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Take the test. Understand your numbers. Talk with your doctor.
Your doctor can test your GFR by administering a creatinine blood test. Creatinine is a waste product present in your blood. If the amount of creatinine contained within a sample is too high, your kidneys' filtering ability (GFR) is likely too low. Alternatively, your doctor might administer a creatinine clearance test, which measures the amount of creatinine in both your blood and urine. Your test results are only one factor involved in calculating your GFR. Doctors also take into consideration your age, race, body size, and gender when determining the actual GFR rate. If your GFR is 90 mls/min/1.73m2 or greater, your kidneys are considered to be in good health. GFR between 60 and 89 mls/min/1.73m2 puts you into stage two chronic kidney disease (CKD). A rate between 30 and 59 mls/min/1.73m2 puts you into stage three CKD, and rate between 15 and 29 mls/min/1.73m2 are considered stage four CKD. Once your GFR dips below 15 mls/min/1.73m2, you are in stage five CKD, which means your kidneys have failed. Your doctor can provide you with additional detail regarding your GFR score and how it impacts your life. If your numbers are lower than they should be, your physician will probably recommend some type of treatment, but the specifics may vary from patient to patient. You'll need to make certain changes to your diet and overall lifestyle regardless of which stage of CKD you've entered. During the early stages, however, these changes might be enough to improve your GFR. This is especially true if you've had no prior history of kidney problems. During the later stages of CKD, your doctor will likely prescribe some form of medication to help improve your kidney function. This medication should be used alongside lifestyle changes and should not be thought of as a substitute treatment. In the final stages of CKD, your doctor will almost always put you on dialysis or recommend a kidney transplant.