Contribution of 30-day readmissions to the increasing costs of care for the diabetic foot

Objective: The inpatient cost of care for diabetic foot ulcers (DFUs) has been estimated to be $1.4 billion annually in the United States. We have previously demonstrated that the risk of 30-day unplanned readmission for patients with DFU is nearly 22%. Our aim was to quantify the cost of readmissions for patients admitted with DFU. Methods: All patients presenting to our multidisciplinary diabetic limb preservation service from June 2012 to June 2016 were enrolled in a prospective database. Inpatient costs and net margins were calculated overall and for index admissions vs 30-day unplanned readmissions. Results: A total of 249 admissions for 150 patients were included. Of these, 206 admissions were index admissions and 43 were 30-day readmissions. The most common reason for readmission was the foot wound (49%), followed by a bypass wound (14%), renal complications (9%), and other systemic complications. Surgical interventions during readmission were common (47%) and included both podiatric (37%) and vascular (23%). The wound healing outcomes were favorable, with 78% of all wounds achieving healing by 1 year. Limb salvage was 91% overall. The median hospital cost per admission was $20,111 (interquartile range, $12,589-$33,254) and did not differ between the index and readmissions ($22,165 vs $19,408; P = .46). However, the hospital net margins were lower after readmission ($3908 vs $1975; P = .02). The overall cost of care for patients requiring readmission was significantly greater than that for patients not readmitted ($79,315 vs $28,977; P < .001). During the study period, DFU care at our institution cost $7.9 million, of which $1.2 million (16%) was attributable to readmission costs. Conclusions: Readmissions for patients with DFU are common and associated with a substantial cost burden. The cost of readmission for patients with DFU was as high as the cost of the index admission but with lower hospital net margins. When extrapolated to national data, the 15% readmission cost burden we have reported would be equivalent to $210 million hospital costs annually. Focused efforts at preventing readmissions in this high-risk patient population are essential to reducing the overall costs of care associated with DFUs.