Basic HTML Version
90
VOLUME 9 NUMBER 2 • JUNE 2012
EDUCATOR’S FOCUS
SA JOURNAL OF DIABETES & VASCULAR DISEASE
PAD presents at an earlier age in people with diabetes, and the proc-
ess is more rapid than in the non-diabetic population.
9
This is noted in
the proposed protocol for the evaluation of patients in whom PAD is sus-
pected (Fig. 1). Patients are at increased risk for PAD if their age is above
50 years and they are diabetic or smokers, compared to 70 years old in
those without diabetes.
8
DIAGNOSIS OF PAD
Clinical practice guidelines on preventative management of the diabetic
foot, such as the American Diabetes Association (ADA) position state-
ment on foot care, the Scottish Intercollegiate Guideline Network (SIGN),
the National Institute for Clinical Excellence (NICE), and the International
Working Group on the Diabetic Foot (IWGDF), recommend an annual foot
assessment to identify those at risk for ulceration
11-14
(Table 1). Screening
the feet for PAD should start with taking a history of age, cardiovascular
risks, symptoms of intermittent claudication, skin integrity, colour, pres-
ence of ulcers, hair growth and temperature.
The pedal pulses should be examined: absence of both pedal pulses,
dorsalis pedis and posterior tibial pulse, may be associated with PAD
and should be investigated further (Fig. 2). The ABPI is indicated in all
patients suspected of PAD. The ADA guidelines recommend that an
ABPI be performed in patients with diabetes who are older than 50
years and patients under 50 years who have other risks factors such as
smoking, hypertension, hyperlipidaemia, or duration of diabetes more
than 10 years.
Patients with significant symptoms and signs of PAD should be re-
ferred immediately for further vascular assessment. Risk-factor modifica-
tion should be introduced early to improve outcome.
INTERMITTENT CLAUDICATION
The classical symptom of intermittent claudication is muscle discomfort
in the lower leg, brought on by exercise and relieved within 10 minutes
by rest.
15
The location of the pain is determined by the level of stenosis
and is most commonly in the calf. This may be the only clear primary
symptom in patients with PAD.
Questionnaires have been developed and used to diagnose symptoms
Table 1.
Risk stratification system (SIGN 2010).
Low risk
No risk factors, e.g. loss of protective sensation, no
signs of PAD and no other signs of risk factors
Moderate risk
One risk factor present, e.g. loss of protective sensa-
tion, or signs of PAD without callus formation or
deformity
High risk
Previous ulceration or amputation or more than one
risk factor present, e.g. loss of protective sensation or
signs of PAD with callus or deformity
Fig. 1.
Proposed protocol for the diagnosis of PAD in patients with diabetes mellitus
(Hiatt
15
).
ABPI measurement
Assess
other
causes of
leg symp-
toms
Normal
results:
no PAD
Post-exercise ABPI
measurement
Refer vascular unit:
TPI measurement
Duplex ultra-
sonography
Abnor-
mal
results
PAD
Normal
post-
exercise
ABPI
Decreased
post-
exercise
ABPI
Patient history and physical examination
Age 50 to 69 years and smoking or diabetes
Leg pain with exertion and reduced physical functioning
Abnormal results on vascular examination of leg
Coronary, carotid, renal arterial disease
ABPI > 1.4
ABPI < 0.9
ABPI = 0.91–1.4
Fig. 2.
Location of pedal pulses.