Costs Attributable to Diabetic Foot Ulcers: A Bottom-up Economic Model

Approximately one in four patients with diabetes will suffer a lower extremity wound, resulting in staggering mortality, disability, and resource utilization. It has been reported that one-third of all diabetes-related costs are attributable to the treatment of foot ulcers. Unfortunately, studies characterizing the economic burden of diabetic foot complications exhibit considerable heterogeneity. Estimates vary depending on study methods, data source, care environment, study perspective, and whether (and how) incident or prevalent populations are considered. Chan and colleagues completed a systematic review in 2017 and identified only two studies reporting net disease-specific costs of foot ulcers: Ramsay 1999 ($54,887 over two years) and Rice 2014 ($19,058 over one year), each inflated to 2019 dollars.

To address the scarcity and limitations of existing top-down economic studies, we present a bottom-up economic model to characterize the costs attributable to diabetic foot ulcers. Our model takes as input assumptions related to mix of ulcer severity at presentation, wound care treatment practice, daily inpatient costs, and healing, amputation, and mortality rates. To demonstrate the model’s utility, we used input from more than 50 references to estimate the cost to treat a foot ulcer in the Veterans Health Administration. We then compared these costs under standard care to those that would hypothetically be incurred were veterans to practice once-daily foot temperature monitoring.

We calculated net costs of $55,381 under standard care, which compares favorably to Ramsay 1999. Consistent with Rice 2014, we estimated that approximately 59% of these costs would be incurred during inpatient stays. We estimated that foot temperature monitoring has the potential to eliminate 81% of attributable costs. Use of bottom-up economic models for the diabetic foot can augment existing cost-of-illness studies and enable decision-makers to explore the cost implications of emerging technologies and clinical practices.