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VOLUME 8 NUMBER 3 • SEPTEMBER 2011
ADA WATCH
SA JOURNAL OF DIABETES & VASCULAR DISEASE
tion of the study insulins in this prospective,
multi-centre, open-label study of insulin
analogues, run by Novo Nordisk.
The A
1
chieve study is aimed at evaluating
effectiveness and adverse events of premix
(biphasic insulin) and mealtime (insulin
aspart) insulin analogues in routine clini-
cal-practice treatment of type 2 diabetes.
In the baseline data, up to 75% of par-
ticipants enlisted had cardiovascular disease.
Up to 84% had other diabetic complica-
tions, such as kidney disease, retinopathy,
foot ulcers and neuropathy.
At the time of study entry, around 9% of
patients had not received any glucose-low-
ering medication despite their HbA
1c
levels
being above 10%. Those on oral antidi-
abetic medication had duration of diabetes
of 5.9 years in South Asia and 10.4 years in
Latin America.
Despite their poor glucose control, they
were not yet receiving insulin therapy.
Prof Phillip Home, Professor of Diabetes
Medicine in Newcastle, UK noted that this
indicates the often-experienced delay of ini-
tiating insulin therapy.
These baseline data from developing
environments contrast with the UKPDS
(49) study, which has shown that by six
years’ duration of type 2 diabetes, 50% of
patients should be on insulin therapy to keep
HbA
1c
levels within the 7% target range.
Source: A
1
CHIEVE study baseline data, ADA congress
2011.
SOUTH AFRICAN CONTRIBUTIONS
NAVIGATOR trial provides clinical
setting predictors for type 2 diabe-
tes, including black patients
The NAVIGATOR trial results of patients
with impaired glucose tolerance (IGT) and
cardiovascular disease (CVD) (or risk fac-
tors for CVD) were evaluated to determine
hazard ratios for later development of type
2 diabetes (T2DM). In the NAVIGATOR study
over a five-year period, 35% of patients
developed type 2 diabetes.
In this guided audio-tour poster, the
only South African poster in this section, Dr
Naomi Levitt and her co-workers’ contribu-
tion to this study is noted.
Baseline data from the NAVIGATOR trial
were used to develop a multivariate Cox
proportional hazards model to estimate the
risk of developing type 2 diabetes. Factors
included were age, region, race, family his-
tory of T2DM, prior history of CVD, BMI,
systolic blood pressure, and fasting glucose/
two-hour glucose, HbA
1c
and platelet/B
haemoglobin levels.
These factors provided better predictive
value at the determined hazard ratio than
other available international models such as
the San Antonio Heart Study model and the
FINRISK score. The value of the NAVIGATOR
model is that it uses variables available in
an everyday clinical setting and can be used
globally to estimate future risk of type 2
diabetes in high-risk populations, including
black/African communities.
Source: Abstract No 1301 – poster. Estimating diabetes
risk in patients with IGT and CVD or risk factors for CVD.
ADA 2011 congress.
CDE study sheds additional light on
diabetic retinopathy risk in African
patients
In this extensive database of 5 565 patients
attending the CDE Centre in Johannesburg,
who underwent diabetic retinopathy assess-
ment using a Canon non-mydriate camera
without mydriasis, the majority (70%) had
no diabetic retinopathy.
Those with diabetic retinopathy were
more likely to be of non-white ethnicity
(33.9 vs 26.3%), and hypertensives using
ACE inhibitors, with fewer on aspirin.
The presence of diabetic retinopathy was
independently associated with increased
duration of diabetes, non-white ethnicity
[indigenous African 1.4 ocular risk com-
pared to Caucasians (1), Asians (1.6) and
mixed-race ancestry (3.3)].
This study emphasises the importance
of the evaluation of diabetic retinopathy in
vulnerable African, Asian and mixed-race
patients in South Africa.
Source: Abstract 2138 – poster. Chowdhury SR, Thomas
RL, Distiller L, Brown V, Kramer BD, Luzio SD, Owens DR.
ADA 2011 congress.
Identifying patients at high risk of
sight-threatening diabetic retinopa-
thy: the CDE database (2001–2009)
Increased duration of diabetes, a higher
HbA
1c
level at presentation to the centre
and mixed-race ethnicity, were independ-
ently associated with the development
of sight-threatening diabetic retinopathy
(STDR). Over the eight-year period, 12%
of the more than 5 000 patients devel-
oped background diabetic retinopathy,
1.2% developed STDR and only one subject
developed proliferative diabetic retino-
pathy.
This centre ensures annual diabetic retin-
opathy screening as a standard feature of its
diabetes care. In less well-resourced clinics,
the identification of patients at higher risk of
diabetic retinopathy can help to ensure that
these vulnerable patients receive additional
care, education, and efforts to improve dia-
betes control to reduce microvascular com-
plications.
Source: Abstract No 2134 – poster. Thomas RL,
Chowdhury SR, Distiller LA,
et al
. Development of
diabetic retinopathy in subjects attending a diabetes and
endocrinology clinic in Johannesburg, South Africa.
TG/HDL-C ratio fails to identify insu-
lin resistance in overweight black
women worldwide
In this interesting study of insulin resistance
in overweight women of African descent
from South Africa, West Africa (Jamaica)
and America, the value of the triglyceride/
high-density lipoprotein cholesterol (TG/
HDL-C) ratio was assessed as a tool to iden-
tify insulin resistance.
Contrasting the correlative value of
this ratio in white South African women,
the ratio was shown to be predictive in all
women when the BMI was less than 25 kg/
m
2
. However when the BMI was above this
level, the TG/HDL-C did not correlate with
HOMA-IR in African women whether they
were African-American, South African or
West African. It did however still retain its
ability to identify white women with insulin
resistance, irrespective of their being over-
weight.
There is a need to develop an alternative
diagnostic tool that can be correlated with
insulin resistance in overweight African
women worldwide.
Source: Abstract No 2501 – poster. Knight MG, Goedeke
JH, Marshall K,
et al
. TG/HDL-C ratio fails to identify
insulin resistance in overweight women of African
descent worldwide.
Glucose uptake by myocytes
more sensitive to fatty acids than
adipocytes
In a laboratory-based study from
Stellenbosch University and the Faculty of
Health Science, Natal, myocytes and adi-
pocytes were exposed to fatty acids, and
insulin-stimulated glucose metabolism was
observed in these cell lines.
The study showed that myocytes
were especially sensitive to fatty acid
exposure, particularly at higher glucose
concentrations, and both glucose uptake
