Page 46 - The SA Journal Diabetes & Vascular Disease Volume 9 No 4 (November 2012)

188 VOLUME 9 NUMBER 4 • NOVEMBER 2012
REPORT SA JOURNAL OF DIABETES & VASCULAR DISEASE
ous metabolic derangements and it has even
been suggested that their mortality rates
could be higher than those of overweight
patients. ‘Annual screening is therefore valu-
able and cost-effective in the elderly, even
those who are asymptomatic, as the presen-
tation is often vague and one can’t rely on
the classic symptoms’, said Dr Landau.
Healthcare professionals need to bear
in mind that more often than not, elderly
patients with diabetes will have a number of
other interconnected syndromes, part of the
so-called geriatric syndrome complex, which
affect delivery of care. They include poly-
pharmacy (e.g. with NSAIDs and tricyclic
antidepressants), depression, impaired cog-
nitive functioning, urinary incontinence, falls
and fractures, malnutrition and pain.
Dr Landau pointed out that treatment
needs to be tailored to each individual patient.
‘Age is not a contra-indication to metformin,
glomerular filtration rate is. Modified-release
glicazide is the safest sulphonylurea and
insulin initiation should not be delayed if
indicated. With regard to incretin therapies,
DPP4s, which are safe, are advisable in elderly
patients, although they are likely to have more
side effects. GLP-1 agonists can be safely used,
even though their non-glycaemic benefits are
muted in this population.’
Patient-centred care has never mattered
more. ‘We need to be respectful of and
responsive to individual patient needs and to
involve the families. It’s important to under-
take a functional assessment, a vascular risk
assessment, ascertain appropriate metabolic
targets and devise appropriate interventions
for diabetes-related disabilities, as well as
assess whether a caregiver is required.’
There is currently a paucity of guidelines for
older patients with diabetes, but an interna-
tional collaboration has recently established
a treatment hierarchy for this population,
identifying the recognition and avoidance of
hypoglycaemia as the most valuable interven-
tion. The blunting of the glucagon response
in elderly patients makes hypoglycaemia even
more problematic than in the younger patient,
as a hypoglycaemic episode could precipitate
a fall and hip fracture that may potentially be
the terminal event.
‘ There are three kinds of patients: the inde-
pendent and mobile, the exceptionally frail,
and those in the middle. The more well the
patient is, the more intensive the treatment’,
said Dr Landau, underscoring that function-
ality, rather than age itself, needs to be the
key criterion. ‘While we need to deliver opti-
mal care to the functional, in the frail we
must focus on avoiding hypoglycaemia and
addressing the acute symptoms.’
Vitamin D and diabetes: a D-lemma
Dr Marli Conradie, Division of Endocrinol-
ogy and Metabolism, Department of
Medicine, University of Stellenbosch
Vitamin D deficiency has been implicated
among novel risk factors for the develop-
ment of type 2 diabetes. In the diabetic
patient, improved vitamin D levels have been
associated with improvements in beta-cell
function, insulin action and systemic inflam-
mation. Vitamin D is also known to have an
immunomodulatory function.
Vitamin D3 is produced in the skin under
the influence of ultraviolet light and vitamin
D2 is derived from the diet in foods such as
fatty fish and egg yolk. Both forms of vita-
min D can be stored in the adipose tissue,
and hydroxylation in the liver produces cal-
cidiol [25(OH) vitamin D]. Calcidiol is further
converted in the kidney to the biologically
active calcitriol [1.25(OH)2 vitamin D].
Vitamin D receptors are ubiquitous in all
tissues of the body. Furthermore, many tis-
sues (including the pancreas) possess the
enzymes to produce calcitriol locally. This
may explain why vitamin D appears to play
an essential role in overall health.
In terms of type 1 diabetes, lower levels
of vitamin D are associated with increased
all-cause mortality. Dr Conradie referred to
a Swiss study on vitamin D supplementation
in children from birth, with a 30-year follow
up. Results indicated a decreased prevalence
of type 1 diabetes in those receiving vitamin
D supplementation. Similarly, the populations
exposed to the most sunshine (i.e. equatorial)
have the lowest prevalence of type 1 diabetes.
A seasonal variation in glycaemic control
has been noted in type 2 diabetes. Control
is worse in the colder months, although this
could also be ascribed to the winter propen-
sity for inactivity and overeating.
Measurements of calcidiol are used to
determine vitamin D status, providing a
good reflection of dietary intake and sun
exposure. Normal values are considered to
be above 30 ng/ml, a deficiency is below 10
ng/ml, and an insufficiency if levels fall in
between this range.
Most type 2 diabetes patients and those
with impaired glucose tolerance have lower
levels of calcidiol. An inverse relationship
between calcidiol levels and duration of type
2 diabetes has also been noted. Furthermore,
higher body mass index and HbA1c levels are
associated with lower vitamin D levels. High
plasma levels of calcidiol have been impli-
cated in decreased risk of diabetes.
Dr Conradie took care to emphasise that
the outcomes of the observational studies to
which she referred did not prove causality
and that the studies themselves were in vari-
ous ways flawed. Currently, routine meas-
urement and supplementation of vitamin
D cannot be recommended for diabetes-
related outcomes.
A long walk to better foot care
in South Africa
Ms Tracey Johnson, podiatrist, Sydney,
Australia
In South Africa, the diabetic patient faces a
high risk of foot amputation. One in six dia-
betic patients will get a foot ulcer. Of total
leg amputations, 70% are performed on
diabetic patients. The South African public
sector bears 84% of the diabetic burden, of
which 68% of patients have never had their
feet examined by a healthcare practitioner.
Peripheral neuropathy is present in 74%
of black South African diabetics and the two-
year mortality post vascular surgery is 19%.
With these sobering statistics in mind, Ms
Johnson pondered the question of whether
South African healthcare professionals are
sufficiently knowledgeable and equipped
to deal with the foot problems commonly
encountered in diabetes.
A dearth of South African research per-
taining to the foot in diabetes has led to
an informal survey titled ‘The foot in diabe-
tes’. Delegates attending this presentation
participated in the survey, adding to infor-
mation previously gleaned from delegates
attending the 10th CDE postgraduate forum
(2008) and the 2010 Diabetic Foot working
group conference, as well as participants
of the CDE advanced courses in diabetes
care for health professionals (2008–2010).
The survey has revealed that South Afri-
can healthcare professionals are not suit-
ably empowered to assess and manage the
effects of diabetes on the feet.