Interpretation of laboratory results in the elderly. 1. A clinician's guide to hematologic and hepatorenal function tests.

An understanding of the normal aging process and its effects on common laboratory values is essential when evaluating the elderly patient. Although results of research to determine precise changes in values for this age-group in hemoglobin, hematocrit, white cell count, ESR, serum bilirubin and alkaline phosphatase, SGOT, and glomerular filtration have not been conclusive in most instances, some of the findings described here warrant consideration. We believe that the established normal ranges for these values do not need to be significantly modified for the elderly and that slight deviations from them are normal for the healthy patient. However, all abnormal test results should not be attributed to aging alone; the clinician might overlook the need for further diagnostic workup for possible serious disorders.