Cumulative effects of age and pathology on plasma carcinoembryonic antigen in an unselected elderly population.

Plasma CEA was measured in 776 institutionalized elderly patients, 593 women and 183 men, whose mean age was 80.8 +/- 9.7 yr. Of these subjects 39 were found to be free of any pathology and were considered as a control group. All the other subjects had a variety of diseases, malignant or not, known or not known to be associated with elevated CEA. This study showed that elderly people in their 80s, in apparent good health, had higher levels of CEA (3.0 +/- 1.4 ng/ml) than younger people. These levels were shown to be significantly increased in a large number of non-malignant diseases. No correlation could be found between elevated CEA values and autopsy finding or drug administration. Using the chi square test, the number of patients with CEA levels greater than 5 ng/ml was found to be significantly higher in chronic renal failure and cancer. Mortality was also found to be higher in patients with CEA levels greater than 5 ng/ml during a 25-month follow-up. Higher levels of CEA in elderly subjects in apparent good health, as well as increase of these levels in a large set of non-malignant pathology, must thus be kept in mind when interpreting data arising from old people because of both the false-positive (healthy elderly subjects) and the cumulative effects of polypathology on plasma CEA.