STRATIFICATION OF PATIENTS WITH DIABETES INTO RISK CATEGORIES FOR FOOT ULCERATION

East Afr Med j. 2009; 86(5)233- 239

Eric Mugambi

The Burden of Diabetes Diabetes is rather uncommon and very fatal…’Dr. Albert Cook, 1901, J trop med 190; 4:175-178

• 194,000,000 (5.1% adult population)

globally

• 3,000,000 deaths/year/globally

• 333,000,000 by 2025

• Kenya – 146,000 diabetics by 2025 (3rd

highest prevalence Africa)

Foot ulcers

• 30 Sec – estimated time a leg is lost to diabetes

• 70% - proportion of amputations related to diabetes

• 85% - proportion of diabetes related amputations preceded by ulcer

• Are you the 6th man?

• 4.9% (82/1788) - prevalence KNH

• 5% - prevalence in developed countries

• 11.4% - admissions attributable to foot ulcer KNH vs. USA/UK (20%)

• 17 weeks - mean ulcer duration

• 80% - ulcerating type

• 20% - gangrenous

• 25% - prevalence of microbial infections

• 0.1%- Charcot’s arthropathy

• 39% - hammer toe deformity

• 23% - diabetics with foot ulcer, with 1 preceding foot

exam

Local data

50% foot ulcers, KNH

20% ulcers KNH

Rare at KNH!5%

Diabetic foot – A Personal, Social and Economic Disaster

• Common cause of admission

• Prolonged in-hospital stay

• Life-long dependence on others

• Inability to work

• Misery

Bottom Line

• Primary prevention

• Cheap, available, validated easy to use tools

• Applicable within clinical setting

Justification

• Identification of modifiable risk factors aids

prevention

• Risk stratification helps in resource allocation

• Targeted allocation of resources reduces re-

ulceration by 60% and amputation by 85%

Methods

• Cross-sectional study

• Diabetic Outpatient Clinic, KNH (Sep 2006-Feb 2007)

• Systematic sampling, sample size = 218

• Ethics • More specifically assessed:

– Neuropathy - NDS

– Peripheral arterial disease - ABI

– Deformity

– Knowledge of foot care

– Monofilament – 5.07

242 met inclusion criteria

218 recruited

24 excluded: • 11 – active ulcers • 8 – diagnosis of DM not certain • 5 – declined participation

Risk factor assessment Physical examination

• NDS • ABPI • Monofilament RBS measurement

Risk categorization • No neuropathy • Neuropathy alone • Neuropathy + either PAD

or deformity • Previous

ulceration/amputation

Outline of study recruitment and methods

ABI

>1.30 - Non compressible

0.91-1.30 - Normal

0.41-0.90 - Mild-Moderate PAD

0.00-0.40 - Severe PAD

NDS

Ankle jerk (0-2)

Vibration (0-1)

Pin prick (0-1)

Temp (0-1)

Score

0-2 – No neuropathy

3-5 – Mild

6-8 – Mod

9-10 - Severe

Demographics

Characteristic Value

Male sex (%) 42

Age in years, mean (+SD) 58 (9)

Duration of DM in years, mean (+SD) 16 (4)

RBS, mmol/l, mean (+SD) 12 (4)

BMI kg/m2, mean (+SD) 26 (3)

OHA (%) 64

Insulin (%) 15

Previous ulcer (%) 16

Previous amputation (%) 8

Risk factors

• Prevalence Neuropathy – 42% (mild 21, mod 17 severe 4)

Peripheral arterial disease – 12%

Deformity – 46% (hallux valgus 14%)

• Monofilament Abnormal in 23% (Sensitivity 100% for severe

neuropathy; 72% for moderate neuropathy)

• Foot care education – 39%

• Foot examination – 12%

IWGDF

GROUP

PERCENTAGE

OF STUDY PATIENTS IN

EACH IWGDF group

ODDS RATIO* FOR

AMPUTATION ADAPTED FROM IWGDF

STUDY

0 NO NEUROPATHY

57 NA

1 NEUROPATHY ALONE

10 1.7

2 NEUROPATHY PLUS

EITHER PAD OR

DEFORMITY

16 12.1

3 PREVIOUS

ULCER/AMPUTATION

17 36.4

*Lawrence lavery et al, ARCH INT

MED/VOL 158 JAN 26, 1998

Risk Categories

Recommendation for follow up

• Group 0 – annual review

• Group 1 – semi-annual review

• Group 2 – quarterly review

• Group 3 – every 1 to 3 months

Conclusions

• One third (33%) of diabetic patients were at high risk for future foot ulceration:

– It is cost-effective to set up a separate foot clinic

– The opportunity cost is too high

• The 5.07 monofilament is a reliable easy to use tool in the detection of severe neuropathy, and can be easily adapted into our local setting

Thank you

Remember: In the time it has taken to deliver this

lecture, some 30 legs have been lost to diabetes!

Examine the feet of your diabetic patients!