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Objective

To estimate the costs from delaying major amputation in patients with concurrent diabetic foot ulcer and peripheral vascular disease. We seek to model economic benefits from saved costs from promoting timely major amputations among these patients.

Methods

Retrospective modeling using data from National University Hospital, Singapore. We identified patients who might have delayed major amputations by applying a hierarchical clustering algorithm. We then modeled the transitions of all patients over time with a Markov process using a number of relevant health states to enable estimation of cost outcomes. We next summarized the expected changes to the bed days used and cost outcomes arising from reassigning some patients who may have had a delayed amputation to timely amputation. The findings from the sample were scaled to reflect national incidence rates for this disease for the years 2014–2019 in Singapore.

Results and Conclusions

Nine of the 137 patients (6.57%) would be suitable for a major amputation at 3 months, yet in reality, their amputation was delayed. Based on this, and assuming a timely amputation is done for the entire population of patients in Singapore we expect annual savings of 264,791 bed days and $211 million in costs. These findings are preliminary and uncertain. The value of this paper is to show a method for estimating outcomes, report the findings from a small sample, and stimulate future research. New cohort studies might be designed to capture a wider range of outcomes and recruit a larger sample of individuals.


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Decision‐making for early major amputation in selected diabetic foot ulcer patients with peripheral vascular disease

Show Author's information Lim York Tee Gorden1Ying Fangting Ariel2Ho Pei3Lingyan Meng3N. G. Yi Zhen1Nicholas Graves2 ( )
Wound Care Innovation for the Tropics Programme, Skin Research Institute of Singapore, A*STAR, Singapore, Singapore
Health Services and Systems Research, Duke‐NUS Medical School, Singapore, Singapore
Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore

Abstract

Objective

To estimate the costs from delaying major amputation in patients with concurrent diabetic foot ulcer and peripheral vascular disease. We seek to model economic benefits from saved costs from promoting timely major amputations among these patients.

Methods

Retrospective modeling using data from National University Hospital, Singapore. We identified patients who might have delayed major amputations by applying a hierarchical clustering algorithm. We then modeled the transitions of all patients over time with a Markov process using a number of relevant health states to enable estimation of cost outcomes. We next summarized the expected changes to the bed days used and cost outcomes arising from reassigning some patients who may have had a delayed amputation to timely amputation. The findings from the sample were scaled to reflect national incidence rates for this disease for the years 2014–2019 in Singapore.

Results and Conclusions

Nine of the 137 patients (6.57%) would be suitable for a major amputation at 3 months, yet in reality, their amputation was delayed. Based on this, and assuming a timely amputation is done for the entire population of patients in Singapore we expect annual savings of 264,791 bed days and $211 million in costs. These findings are preliminary and uncertain. The value of this paper is to show a method for estimating outcomes, report the findings from a small sample, and stimulate future research. New cohort studies might be designed to capture a wider range of outcomes and recruit a larger sample of individuals.

Keywords: amputations, patients, costs

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Publication history
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Publication history

Received: 15 June 2022
Accepted: 17 August 2022
Published: 19 September 2022
Issue date: October 2022

Copyright

© 2022 The Authors.

Acknowledgements

We acknowledge the support of the Wound Care in the Tropics Programme, under the Skin Research Institute of Singapore. This study is supported by the Agency for Science, Technology and Research (A*STAR) under its Industry Alignment Fund‐Pre‐Positioning Programme (IAF‐PP) grant number H1X/01/a0/OX9 as part of the Wound Care Innovation for the Tropics (WCIT) Programme.

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This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

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