which was six months ago. Did you honestly expect me to remember it? I think I now have the equivalent of ADD (nothing hyper about it), about to try two days on, one off of deplin, or whatever that stuff's called. (I'll give an articulate impression once I've got it working). Glad your feet are working better.