Simple isotopic method using oral stable or radioactive tracers for estimating fractional calcium absorption in adult women
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : W. H. Lee & G. P. McCabe & B. R. Martin & C. M. Weaver
- چاپ و سال / کشور: 2010
Description
Summary We extended a simple oral method for estimating fractional calcium absorption determined by double isotopic methods using radioactive or stable isotope across wide age of adult women. Fractional calcium absorption can be estimated by using either a radioactive or stable oral isotope across the entire age spectrum of adult women. Introduction A method for estimating fractional calcium absorption using a single serum collection following a single oral radioactive isotopic tracer has been validated against a classical double isotopic tracer ratio method in adults. Our goal was to extend this simplified method to include use of stable isotopes and a broad age range. Methods We used our database of 56 observations from 26 white adult women aged 19–67 years receiving either radioactive or stable isotopes. Reference values for fractional calcium absorption were determined from 24-h double isotopic ratios in serum and urine and from full kinetic modeling. Results Equations for estimating fractional calcium absorption were developed from isotopic enrichment in serum and urine from an oral tracer andmeasures of body size using themultiple linear regression analysis. Equations using a 4- to 6-h sample following an oral dose of either a stable or radioactive isotope corrected for body size were highly correlated with the reference values for fractional calcium absorption across different aged populations (r>0.8, p<0.001). Conclusion Fractional calcium absorption can be estimated by a single oral tracer method using either radioactive or stable calcium isotopes across the entire age spectrum in healthy white adult women.
Osteoporos Int (2011) 22:1829–1834 DOI 10.1007/s00198-010-1420-1 Received: 31 March 2010 / Accepted: 15 September 2010 / Published online: 9 October 2010
