Your Lab Results Decoded

How’s your bilirubin level? And your BUN/creatinine ratio? Unless you enjoy reading Dictionary of Medical Terms, your routine lab results can seem downright cryptic. To help you decipher them, we asked Mark S. Lachs, M.D., author of  Treat Me, Not My Age, and Marie  A. Bernard, M.D., deputy director of the National Institute on Aging, to explain what all those numbers really mean.

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Just be aware: Abnormal test results are fairly common, especially among older adults. “Fifty-plus folks tend to take more medications,” says Lachs, “and that can throw off test results. For example, diuretics can alter sodium and potassium levels; heparin can decrease your platelet count.” (These are real abnormalities that may need further treatment.) Plus, many older adults have chronic conditions that require more frequent testing — and the more you’re tested, the greater the likelihood of error. Finally, normal ranges are based on population averages, so normal for you might be slightly out of that range and of no significance. For instance, if you have Gilbert’s syndrome, a common, mild liver condition, you’d show elevated bilirubin, which could otherwise signal a serious liver dysfunction. “If you have known abnormalities, be sure to remind your doctor each time you get tested,” says Lachs.  

It’s a good idea to schedule a doctor’s appointment after undergoing lab work. That way, you can discuss any unusual results face-to-face. … Back to Article