Hemoglobin A1c units, diagnostic limits and quality aspects updated.

Volume 4, Issue 6, December 2019     |     PP. 191-208      |     PDF (502 K)    |     Pub. Date: October 6, 2019
DOI:    243 Downloads     5830 Views  

Author(s)

Penttilä Ilkka, Kuopio Research Institute of Exercise Medicine, 70100 Kuopio, Finland
Penttilä Karri, Finnish Medicines Agency FIMEA, 70210 Kuopio, Finland
Ranta Päivi, Labquality Ltd., 00530 Helsinki, Finland
Törrönen Jukka, Kuopio Research Institute of Exercise Medicine, 70100 Kuopio, Finland
Savonen Kai, Kuopio Research Institute of Exercise Medicine, 70100 Kuopio, Finland

Abstract
In this report the use of the units, diagnostic limits and the quality aspects of hemoglobin A1c (HbA1c) were studied in worldwide clinical laboratory practice. In addition, the quality aspects were calculated for the target values from the surveys of Labquality Ltd. and ERLGH. The use of HbA1c units and the diagnostic limits for diabetes were examined using e-mail and mail inquiries to 37–51 societies of laboratory medicine (mainly clinical chemistry) from 2009 to 2019. The parametric statistical programs of Labquality Ltd. and commercial programs of SPSS® 13.0 and MS Excel 2013 (Microsoft® Co., Cambridge, MA, USA) were used.The IFCC system for HbA1c as mmol/mol unit slowly but constantly gaining acceptance in Europe, but remains quite rare outside Europe whereas the DCCT/NGSP system as a per cent unit was reduced. The mean round values of Labquality Ltd. and the corresponding values of the European Reference Laboratory for Glycohemoglobin (ERLGH) were calculated for the target values with ±6% intervals for the per cent results and ±8% intervals for the mmol/mol results. To avoid confusion, the overall use of mmol/mol unit only for HbA1c by the IFCC system could be the best one in the future.

Keywords
diabetes, HbA1c, IFCC recommendation, quality aspects, target limits

Cite this paper
Penttilä Ilkka, Penttilä Karri, Ranta Päivi, Törrönen Jukka, Savonen Kai, Hemoglobin A1c units, diagnostic limits and quality aspects updated. , SCIREA Journal of Clinical Medicine. Volume 4, Issue 6, December 2019 | PP. 191-208.

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