Laboratory values in fit aging individuals - Sexagenarians through centenarians

Abstract

We determined ∼15 000 laboratory values in 236 individuals between the ages of 60 and 90 y, 22 individuals between 90 and 99 y, and 69 individuals ≥100 y, and compared these with values in young adults. We tested 47 different analytes in the 60-90-y group and 93 analytes in the ≥90-y group. Na, K, CI, and CO2 values were either identical or showed minimal change with age; pH decreased slightly. Differences in Ca values were only minor, but ionized Ca increased slightly. Phosphate decreased in men, but changed only minimally in women; parathyroid hormone increased with age. Increases with age were also observed for glucose, insulin, and C-peptide. Among the enzymes, alkaline phosphatase increased in women, but in men only >90 y; γ-glutamyltransferase increased in both sexes. Creatine kinase (CK) decreased slightly in individuals >70 y and markedly in those > 90 y of age, whereas CK-MB decreased markedly >70 y, reaching the detection limit in individuals >90 y. Lactate dehydrogenase isoenzyme 5 decreased slightly with age. Urea nitrogen increased gradually with age, but creatinine increased only in individuals ≥90 y. The increase in urea is not paralleled by a loss of protein in urine, suggesting that the possible cause of azotemia may not always be renal pathology. Urate increased in women but not in men. Liver function, as measured by total bilirubin and liver enzymes, was exceedingly well maintained. Concentrations of most proteins show little change, except for slight decreases in prealbumin, albumin, and transferrin, proteins used as an index of nutritional status. IgA values increased, IgG ranges were wider, IgM and IgD decreased, and the range for IgE was narrower than in young adults. Cholesterol, high-density lipoprotein cholesterol, and triglyceride values increased with age, but decreased in individuals ≥90 y. Among the trace elements, magnesium changed little, zinc and lead decreased, and copper values increased with age. Total triiodothyronine and thyroxine decreased, with concomitant increases in thyroid-stimulating hormone. More individuals had increased microsomal antibodies and thyroglobulin titers in the aging population than in the young. In men, the free, percent free, bioactive, and total testosterone values decreased, but luteinizing hormone (LH) and follicle-stimulating hormone (FSH) values increased. In women, estrone and estradiol values decreased, with concomitant increases in LH and FSH. Androstenedione and progesterone decreased in both sexes. Gastrin values increased with age. Blood pressure in all aging individuals was either normal or well controlled with antihypertensive drugs. Hemoglobin, hematocrit, and erythrocyte, leukocyte, and platelet counts decreased with age, as did the total serum iron.