An assessment of peripheral vascular disease in patients with diabetic foot ulcer.

BACKGROUND: Peripheral vascular disease (PVD) is a chronic limb ischaemia caused by atherosclerosis of the peripheral arteries. Diabetes mellitus is a risk factor for this disease. The most common symptom of PVD is muscle pain in the lower limbs on exercise. In diabetes, pain perception may be blunted by the presence of peripheral neuropathy. Therefore, a patient with diabetes and PVD is more likely to present with an ischaemic ulcer or gangrene than a patient without diabetes. The use of ankle-brachial-pressure index (ABI) in the clinic and bedside provide a measure of blood flow to the ankle. This could help early detection, initiate early therapy and may thus reduce the risk of critical limb ischaemia and limb loss.

OBJECTIVE: The purpose of this study is to evaluate the occurrence of peripheral vascular disease using ankle-brachial index in diabetic patients with and without foot ulcers and the risk factors associated with diabetic foot ulcer (DFU).

METHOD: This prospective study involved all type 2 DM patients with foot ulcer (DFU population) and those without foot ulcers (non-DFU population) seen in our hospital. Their demographic, clinical and laboratory parameters were noted and documented. Measurement of ABI was done using a portable hand held Doppler and ankle pressures<0.9 is suggestive of PVD.

RESULTS: A total of 74 patients were recruited. Males were 42 (56.8%) and females were 32 (43.2%). The mean age of the patients was 62.89±10.66 years and the duration of diabetes was 7.61±7.57 years. Forty-six (62.2%) presented with foot ulcer while 28 (37.8%) were without foot ulcer. Patients with PVD represented by ABI<0.9 was DFU 31(76.4%) while in non-DFU it was 10 (13.4%). Multivariant analysis of variables associated with DFU in those with ABI<0.9 showed correlation with tobacco use r=.235, p=0.044; duration of diabetes r=-.427; p=0.001; and systolic blood pressure r=-.301; p=0.009.

DISCUSSION: The occurrence of PVD determined by the absence of >2 pulses by palpation alone and using ABI was 25.7% and 55.4% respectively. This suggests that assessment by palpation is subjective while the use of Doppler is quantitative and more reliable. DFU patients with PVD showed a significant correlation with tobacco use, duration of diabetes and systolic blood pressure but not with dyslipidaemia.

CONCLUSION: This study shows that these patients had risk factors for PVD. The use of hand held Doppler will aid early diagnosis of critical limb at risk of loss and help to prevent and reduce the high rate of limb loss in our patients.