OBJECTIVEPrescription custom-made footwear can only be effective in preventing diabetic foot ulcers if worn by the patient. Particularly, the high prevalence of recurrent foot ulcers focuses the attention on adherence, for which objective data are nonexisting. We objectively assessed adherence in patients with high risk of ulcer recurrence and evaluated what determines adherence.RESEARCH DESIGN AND METHODSIn 107 patients with diabetes, neuropathy, a recently healed plantar foot ulcer, and custom-made footwear, footwear use was measured during 7 consecutive days using a shoe-worn, temperature-based monitor. Daily step count was measured simultaneously using an ankle-worn activity monitor. Patients logged time away from home. Adherence was calculated as the percentage of steps that prescription footwear was worn. Determinants of adherence were evaluated in multivariate linear regression analysis.RESULTSMean ± SD adherence was 71 ± 25%. Adherence at home was 61 ± 32%, over 3,959 ± 2,594 steps, and away from home 87 ± 26%, over 2,604 ± 2,507 steps. In 35 patients with low adherence (<60%), adherence at home was 28 ± 24%. Lower BMI, more severe foot deformity, and more appealing footwear were significantly associated with higher adherence.CONCLUSIONSThe results show that adherence to wearing custom-made footwear is insufficient, particularly at home where patients exhibit their largest walking activity. This low adherence is a major threat for reulceration. These objective findings provide directions for improvement in adherence, which could include prescribing specific off-loading footwear for indoors, and they set a reference for future comparative research on footwear adherence in diabetes.

Footwear adherence at home increases 1 week after motivational interviewing to clinically relevant but not statistically significant levels (ie, 80%) but then returns over time to baseline levels. Away from home, adherence is already sufficient at baseline and remains so over time. The use of motivational interviewing seems feasible for the given purpose and patient group. These findings provide input to larger trials and provisionally suggest that additional or adjunctive therapy may be needed to better preserve adherence.

Offloading in custom-made footwear is often not sufficiently achieved in high-risk diabetic feet with deformity. Highest offloading success rates were seen at known high-risk locations such as previous ulcer locations and Charcot feet, the lowest success rates in forefoot deformities. Together with the large inter-subject variability in pressure outcomes, this emphasizes the need for evidence-based prescription and evaluation procedures to assure adequate offloading.