American Journal of Clinical Nutrition, Vol 57, 414-419, Copyright © 1993 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Day-to-day variation in iron-status indexes in elderly women

N Ahluwalia, CJ Lammi-Keefe, NR Haley and JL Beard
Department of Nutritional Sciences, University of Connecticut, Storrs 06269-4017.

Day-to-day variability in biochemical indicators of iron status in well- hydrated and healthy women 70-79 y old (n = 10) was determined. Venous blood was collected on 4 nonconsecutive days during a 2-wk period. Analytical (sigma 2 rep) and biological (sigma 2 fd) variance components were computed based on a previously established scheme in younger adults. These two variance components were summed to obtain the total day-to-day variability (sigma 2 fd). Our results indicate that biological variation contributed most to the intraindividual variation. We calculated that sampling once for most iron indexes and twice for plasma transferrin receptors in elderly individuals is adequate to accurately determine these indexes whereas serum iron and transferrin saturation, indexes with high CVfd, require seven and eight measurements, respectively. These data, compared with previously published data in younger adults, demonstrate that aging is associated with a decreased variation in some indexes of iron status such as serum ferritin.

This article has been cited by other articles:

				A. K Kant and B. I Graubard Ethnic and socioeconomic differences in variability in nutritional biomarkers Am. J. Clinical Nutrition, May 1, 2008; 87(5): 1464 - 1471. [Abstract] [Full Text] [PDF]

				R Stupnicki, J Malczewska, K Milde, and A C Hackney Day to day variability in the transferrin receptor/ferritin index in female athletes Br. J. Sports Med., June 1, 2003; 37(3): 267 - 269. [Abstract] [Full Text] [PDF]

				P. Suominen, K. Punnonen, A. Rajamaki, R. Majuri, V. Hanninen, and K. Irjala Automated Immunoturbidimetric Method for Measuring Serum Transferrin Receptor Clin. Chem., August 1, 1999; 45(8): 1302 - 1305. [Full Text] [PDF]