A prospective study of risk factors for foot ulceration: The West of Ireland Diabetes Foot Study

Background: This is the first study to examine risk factors for diabetic foot ulceration in Irish general practice. Aim: To determine the prevalence of established risk factors for foot ulceration in a community-based cohort, and to explore the potential for estimated glomerular filtration rate (eGFR) to act as a novel risk factor. Design: A prospective observational study. Methods: Patients with diabetes attending 12 (of 17) invited general practices were invited for foot screening. Validated clinical tests were carried out at baseline to assess for vascular and sensory impairment and foot deformity. Ulcer incidence was ascertained by patient self-report and medical record. Patients were re-assessed 18 months later. Results: Of 828 invitees, 563 (68%) attended screening. On examination 23–25% had sensory dysfunction and 18–39% had evidence of vascular impairment. Using the Scottish Intercollegiate Guidelines Network risk stratification system we found the proportion at moderate and high risk of future ulceration to be 25% and 11%, respectively. At follow-up 16/383 patients (4.2%) developed a new foot ulcer (annual incidence rate of 2.6%). We observed an increasing probability of abnormal vascular and sensory test results (pedal pulse palpation, doppler waveform assessment, 10 g monofilament, vibration perception and neuropathy disability score) with declining eGFR levels. We were unable to show an independent association between new ulceration and reduced eGFR [Odds ratio 1.01; P = 0.64]. Conclusions: Our data show the extent of foot complications in a representative sample of diabetes patients in Ireland. Use of eGFR did not improve identification of patients at risk of foot ulceration.