American Cancer Society; Centers for Disease Control and Prevention; Swiss Re; Swiss Cancer Research foundation; Swiss Cancer League; Institut National du Cancer; La Ligue Contre le Cancer; Rossy Family Foundation; US National Cancer Institute; and the Susan G Komen Foundation.

National Key R&D Program of China, PUMC Youth Fund and the Fundamental Research Funds for the Central Universities, and Major State Basic Innovation Program of the Chinese Academy of Medical Sciences.

To determine the annual incidence and clinically relevant risk factors for foot ulceration in a large cohort study of diabetic foot ulcer (DFU) patients and diabetes mellitus (DM) patients in China. To investigate a cohort of 1,333 patients comprising 452 DFU patients and 881 DM patients, who underwent foot screening, physical examination, and laboratory tests in eight hospitals. The patients were assessed at baseline in terms of their demographic information, medical and social history, peripheral neuropathy disease (PND) screening, periphery artery disease (PAD) screening, assessment of nutritional status, and diabetic control. One year later, the patients were followed up to determine the incidence of new foot ulcers, amputation, and mortality. By univariate analysis, statistically significant differences were found in age, location, gender, living alone (yes/no), occupation, smoking, hypertension, PND, PAD, nephropathy, retinopathy, cataracts, duration of diabetes, Glycosylated hemoglobin A (HbA1c), fasting plasma glucose level, postprandial blood glucose level, insulin level, blood urea nitrogen, creatinine, cholesterol, triglyeride, high density lipoprotein (HDL), serum albumin, white blood cell, and body mass index. A binary logistic regression model was used to examine which of these risk factors were independent risk factors for foot ulceration. A total of 687 (51.5%) of the 1,333 patients were followed up for an average of 12 months; there were 458 DM patients and 229 DFU patients. A total of 46 patients died during the follow-up period; 13 were DM patients, and 33 were DFU patients. Of the 641 patients, 445 (69.4%) patients were DM patients, and 196 (30.6%) were DFU patients. At follow-up, 36/445 DM patients (8.1%), and 62/196 DFU patients (31.6%), developed new ulcers; 10/196 DFU patients underwent an amputation. The annual incidence of ulceration for DM patients and amputation for DFU patients were 8.1 and 5.1%, respectively. The annual mortality of the DM patients and DMF patients were 2.8 and 14.4%, respectively. A binary logistic regression model was used to examine which risk factors were independent risk factors for foot ulceration during the follow-up period, and the final results showed that nephropathy (odds ratio 2.32), insulin level (odds ratio 3.136, 2.629), and decreased HDL (odds ratio 0.427) were associated with increased risks for foot ulceration. Complications of diabetes affecting the feet represent a serious problem in China. The incidence of foot ulcers and amputation are much higher than that of Western countries. More intensive surveillance and aggressive care following a diagnosis of DFU and earlier referral to specialty care might improve the patient outcome.

To determine incidence and clinically relevant risk factors for diabetic amputation in a large cohort study of diabetic foot ulceration patients in China, we investigated a total of 669 diabetic foot ulceration patients, who were assessed at baseline for demographic information, medical and social history, peripheral neuropathy screening, periphery artery disease screening, assessment of nutritional status and diabetic control, physical examination including foot deformity in 15 Grade III-A hospitals. Of the 669 patients, 435 were male and 201 were female, with the mean age being 64.0 years. Of all patients, 110 had neuropathic ulcers, 122 had ischemic ulcers, 276 had neuroischemic ulcers, and 12 cases were unclassified. Wagner classification showed 61 cases were grade I, 216 cases grade II, 159 cases grade III, 137 cases grade IV, and 7 cases grade V. The overall amputation rate among diabetic foot patients was 19.03%, and major and minor amputation rates were 2.14% and 16.88%, respectively. By univariate analysis, statistically significant differences were found in smoking, rest pain, ulcer history, revascularization history, amputation history, gangrene, infection, Wagner grades, duration of diabetes, and postprandial blood glucose, aldehyde, total protein, globulin, albumin, white blood cell (WBC), hemoglobin, HbA1c, ulcer property, body mass index, as well as creatinine. Binary logistic regression model showed that increased WBC (odds ratio 1.25) and ulcer history (odds ratio 6.8) were associated with increased risks from diabetic foot ulcer to major amputation; increased duration of diabetes (odds ratio 1.004), WBC (odds ratio 1.102), infection (odds ratio 2.323), foot deformity (odds ratio 1.973), revascularization history (odds ratio 2.662), and decreased postprandial blood sugar (odds ratio 0.94) were associated with increased risks from diabetic foot ulcer to minor amputation. It is of great importance to give better management to diabetic patients at early stages. Following a diagnosis of DFU more intensive surveillance and aggressive care may improve outcome.