SA JOURNAL OF DIABETES & VASCULAR DISEASE
VOLUME 8 NUMBER 3 • SEPTEMBER 2011
113
Diabetes Educator’s Focus
SELF-MONITORING OF BLOOD
GLUCOSE IN TYPE 2 DIABETES:
A CURRENT VIEW
S Afr J Diabetes Vasc Dis
2011:
8:
113– 116
S
elf-monitoring of blood glucose
(SMBG) is often be a daily practice
in the patient’s management of his/
her diabetes, and the readings are used
by healthcare professionals to monitor the
progress of both type 1 and type 2 diabetes
patients. In type 1 diabetes, where patients
need multiple daily injections, there is no
doubt that daily self-monitoring is essential
to manage their diabetes.
1,2
In type 2 dia-
betes, although it is often used, SMBG is a
lot more controversial. It contributes signifi-
cantly to the cost of managing the diabetes
because of the expense of the equipment
and the ongoing cost of the strips.
Healthcare budgets worldwide are under
huge pressure and healthcare professionals
must economise on the healthcare budget
where possible. It is therefore important to
knowwhether SMBG is a sensible expenditure
in the management of type 2 diabetes, partic-
ularly in non-insulin-dependent patients.
Several studies have shown no benefit
with SMBG,
3-5
whereas others suggest the
contrary.
6-8
As recently as 2008, publications
in the
British Medical Journal
(ESMON
4
and
DiGEM
5
trials) did not support the use of SMBG
in type 2 diabetes. Both trials concluded that
there was no benefit in control as measured
by HbA
1c
levels and there was a concomitant
decrease in quality of life. The conclusion was
that SMBG is not recommended in non-insu-
lin-dependent type 2 diabetics.
Many randomised, controlled trials have
been done; some supported SMBG and
others showed that it was not cost effec-
tive. Many of these studies were small in
sample size and had significant issues with
compliance with protocol. The quality of
these studies was often poor and patient
Correspondence to:
Dr Landi Lombard
Netcare Kuilsrivier Hospital,
Cape Town
Tel: +27 0(21) 900-6350
e-mail:
intervention was too infrequent, which
made the interpretation of these results
difficult. Larger meta-analyses have been
published,
9-15
which were identified from
retrospective PubMed searches, but SMBG
was done in only a third of these cases.
16
Dextrostix, used for the estimation of
blood glucose levels, was first developed in
1964
17
and was fairly inaccurate, with no
monitoring device to give readings. In the
1980s, the first blood glucose-monitoring
device was developed, and since then,
dozens of companies make these devices,
which are small and accurate and contribute
to the management of diabetes.
In South Africa, blood glucose testing con-
tributes significantly to the cost of managing
diabetes in both the private and public sectors.
However, there is no doubt that improved dia-
betes control is associated with fewer compli-
cations; and we should aim for optimal blood
glucose control. This has been supported
by large trials such as the UKPDS,
18,19
the
Kumamoto trial in type 2 diabetics,
20
and the
DCCT
1
and EDIC
21
trials in type 1 diabetes.
In a re-analysis of the DCCT
22
by Lachin
et
al
. in 2008, it was established that glycae-
mic exposure, as measured by HbA
1c
levels,
explained most of the benefits of control due
to therapy for type 1 diabetes. They could
explain 95% of the microvascular complica-
tions of retinopathy and nephropathy by the
differences in HbA
1c
levels in the two groups.
HbA
1c
levels also explained 92% of the com-
plications of peripheral neuropathy. How-
ever, HbA
1c
levels are not a good reflection of
macrovascular risk.
23
In order to assess an individual patient’s
risk of complications, HbA
1c
level is not
necessarily a good indicator of long-term
