Diabetic foot ulcer: a systematic review of risk factors

BACKGROUND: This study used a systematic analysis to identify risk factors that may be used to predict which patients with diabetes will develop a foot ulcer. METHODS: A systematic review of the literature was conducted, which included observational cohort studies that followed patients with diabetes to see whether they developed a diabetic foot ulcer (DFU). A random-effect meta-analysis was performed, and odds ratios were used for nominal data or mean differences for continuous data. This study was registered at PROSPERO (CRD42020182527). RESULTS: The analysis included eight studies. From 4914 patients, 607 developed a DFU (12%) within a median of 30 months follow-up, indicating a 4.8% annual rate. The following parameters were found to be related to DFU development: a history of DFUs; cerebrovascular accident; peripheral arterial disease and lower extremity amputation; duration of diabetes; glycated haemoglobin; use of insulin; visual impairment; claudication; altered monofilament sensitivity; foot deformity; onychomycosis; foot oedema; and local hyperkeratosis. The quality of evidence for most of the factors was either low or very low. CONCLUSION: The development of DFUs may be associated with various factors, including: a history of previous DFUs; amputation or clinical atherosclerosis syndrome, such as peripheral arterial and cerebrovascular disease; the severity of diabetes; and various clinical signs regarding the patient's foot. The low certainty of evidence for most of these factors indicates that there is still a gap in knowledge regarding the early detection of foot ulcers in people with diabetes. A large prospective study could identify more precisely which factors are the most significant. Contemporary technology could use such data to create devices that would be able to predict DFUs so they can be prevented or treated earlier, which would reduce the possibility of lower limb amputation.