Cost-effectiveness of Diagnostic Tools to Establish the Presence of Peripheral Arterial Disease in People With Diabetes

Abstract

Objective: To evaluate the cost-effectiveness of point-of-care duplex ultrasound (PAD-scan) and other bedside tests for the diagnosis of peripheral arterial disease (PAD) in people with diabetes. Background: PAD is a risk factor for cardiovascular disease, diabetic foot ulceration (DFU), and amputation in diabetic patients. Diagnosis enables optimization of therapies to manage these risks. PAD-scan can be performed by frontline staff and has been shown to be the most accurate bedside test. However, its cost-effectiveness has not been investigated. Methods: A Markov model was constructed to estimate the health outcomes and costs over 5 years of different testing strategies applied to a cohort of diabetic patients. Bedside tests investigated were PAD-scan, ankle-brachial pressure index, toe-brachial pressure index, audible and visual Doppler, transcutaneous pressure of oxygen, and pulse palpation. Health outcomes were incidence of new DFU, major cardiovascular events, amputation, death, and DFU healing rates. Sensitivity analyses were performed. Results: PAD-scan was the most cost-effective bedside test with an incremental cost-effectiveness ratio of £11,391/quality-adjusted life years. PADscan had the highest probability (78.7%) of having the greatest net benefit at a willingness to pay threshold of £20,000 per quality-adjusted life years. It reduced the number of amputations by 24% and the number of cardiovascular deaths by 10% over 5 years, compared to toe-brachial pressure index (next best alternative). PAD-scans superiority in incremental cost-effectiveness ratio occurred at a PAD prevalence threshold of 0.24. Discussion: PAD-scan is a cost-effective test for the detection of PAD in patients with diabetes.

Evaluating the prognostic performance of bedside tests used for peripheral arterial disease diagnosis in the prediction of diabetic foot ulcer healing

“…The recent Testing for Arterial Disease in Diabetes (TrEAD) study compared the diagnostic performance of bedside tests for the diagnosis of PAD in diabetes. 11 The results demonstrated that the visual waveform assessment is the most accurate 11 and cost-effective 12 diagnostic modality as compared with commonly used tests. However, the prognostic value of these tests in predicting wound healing remains unclear and has not been subject to a side-by-side comparison in the same group of patients.…”

Study protocol for a multicentre comparative diagnostic accuracy study of tools to establish the presence and severity of peripheral arterial disease in people with diabetes mellitus: the DM PAD study

“…A literature review will be conducted to identify published health economic studies in similar patient groups. The structure and evidence that will be used in constructing the model will be determined following this review but may follow and update previous work by this group 14. Depending on ulceration status at presentation, this model classified patients into one of eight initial states following a test: true positive (with and without DFU), true negative (with and without DFU), false positive (with and without DFU) or false negative (with and without DFU).…”

“…The structure and evidence that will be used in constructing the model will be determined following this review but may follow and update previous Open access work by group. 14 Depending on ulceration status at presentation, this model classified patients into one of eight initial states following a test: true positive (with and without DFU), true negative (with and without DFU), false positive (with and without DFU) or false negative (with and without DFU). It was assumed that true and false positive patients without DFU would be prescribed orthotics and additional foot checks, in addition to standard care.…”

“…The results of this study suggest that visual waveform assessment may be a promising modality. Furthermore, health economics modelling of the TrEAD data suggests that visual waveform assessment is the most cost-effective test (incremental cost-effectiveness ratio (ICER) £11 391), and that its use would result in a reduction in the number of amputations by 24% and cardiovascular deaths by 10% over 5 years as compared with next best alternative 14. However, these findings need to be further validated in a multicentre diagnostic accuracy study which addresses limitations relating to currently available evidence.…”

“…Missed diagnosis of PAD is common,22 and is an important cause of avoidable amputations 22–24. Health economic modelling has demonstrated that improvements in the detection of PAD are not only cost-effective, but also may considerably reduce the number of lower limb amputations and cardiovascular deaths by enabling clinicians to optimise treatment 14. This will help mitigate the expected rise in disease (both PAD and diabetes) prevalence.…”