Interpretation of laboratory values in older adults.

This article describes age-related physiologic changes in the older adult and the effect of these changes, if any, on commonly ordered laboratory tests. As reported in selected research studies and literature reviews, some laboratory parameters change minimally or not at all with age, still remaining within recommended reference ranges, while others are altered with age. Misinterpretation of an abnormal laboratory value as an aging change can lead to underdiagnosis and undertreatment in some instances (such as anemia). Failure to appreciate age-related changes can lead to overdiagnosis and overtreatment in others (such as hyperglycemia). The results from ongoing national studies are needed to establish uniform older adult reference intervals.