An integrated personalized assistive devices approach to reduce the risk of foot ulcer recurrence in diabetes (DIASSIST): study protocol for a multicenter randomized controlled trial

Abstract

Background: Preventing foot ulcers in people with diabetes can increase quality of life and reduce costs. Despite the availability of various interventions to prevent foot ulcers, recurrence rates remain high. We hypothesize that a multimodal treatment approach incorporating various footwear, self-management, and education interventions that matches an individual person's needs can reduce the risk of ulcer recurrence with beneficial cost-utility. The aim of this study is to assess the effect on foot ulcer recurrence, footwear adherence, and cost-utility of an integrated personalized assistive devices approach in high-risk people with diabetes.

Methods: In a parallel-group multicenter randomized controlled trial, 126 adult participants with diabetes mellitus type 1 or 2, loss of protective sensation based on the presence of peripheral neuropathy, a healed plantar foot ulcer in the preceding 4 years, and possession of any type of custom-made footwear will be included. Participants will be randomly assigned to either enhanced therapy or usual care. Enhanced therapy consists of usual care and additionally a personalized treatment approach including pressure-optimized custom-made footwear, pressure-optimized custom-made footwear for indoor use, at-home daily foot temperature monitoring, and structured education, which includes motivational interviewing and personalized feedback on adherence and self-care. Participants will be followed for 12 months. Assessments include barefoot and in-shoe plantar pressure measurements; questionnaires concerning quality of life, costs, disease, and self-care knowledge; physical activity and footwear use monitoring; and clinical monitoring for foot ulcer outcomes. The study is powered for 3 primary outcomes: foot ulcer recurrence, footwear adherence, and cost-utility, the primary clinical, patient-related, and health-economic outcome respectively.

Discussion: This is the first study to integrate multiple interventions for ulcer prevention into a personalized state-of-the-art treatment approach and assess their combined efficacy in a randomized controlled trial in people with diabetes at high ulcer risk. Proven effectiveness, usability, and cost-utility will facilitate implementation in healthcare, improve the quality of life of high-risk people with diabetes, and reduce treatment costs.

Trial registration: ClinicalTrials.gov NCT05236660. Registered on 11 February 2022.

Keywords: Adherence; Assistive devices; Cost–benefit analysis; Diabetic foot ulcer; Education; Footwear; Motivational interviewing; Personalized medicine; Prevention; Temperature monitoring.

Fig. 1

Schedule of intervention modalities. All follow-up visits can deviate a maximum 2.5 weeks from the scheduled timepoint. RAND, randomization visit; FU_x, follow-up visit (numbered by visit number); UV, unscheduled visit; FV, final visit

Fig. 2

Study design and main procedures for participants. All follow-up visits can deviate a maximum 2.5 weeks from the scheduled timepoint. * = An unscheduled visit becomes a scheduled visit when a participant develops an ulcer. This visit will be repeated every 3 months if an ulcer is not healed, which is the same frequency as normal follow-up visits. ‡ = Regular final visit will be at 12 months. However, if a participant has an ulcer at 12 months, there will be extra follow-up visits after the final visit. These will take place at 15 and 18 months or, if the ulcer has healed earlier, at 2 weeks after healing. The extra follow-ups follow the procedures of the unscheduled visit. ** = For enhanced therapy group only. † = the study questionnaire consists of a combination of multiple validated questionnaires, including adapted versions of the Monitor Orthopedic Footwear, treatment satisfaction questionnaire, COM-b (Capabilities, Opportunities, Motivations) questionnaire, and an assessment of knowledge about foot care based on the PIN questionnaire (Patients’ Interpretation of Neuropathy). ENROL, enrolment visit; BASE, baseline visit; RAND, randomization visit; FU_x, follow-up visit (numbered by visit number); UV, unscheduled visit; FV, final visit; SF-36, quality of life questionnaire; EQ-5D-5L, quality of life questionnaire measuring quality-adjusted life years; iMTA, Institute for Medical Technology Assessment questionnaires on medical consumption and productivity costs; CWIS, Cardiff Wound Impact Schedule questionnaire