Calcemic status of geriatric patients: a longitudinal study.

Serum ionized (CaI), total (CaT) and albumin-'corrected' total (CaA) calcium concentrations were measured in 108 geriatric long-term inpatients on admission and again 37 months (mean) later. Mean CaI, especially when pH adjusted, remained extremely stable, indicating well-preserved homeostatic calcemic control even in the terminal years in the elderly. Further, the results indicate that in addition to their previously shown invalidity in interindividual comparisons, CaT and CaA are inferior to CaI and can also be misleading in the detection of slight longitudinal changes in the 'true' calcemic status of an individual geriatric patient.