Congestive heart failure presence predicts delayed healing of foot ulcers in diabetes : an audit from a multidisciplinary high-risk foot clinic

Aims: This retrospective study aimed to investigate both established and less well-explored factors as potential predictive variables for failed and delayed ulcer healing. Methods: Patients with type 1 or 2 diabetes with foot ulceration presenting consecutively to, and then subsequently managed at, a multidisciplinary, high-risk foot clinic were followed until ulcer healing, amputation or death. Data comprised prospective standardised documentation at each visit and retrospective collection from hospital records, and included patient demographics, comorbidities, laboratory variables, and ulcer infection, depth and area at each presentation. Multiple regression analysis was used to determine independent predictors of failure to heal and delayed healing. Results: Of the 107 consecutive patients studied, 95 (89%) healed overall, 50 (47%) had healed in 12 weeks and the mean healing rate was a 10% decrease in ulcer area per week. Amongst all variables examined, comorbid congestive heart failure (CHF) was the only factor independently predictive of all measured outcomes of failure to heal overall, delayed healing at 12 weeks, and reduced healing rate. Ulcer infection at presentation, longer duration of antibiotic use, and liver enzyme abnormalities of raised ALT and AST:ALT < 1 (each suggestive of non-alcoholic fatty liver disease), were also predictive of poor ulcer outcomes. Conclusions: Comorbid congestive cardiac failure is predictive of delayed foot ulcer healing rate as well as a lower probability of healing overall. Liver enzyme abnormalities also predicted delayed ulcer healing outcomes. The mechanisms underlying these associations with foot ulcer outcomes in diabetes are unclear. Further studies are needed to determine the role of systematic routine documentation of heart failure and its severity, and then targeting of heart failure to potentially aid the management of foot ulcers in diabetes.