Laboratory results of elderly people: Forgotten aspect of laboratory medicine?

Reference values, which would be related to the individual "biological age" and which would be needed for laboratory investigations of geriatric patie nts, are at the moment not usual. Thereafter, for rational interpretation o f laboratory results, the knowledge of "preanalytical variations" is of cru cial importance. These are systematically discussed in the present contribu tion. In principle, one distinguish between "biological variations" and "pr eanalytical errors". The first are characterized by the following "factors" : "permanent" (age, genetics), "long time" (age), "intermediate" (life styl e, climate, nutrition), and "short time" (circadian, postprandial, and orth ostatic effects). The significance of "preanalytical errors" is accentuated by the fact that many of "geriatric institutions" are serviced by the labo ratories, which are not situated close to them.