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““Diabetic foot”Diabetic foot”
INFECTIONINFECTION
NEUROPATHYNEUROPATHY
TRAUMATRAUMA
PADPAD
ULCERULCER
SensoryAutonomicMotor
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Neuropathic: 45-60%
Purely ischaemic: 10%
Mixed neuroischaemic: 25-40%
Diabetic foot ulceration
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Diabetes and PADDiabetes and PAD Spectrum of diseaseSpectrum of disease
Intermittent claudicationIntermittent claudication Rest painRest pain Ulceration/gangreneUlceration/gangrene
Incidental/ScreeningIncidental/Screening
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Intermittent claudicationIntermittent claudication
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Intermittent ClaudicationIntermittent Claudication
Prevalence: 5.3% in patients aged Prevalence: 5.3% in patients aged 45-74yrs45-74yrs
Quality of life: Significantly impairedQuality of life: Significantly impaired Limb Outlook: Relatively benignLimb Outlook: Relatively benign
10% require intervention to prevent 10% require intervention to prevent limb losslimb loss
1% per year require amputation1% per year require amputation Life expectancy: 2-4 X ↑ mortalityLife expectancy: 2-4 X ↑ mortality
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Peripheral Arterial Peripheral Arterial Disease and All-Cause Disease and All-Cause
MortalityMortalityNormal subjects
Asymptomatic PAD†
Symptomatic PAD†
Severe symptomatic PAD†
1.00
0.75
0.50
0.25
0.00
0 2 4 6 8 10 12
Su
rviv
al
Year
•*Kaplan-Meier survival curves based on *Kaplan-Meier survival curves based on mortality from all causesmortality from all causes• ††Large-vessel PADLarge-vessel PAD •1. Criqui MH. Vasc Med 2001; 6(suppl 1): 1. Criqui MH. Vasc Med 2001; 6(suppl 1):
3–7.3–7.
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Odds ratio for risk factors forOdds ratio for risk factors forintermittent claudicationintermittent claudication
Male gender (cf female)
Age (per 10 years)
Diabetes
Smoking
Hypertension
Hypercholesterolemia
Fibrinogen
Alcohol
-2 -1 0 1 2 3 4Protective Harmful
Odds Ratio
Dormandy JA et al. J Vasc Surgery. 2000;31(1 Part 2):S1-S296.
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Intermittent ClaudicationIntermittent Claudicationand diabetesand diabetes
Prevalence: 2 x ↑Prevalence: 2 x ↑ Diabetics – 20% of PAD Diabetics – 20% of PAD
population population Limb Outlook: WorseLimb Outlook: Worse
2x ↑ rest pain, 6x ↑gangrene2x ↑ rest pain, 6x ↑gangrene 80% of amputations occur in 80% of amputations occur in
diabeticsdiabetics Life expectancy: 8 x ↑ mortalityLife expectancy: 8 x ↑ mortality
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Diagnosis: HistoryDiagnosis: History
Intermittent claudication Intermittent claudication
cramp like pain in muscles cramp like pain in muscles
Location: buttock, thigh, calf ,footLocation: buttock, thigh, calf ,foot
occurs on exercising occurs on exercising
relieved by restrelieved by rest
Atypical symptoms Atypical symptoms
are commonare common
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Diagnosis – clinical Diagnosis – clinical examinationexamination
Examination of pulsesExamination of pulses
Peripheral pulses- HIGHLY Peripheral pulses- HIGHLY SUBJECTIVESUBJECTIVE
Rotterdam study Rotterdam study
60% inaccurate60% inaccurate
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Pulses & PADPulses & PAD
Collins 206, 403 pts screenedCollins 206, 403 pts screened PAD prevalence :16.6%PAD prevalence :16.6% Sensitivity of a non detectable pedal pulse -Sensitivity of a non detectable pedal pulse -
18%18% Specificity: 98%Specificity: 98%
Post tibial pulse: sensitivity 33%, Post tibial pulse: sensitivity 33%, specificity 66% specificity 66% ( Brealey S et al)( Brealey S et al)
Probability of agreement of an absent Probability of agreement of an absent pedal pulse between experienced pedal pulse between experienced examiners : 0.49-0.59 examiners : 0.49-0.59 (Marinelli et al)(Marinelli et al)
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Ankle Brachial Pressure Index Ankle Brachial Pressure Index (ABPI)(ABPI)
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Ankle Brachial Pressure Index Ankle Brachial Pressure Index (ABPI)(ABPI)
Ankle pressure (mm Hg)
Brachial pressure (mm Hg)
ABPI =
Value <0.9 indicates PAD
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ABPI – DIAGNOSIS & PROGNOSIS
McKenna et al, atherosclerosis, 1991
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ABPIABPI
Reliable Reliable Positive predictive value -95%Positive predictive value -95% Negative predictive value-99%Negative predictive value-99% But a normal ABPI at rest and classical But a normal ABPI at rest and classical
symptoms may indicate need for symptoms may indicate need for exercise ABPIexercise ABPI
ESSENTIAL FOR DIAGNOSIS ESSENTIAL FOR DIAGNOSIS Do we have expertise in the Do we have expertise in the
community? community?
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Diabetes and ABPIDiabetes and ABPI
Medial calcification: non Medial calcification: non compressible (nc) arteriescompressible (nc) arteries
ABPI in diabetics : 5-10% too ABPI in diabetics : 5-10% too highhigh
Alternatives: Elevate footAlternatives: Elevate foot
Toe pressuresToe pressures
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Toe pressuresToe pressures
Cuff placed around proximal phalanxCuff placed around proximal phalanx Normal pressures are less than Normal pressures are less than
ankle pressuresankle pressures average 24average 24±± 7 – 41 7 – 41±± 17mmHg 17mmHg
Normal ratios compared to brachial Normal ratios compared to brachial 0.72-0.910.72-0.91
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First line : Prolong First line : Prolong lifelife
Risk factor Risk factor managementmanagement
Improve symptomsImprove symptoms
ExerciseExercise
Medical therapyMedical therapy
RevascularisationRevascularisation
CLAUDICATION: CLAUDICATION: SURGICAL TREATMENTSURGICAL TREATMENT
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Treatment Treatment
*Statin for all*Statin for all *Screen for diabetes/ Glycaemic *Screen for diabetes/ Glycaemic
controlcontrol *BP control *BP control Smoking cessation: NRT Smoking cessation: NRT Anti-platelet therapy Anti-platelet therapy Increase exerciseIncrease exercise ACE inhibitor (HOPE study)ACE inhibitor (HOPE study) ReviewReview: ? For revascularisation: ? For revascularisation
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VASCULAR EVENT by PRIOR DISEASEMRC/BHF Heart Protection Study
Risk ratio and 95% CISTATIN PLACEBOBaselinefeature (10269) (10267) STATIN better STATIN worse
STATIN worse
Previous MI 1007 1255
Other CHD (not MI) 452 597
No prior CHD
CVD 182 215
PVD 332 427
Diabetes 279 369
ALL PATIENTS 2042 2606(19.9%) (25.4%)
24%SE 2.6reduction(2P<0.00001)
0.4 0.6 0.8 1.0 1.2 1.4
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Diabetes and PADDiabetes and PAD No clinical trials have been set up No clinical trials have been set up
specifically to investigate glycaemic control. specifically to investigate glycaemic control. Type 2 diabetes,Type 2 diabetes, glycaemia (HbA1C) glycaemia (HbA1C) risk risk
of cardiovascular morbidity and mortality of cardiovascular morbidity and mortality (1) (1)
Each 1% difference in HbA1C Each 1% difference in HbA1C 21% (95% 21% (95% CI 15-27%) change in the risk of diabetes-CI 15-27%) change in the risk of diabetes-related death and a 14% reduction in fatal related death and a 14% reduction in fatal and nonfatal myocardial infarction over 10 and nonfatal myocardial infarction over 10 years (2)years (2)
Turner RC, et al.. BMJ 1998; 316: 823-8.Turner RC, et al.. BMJ 1998; 316: 823-8.Stratton IM et al,. BMJ. 2000;321(7258):405-12.Stratton IM et al,. BMJ. 2000;321(7258):405-12.
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HOPE studyHOPE study Effects of ramipril on patients with Effects of ramipril on patients with 1. symptomatic PAD 1. symptomatic PAD 2. Asymptomatic PAD (ABPI2. Asymptomatic PAD (ABPI ≤ 0.9) plus an ≤ 0.9) plus an
additional coronary risk factor were analysed. additional coronary risk factor were analysed. Only 50% of the patients were defined as Only 50% of the patients were defined as
hypertensive.hypertensive. In both groups- In both groups- ~ 25% reduction in the ~ 25% reduction in the
primary combined outcome of cardiovascular primary combined outcome of cardiovascular mortality, myocardial infarction or stroke with mortality, myocardial infarction or stroke with ramipril. ramipril.
(ABPI) was measured unconventionally(ABPI) was measured unconventionallyOstergren J, et al. Eur Heart J 2004; 25: 17-24.Ostergren J, et al. Eur Heart J 2004; 25: 17-24.
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Diabetes and PADDiabetes and PAD Spectrum of diseaseSpectrum of disease
Intermittent claudicationIntermittent claudication
Rest painRest pain Ulceration/gangreneUlceration/gangrene
Incidental/ScreeningIncidental/Screening
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Severe limb ischaemiaRest pain>2/52, Tissue lossABPI <0.5
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Severe limb ischaemiaRest pain>2/52, Tissue lossABPI <0.5
Critical limb ischaemiaAbsolute ankle pressure<50mmHg
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Neuropathic: 45-60% Purely ischaemic: 10% Mixed neuroischaemic:
25-40%
Diabetic foot ulceration
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Diabetes & foot ulcersDiabetes & foot ulcers
15% develop a foot ulcer15% develop a foot ulcer 12-24% require amputation12-24% require amputation Leading cause of lower limb Leading cause of lower limb
amputationamputation
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Will the ulcer heal?Will the ulcer heal?
Study of patients with foot ulcers and toe Study of patients with foot ulcers and toe amputations amputations
Non-heeling occurred inNon-heeling occurred in(Ramsey et al)(Ramsey et al)
92% of limbs with ankle pressure <80mmHg92% of limbs with ankle pressure <80mmHg But also in 45% of limbs with higher ankle But also in 45% of limbs with higher ankle
pressurespressures
95% of limbs with toe pressures <30mmHg95% of limbs with toe pressures <30mmHg But only in 14% of limbs with higher toe pressures But only in 14% of limbs with higher toe pressures
Toe pressures – greater prognostic valueToe pressures – greater prognostic value PPV 67%, NPV 77% PPV 67%, NPV 77% (Kaloni et al, 1999;Diabetes Care)(Kaloni et al, 1999;Diabetes Care)
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Investigation of PAD in Investigation of PAD in patients with diabetespatients with diabetes
Duplex scanDuplex scan AngiographyAngiography CT CT
angiographyangiography MRA/MRIMRA/MRI
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Figure 1.2Figure 1.2
A
B
C
D
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Diabetes: distribution of Diabetes: distribution of PADPAD
Atherosclerosis in :Atherosclerosis in : Classical sites: Classical sites:
aorto-iliac, Fem aorto-iliac, Fem arteryartery
Medium-sized Medium-sized vessels-vessels- peroneal/tibial peroneal/tibial vesselsvessels
Foot vessels Foot vessels sparedspared
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RevascularisationRevascularisation
AngioplastyAngioplasty By-passBy-pass
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Figure 3.8Figure 3.8
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AmputationAmputation
Minor- infection, osteomyelitisMinor- infection, osteomyelitis
Possible if good blood supplyPossible if good blood supply
Major – extensive soft tissue Major – extensive soft tissue infection or infection or
Insufficient blood supplyInsufficient blood supply 80% of amputees have diabetes80% of amputees have diabetes
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When to refer ?When to refer ? Symptoms:Symptoms: Intermittent claudicationIntermittent claudication Rest pain ( nb neuropathy)Rest pain ( nb neuropathy)
Signs: Signs: low/nc ABPIslow/nc ABPIs Ulceration Ulceration GangreneGangrene
? ? Screening – value for risk factor Mx? ? Screening – value for risk factor Mx
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Asymptomatic PADAsymptomatic PAD
Relatively commonRelatively common Associated with increased mortalityAssociated with increased mortality Can early treatment prevent events ?Can early treatment prevent events ?
2 Major trials will report ‘06/’072 Major trials will report ‘06/’07 Potential to save lives using ABPI:Potential to save lives using ABPI:
a simple a simple non-invasive screening testnon-invasive screening test
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Aspirin for Asymptomatic
Atherosclerosis (AAA) Trial
ABPI<0.95
N=3334
Study Population:Study Population:
men and women men and women
>50 years of age>50 years of age
Study Population:Study Population:
men and women men and women
>50 years of age>50 years of age
££British British Heart Heart
FoundationFoundation
££British British Heart Heart
FoundationFoundation
3- 4 Year3- 4 YearFollow-upFollow-up3- 4 Year3- 4 Year
Follow-upFollow-up
Aspirin Aspirin vs vs
placeboplacebo
EndpointsEndpointsCardiovascularCardiovascular
• Events• Events• Deaths• Deaths
EndpointsEndpointsCardiovascularCardiovascular
• Events• Events• Deaths• Deaths
Fowkes & Douglas, personal communication 2002
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POPADAD
ABPI <0.99Diabetes
Men & women
aged>40 yearsN=8000
Low ABPI in Low ABPI in 20.1%20.1%
Low ABPI in Low ABPI in 20.1%20.1%
Royal CollegeRoyal Collegeof Physiciansof Physicians
Diabetic Diabetic Registry Registry GroupGroup
Royal CollegeRoyal Collegeof Physiciansof Physicians
Diabetic Diabetic Registry Registry GroupGroup
NO clinical evidence of
vascular disease
NO clinical evidence of
vascular disease
££
Medical Medical Research Research Council Council
££
Medical Medical Research Research Council Council
EndpointsEndpointsCardiovascularCardiovascular
• Events• Events• Deaths• Deaths
EndpointsEndpointsCardiovascularCardiovascular
• Events• Events• Deaths• Deaths
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