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15
| 3 | 2008
Klinisk Biokemi i Norden
(Fortsætter side 16)
patient’s organizations. It is recommended that the
transition will be as synchronized as possible over
the world. The ongoing discussion that laboratories
also should report an estimated average glucose value
based on the HbA1c result will be left for decision by
the clinicians.
The discrepant results for some of the methods
in the EQUALIS and Labqulity HbA1c schemes are
probably due to differences in standardization. In
Sweden some of the methods are directly calibrated
to the Mono S procedure (e.g. Tosoh), while other
methods are primarily calibrated to NGSP standards,
and the results converted to Mono S level with equa-
tions based on historical comparisons (e.g. Bio-Rad
Variant and Siemens DCA2000). As the basic tracea-
bility chains for those manufacturers now move from
NGSP to IFCC standardization, these older conver-
sion equations will no longer be valid.
It will now be interesting to follow the outcome
of the standardization in our EQA schemes during
2008 and 2009, and hopefully verify that the overall
agreement between the various HbA1c-methods will
improve.
Acknowledgement
Scheme manager Jenni Tikka, Labquality, is acknow-
ledged for providing us with data from the Labquality
HbA1c scheme.
References
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cated albumin, fructosamine and analysis of
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3. Stratton IM, Adler AI, Neil HA, Matthews
DR, Manley SE, Cull CA, et al. Association
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4. DCCT/EDIC Study Research Group. Intensive
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6. Hanberger L, Samuelsson U, Lindblad B,
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HbA1c(NGSP) HbA1c(IFCC) HbA1c(Mono S)
4.0% 20 mmol/mol
2.9%
5.0% 31 mmol/mol
4.0%
6.0% 42 mmol/mol
5.0%
7.0% 53 mmol/mol
6.1%
8.0% 64 mmol/mol
7.1%
9.0% 75 mmol/mol
8.2%
10.0% 86 mmol/mol
9.2%
Table I. Comparable numbers for NGSP, IFCC, and Mono S
standardization. The treatment goal according to ADA and
Diabetes UK is < 7% or < 53 mmol/mol and according to
EASD < 6.5% or < 48 mmol/mol. According to the Swedish
Society for Diabetology, the desirable HbA1c level for type
I diabetes is 6% HbA1c(Mono S) corresponding to 6.9%
HbA1c(NGSP) or 52 mmol/mol, and for type II diabetes 5-6%
HbA1c(MonoS) corresponding to 6.0 – 6.9 %HbA1c(NGSP) or
42 – 52 mmol/L.
