Vol 10, No 3 (2021)
Review article
Published online: 2021-05-31

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Clinical Use and Limitation of Hemoglobin A1c Examination

Ketut Suastika1
Clin Diabetol 2021;10(3):299-306.


Haemoglobin A1c (HbA1c/A1C) is a part of haemoglobin
(Hb) that binds to glucose through non-enzymatic
reactions. In general, HbA1c is used as a parameter for
diagnosis, target therapy and monitoring or prediction
of long-term complications of diabetes mellitus
(DM) outcome. However, HbA1c can also be used to
predict the incidence of DM and vascular outcomes
in those without DM. HbA1c above 6.5% is used as
the limit for diagnosing DM, and in general, HbA1c
< 7.0% is used as the target limit of therapy in adult
DM patients. As a parameter for the diagnosis of DM
and long-term monitoring, HbA1c has limitations
and advantages over blood glucose testing, because
HbA1c is strongly influenced by several conditions
that affect the life span of erythrocytes where Hb will
remain throughout the life of the cell. Likewise, HbA1c
cannot assess the variability of blood glucose levels
short-termly and cannot determine the presence of
hypoglycaemia. With all its limitations, now HbA1c has
been established as a parameter to diagnose DM and
the most reliable parameter in predicting the incidence
of chronic complications from DM.

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