Diabetic foot disease (DFD) refers to a range of disorders in patients with diabetes, which may include the skin, the soft tissues and the bony structures of the foot. Patients with diabetes should routinely undergo assessment in primary care to detect the presence of early or progressive foot disease.
Data from the charity Diabetes UK show that diabetic foot complication is the most common cause of lower limb amputation in the UK, with approximately 100 people per week losing a toe, foot or lower limb.1
DFD is estimated to affect 15 to 25 per cent of patients with diabetes at some time in their lives2 and approximately one in 20 patients with diabetes will develop a foot ulcer in any one year.
More than one in 10 foot ulcers result in amputation of the foot. The risk of leg amputation is more than 15 times higher in patients with diabetes and up to 70 per cent of patients die within five years of having an amputation as a result of diabetes.
Assessing the foot
NICE guidance suggests that structured patient education should be made available to all diabetes patients at the time of initial diagnosis and should be offered on an ongoing basis.3
The guidance also states that educational interventions can improve foot care knowledge and behaviour in the short term.
The common elements of patient education are foot hygiene, awareness of fungal infections and avoidance of cutaneous injuries in the context of peripheral neuropathy.
Education should be delivered by multidisciplinary teams, including a diabetes specialist nurse, with knowledge of the principles of patient education, and a dietitian.
NICE recommends regular visual inspection of patients' feet and assessment of foot sensation. Palpation of foot pulses by trained personnel is important for the detection of risk factors for ulceration.
Examination of patients' feet should include:
- Testing of foot sensation using a 10g monofilament or vibration.
- Palpation of foot pulses.
- Inspection for any foot deformity.
- Inspection of footwear.
NICE also recommends that the risk of DFD should be stratified as:
- Low current risk (normal sensation, palpable pulses).
- At increased risk (neuropathy or absent pulses or other risk factor).
- At high risk (neuropathy or absent pulses plus deformity or skin changes or previous ulcer).
- Ulcerated foot.
QOF
The significant morbidity and mortality associated with DFD presents primary care teams with a considerable challenge and this is recognised by QOF payments as part of the GMS contract.
The proposed changes to QOF in 2011/12 also reflect this risk stratification. Two of the previous indicators are to be retired and replaced by:
- The percentage of patients with diabetes with a record of testing of foot sensation using a 10g monofilament or vibration (using biothesiometer or calibrated tuning fork), within the preceding 15 months.
- The percentage of patients with diabetes with a record of a foot examination and risk classification: 1) low risk (normal sensation, palpable pulses); 2) increased risk (neuropathy or absent pulses); 3) high risk (neuropathy or absent pulses plus deformity or skin changes or previous ulcer); or 4) ulcerated foot within the preceding 15 months.
The other QOF indicators may indirectly contribute to the control of DFD in areas such as blood sugar, BP and cholesterol control.
Management
The diabetes control and complications trial4 and UK prospective diabetes study in type-2 diabetes5,6 demonstrated not only the prevention of progression of DFD with improved glycaemic control but an important 'legacy effect' of early and effective glycaemic control on later progression of diabetic neuropathy.
Primary care teams have an important role in assessing the diabetic foot and reinforcing the importance of prevention of ulceration. Simple wound dressing and proper foot care with blood-spectrum orally administered antibiotics may be important first measures for superficial lesions.
If no improvement is evident in two weeks, secondary referral for more advanced wound care should be considered.
An important treatment for moderate and severe forms of DFD is proper and adequate debridement of necrotic tissue. Necrotic tissue must be sharply debrided back to healthy bleeding tissues.
Infected ulcers should be cultured for both aerobic and anaerobic bacteria.
If patients have suspected or documented osteomyelitis they should be treated with antibiotic therapy for at least four to six weeks, compared with seven to 14 days for patients with an isolated soft tissue infection.
Administration of antibiotics should not be discontinued until the wound appears clean and the surrounding cellulitis has disappeared.
- Dr Kenny is a GP in Dromore, County Down
References
1. Diabetes UK. Putting feet first 2009. www.diabetes.org.uk/Documents/Reports/Putting_Feet_First_010709.pdf
2. Dorresteijn JA N, Kriegsman DM W, Assendelft WJJ et al. Patient education for preventing diabetic foot ulceration. Cochrane Database Syst Rev 2010, Issue 5. Art. No: CD001488.
3. NICE. Type 2 diabetes - footcare CG10. NICE, London, 2004. http://guidance.nice.org.uk/CG10/NICEGuidance/pdf/English
4. Nathan DM, Cleary PA, Backlund JY et al. Intensive diabetes treatment and cardiovascular disease in patients with type 1 diabetes. N Engl J Med 2005; 353 (25): 2643-53.
5. UK Prospective Diabetes Study Group. Perspectives in diabetes, U.K. prospective diabetes study 16. Overview of six years' therapy of Type II diabetes: a progressive disease. Diabetes 1995; 44: 1249-58.
6. UK Prospective Diabetes Study Group. Tight blood pressure control and risk of macrovascular and microvascular complications in type 2 diabetes BMJ 1998; 317: 703-13.
