Nanosilver Dressings and 12-Week Healing in Diabetic Foot Ulcers: A Retrospective Propensity Score-Matched Study

Summary

This retrospective propensity score-matched study evaluates the association of nanosilver versus alginate dressing strategies with 12-week wound healing and related clinical outcomes in multidisciplinary diabetic-foot care.

Abstract

Diabetic foot ulcers (DFUs) are associated with prolonged morbidity and limb-related complications. This single-center retrospective cohort study compared nanosilver and alginate primary dressing strategies in patients managed within a multidisciplinary diabetic-foot program between January 2020 and December 2023. Among 393 screened patients, 361 formed the unmatched cohort, including 121 treated with nanosilver and 240 with alginate dressings; 1:1 propensity-score matching generated 115 matched pairs. The single primary endpoint was complete wound healing at week 12. Healing occurred in 87 of 115 patients (75.7%) receiving nanosilver and 65 of 115 (56.5%) receiving alginate dressings (matched OR, 2.47; 95% CI, 1.32–4.84; P = 0.003; matched RR, 1.34; 95% CI, 1.11–1.62). At least 50% wound-area reduction at week 4 occurred in 82.6% versus 67.0% (matched OR, 2.80; 95% CI, 1.32–6.46; Holm-adjusted P = 0.015), and median time to complete healing was 45 versus 58 days (HR, 1.58; 95% CI, 1.22–2.05; Holm-adjusted P < 0.004). The primary association remained similar in the extended measured-confounding sensitivity analysis (adjusted OR, 2.31; 95% CI, 1.17–4.56). Other clinical and safety outcomes were exploratory. Nanosilver dressing use was associated with greater 12-week complete healing and shorter time to closure in this matched tertiary-care cohort; prospective multicenter validation is required.

Introduction

Diabetic foot ulcers (DFUs) are a major complication of diabetes and are associated with prolonged morbidity, infection, hospitalization, lower-extremity amputation, and substantial healthcare burden¹. Despite advances in multidisciplinary care, a substantial proportion of ulcers remain unhealed at 12 weeks, and recurrence after wound closure is common^2,3. Even with progress in multidisciplinary care, as many as one-third of DFUs remain unhealed in 12 weeks, and over 40% recur in the first year. DFU is also associated with substantial systemic morbidity, and major lower-extremity amputa....

Protocol

The study was conducted in accordance with the Declaration of Helsinki and reported in accordance with the STROBE recommendations for observational studies. The Ethics Committee of the General Hospital of Northern Theater Command granted ethical approval (approval number NCH202508221). Because of the retrospective design and use of deidentified clinical data, the Ethics Committee waived the requirement for written informed consent. Only deidentified analytic data were used for the study analyses.

Study design and setting

This retrospective cohort study was conducted at the General Hospital of Nor....

Results

Patient characteristics

Between January 2020 and December 2023, 393 patients with diabetic foot ulcers (DFUs) were screened for eligibility, and cohort assembly is shown in Figure 1. Thirty-two patients were excluded before formation of the unmatched cohort: 8 had a non-diabetic or non-index ulcer, 4 lacked baseline variables required for the primary propensity-score model, 3 had insufficient follow-up to ascertain the week-12 primary endpoint, 6 .......

Discussion

The principal finding of this real-world retrospective propensity score–matched study was that nanosilver dressing use was associated with a higher proportion of complete wound healing at week 12 than alginate dressing use. The primary matched estimate was supported by the extended measured-confounding and WIfI-complete sensitivity analyses. Among the key secondary healing outcomes, complete healing at week 8, at least 50% wound-area reduction at week 4, and time to complete healing remained supportive after Holm a.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
0.9% Sodium Chloride Injection	Sichuan Kelun Pharmaceutical Co., Ltd.	N/A	Used for wound cleansing and routine clinical care
3M Scotchcast Plus Casting Tape	3M Health Care	82003	Fiberglass casting tape used for total-contact casting when clinically indicated
Accu-Chek Inform II Blood Glucose Monitoring System	Roche Diagnostics	Accu-Chek Inform II	Used for routine glucose monitoring during diabetic-foot care
ACTICOAT FLEX 3 Antimicrobial Barrier Dressing	Smith+Nephew	66800396	Nanocrystalline silver antimicrobial dressing used as the primary nanosilver dressing; changed every 48–72 h according to exudate and wound-bed condition
Agilent 7900 ICP-MS	Agilent Technologies	7900 ICP-MS	Used for serum silver ion measurement when clinically indicated
BD BBL CultureSwab	BD	220099	Used for microbiological sampling when clinically indicated
Canon EOS 80D digital camera	Canon Inc.	EOS 80D	Used for standardized serial wound photography
DARCO OrthoWedge Forefoot Offloading Shoe	DARCO International	OrthoWedge	Used for forefoot pressure redistribution and offloading when clinically indicated
Disposable surgical blade, No. 15	Kai Industries Co., Ltd.	B15	Used during sharp wound debridement
Disposable wound measuring ruler	Jiangsu Kangjin Medical Instrument Co., Ltd.	N/A	Used as a calibration reference for wound-size measurement in photographs
Handheld vascular Doppler system	Huntleigh Healthcare	Dopplex DMX	Used for ankle–brachial index and peripheral perfusion assessment
ImageJ software	National Institutes of Health	Version 1.53t	Used for calibrated digital planimetry and wound-area measurement
IWGDF/IDSA infection criteria	International Working Group on the Diabetic Foot/Infectious Diseases Society of America	2023 guideline	Used to define diabetic foot infection and reinfection
KALTOSTAT Calcium Sodium Alginate Dressing	ConvaTec	168212	Calcium sodium alginate primary dressing used as the comparator after standardized wound-bed preparation
MatchIt package	R package	Version 4.5.5	Used for 1:1 nearest-neighbor propensity-score matching
Neusoft Hospital Information System / Electronic Medical Record platform	Neusoft Medical Systems	N/A	Institutional HIS/EMR deployment; Used for retrospective extraction of clinical and outcome data
R software	R Foundation for Statistical Computing	Version 4.3.2	Used for statistical analyses, propensity-score matching, and time-to-event analyses
Resona 7 Diagnostic Ultrasound System	Mindray	Resona 7	Used for Doppler ultrasonography of lower-limb perfusion
Roche cobas c 702 Automated Chemistry Analyzer	Roche Diagnostics	cobas c 702	Used for serum creatinine, lipid profile, and routine biochemical tests
Sterile gauze and absorbent pads	Winner Medical Co., Ltd.	N/A	Used for routine wound cleaning and dressing support
Sterile surgical debridement kit	Jinhuan Medical Products Co., Ltd.	JH-SDK-01	Used for sharp debridement of necrotic tissue and callus
survival package	R package	Version 3.5	Used for Kaplan–Meier and Cox proportional hazards analyses
Sysmex XN-1000 Automated Hematology Analyzer	Sysmex Corporation	XN-1000	Used for routine blood-count assessment
Tosoh HLC-723G8 HbA1c Analyzer	Tosoh Corporation	HLC-723G8	Used for baseline glycated hemoglobin measurement
VITEK 2 Compact	bioMérieux	VITEK 2 Compact	Used for culture-based pathogen identification and antimicrobial susceptibility testing
Wagner ulcer classification	Not applicable	Not applicable	Clinical grading system used to characterize diabetic foot ulcer depth and tissue involvement