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ABC of Diabetes
by Peter J. Watkins
Treatment of Type 2 diabetes mellitus
Type 2 diabetes is a complex disorder generally affecting
older people who are often overweight and likely to suffer
other medical problems as well. Its management presents
considerable challenges to medical and nursing staff, whose
care must be directed at the sum of the problems of the
individual patient. Management now requires not only
attention to blood glucose control, but also to the
treatment of hypertension and hyperlipidaemia, as well as
introducing the necessary measures for reducing
cardiovascular risk factors.
Optimal treatment of Type 2
diabetic patients, especially those who are symptom-free,
overweight and have in addition several cardiovascular risk
factors, exercises our clinical skills and judgments to the
limit. There needs to be a sense of reality within the
consultation, bearing in mind the potential dangers of
unacceptable polypharmacy accompanied by low adherence to
prescribed treatment as well as a sense of guilt experienced
by those who fail to achieve ideal targets set by
physicians. Awareness of the priorities and intentions of
individual patients needs to be given consideration, and
patients need to agree on the objectives for treatment.
Recommendations for treatment must be clinically relevant
for the individual patient, who should be involved in
choosing which of the many therapeutic options to select
after explanation of advantages and risks. The difficulties
of controlling Type 2 diabetes tend to increase with the
passage of time as the disease progresses. Management is
often difficult and needs to be pragmatic: the late
Professor John Malins when asked how this should be done
used to quote the advice given by Chekhov to his actors—that
it should be “done as well as possible”.
Glycaemic control
Natural history
Type 2 diabetes is an insidiously progressive disease.
Gradually decreasing insulin secretion leads to a slow
increase in hyperglycaemia and a rise of HbA1c values, often
despite vigorous clinical attempts to maintain control.
Thus, while control during the early years is often
straightforward, it becomes increasingly difficult with the
passage of time, so that the appropriate need for tablets
and insulin requires continuing consideration.
Non-obese patients
Such patients require different consideration from the
obese. They are much more likely to require insulin early in
the course of treatment, and indeed apparent presentation as
Type 2 diabetes may be deceptive when they progress to Type
1 diabetes as cases of latent autoimmune diabetes of
adulthood (LADA). Sulphonylurea treatment is used initially
while metformin treatment is inappropriate for these
patients. Some of them cling desperately to minute diets
with the large doses of sulphonylureas as weight and health
decline: these patients regain their health rapidly when
insulin treatment is started and indeed it should not be
delayed.
Obese patients
These patients require a different approach. The need for
healthy eating and exercise in an attempt to reduce weight
are paramount yet difficult to achieve. When these measures
fail, metformin is the first choice, and will to a small
extent diminish the weight gain which comes almost
inevitably with improved glycaemic control. A sulphonylurea
or meglitidine analogue is added when metformin alone fails.
The use of thiazolidinediones is described below.
Patients who remain unwell and often symptomatic (thirst and
nocturia especially) and who continue to lose weight should
be switched to insulin without delay.
Achieving glycaemic
control and reducing risk factors
* Healthy lifestyle advice—healthy eating plan, exercise,
and weight reduction plan.
* Oral hypoglycaemic agents should be given only when
dietary treatment alone has failed after a proper trial
period, usually lasting at least three months. They should
not normally be given as the initial treatment (this is a
common error).
* Sulphonylureas stimulate insulin secretion
* Meglitidine analogues stimulate insulin secretion
* Biguanides (metformin) reduce hepatic gluconeogenesis and
enhance glucose uptake
* Thiazolidinediones enhance insulin sensitivity
* glucosidase inhibitors (acarbose) reduce absorption of
complex carbohydrates.
* Pharmacological agents to assist weight reduction:
* Orlistat inhibits pancreatic lipase and reduces fat
absorption
* Sibutramine is a monoamine reuptake inhibitor, causing
reduced appetite
* Antihypertensive and lipid lowering agents (see chapter
17).
Note: The rest of the chapter
is omitted.
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