Feasibility and Efficacy of a Smart Mat Technology to Predict Development of Diabetic Plantar Ulcers
Article Figures & Tables
Figures
- Figure 1
The study device was an in-home, wireless, thermometric mat designed for remote temperature monitoring of patients at risk for inflammatory foot diseases.
- Figure 2
Comparison of thermometric data from a participant who did not develop a new DFU during the study (left) with the data from a participant who did (right). In the thermograms, the plantar aspect of the foot is viewed from below so that the right foot is at image left.
- Figure 3
Participant adherence to daily use of study device using an ITT (A and B) and a per-protocol (C and D) approach.
Tables
- Table 1
Cohort demographic characteristics and comparison of participants who developed a new DFU during the study and those who did not
All participants No DFU during study DFU during study Number of DFU 53 0 53 Number of participants 129 92 37 Age (years) 61.8 ± 10.5 62.2 ± 11.0 61.0 ± 9.3 Male 86.0% (111/129) 87.0% (80/92) 83.8% (31/37) Height (m) 1.78 ± 0.1 1.77 ± 0.11 1.79 ± 0.08 Weight (kg) 105.9 ± 23.7 103.1 ± 23.9 111.7 ± 22.2 BMI (kg/m2) 33.4 ± 6.6 32.7 ± 6.9 34.8 ± 5.9 History of smoking 42.6% (52/122) 44.2% (38/86) 38.9% (14/36) History of alcohol use 41.9% (39/93) 42.6% (29/68) 40.0% (10/25) Performs regular exercise 35.2% (45/128) 35.2% (32/91) 35.1% (13/37) Living conditions Alone 35.9% (46/128) 38.0% (35/92) 30.6% (11/36) With others 64.1% (82/128) 62.0% (57/92) 69.4% (25/36) Ambulatory status Active without assistance 79.1% (102/129) 78.3% (72/92) 81.1% (30/37) Active with assistance 17.8% (23/129) 17.4% (16/92) 18.9% (7/37) Inactive 3.1% (4/129) 4.3% (4/92) 0.0% (0/37) Years since diabetes diagnosed 17.6 ± 10.8 16.9 ± 10.9 19.1 ± 10.7 Insulin-dependent 60.5% (78/129) 55.4% (51/92) 73.0% (27/37) Hemoglobin A1c DCCT-derived (%) 8.3 ± 2.0 8.2 ± 2.1 8.6 ± 1.8 IFCC-recommended (mmol/mol) 67 ± 22 66 ± 23 70 ± 20 History of amputation 55.7% (59/106) 55.3% (42/76) 56.7% (17/30) History of Charcot arthropathy 6.6% (8/122) 5.7% (5/87) 8.6% (3/35) Months since last DFU healed 13.9 ± 39.2 16.1 ± 45.1 8.2 ± 14.4 DFU history History of hallux DFU 34.9% (45/129) 31.5% (29/92) 43.2% (16/37) History of minor toe DFU 55.8% (72/129) 52.2% (48/92) 64.9% (24/37) History of metatarsal DFU 41.9% (54/129) 40.2% (37/92) 45.9% (17/37) History of midfoot or heel DFU 4.7% (6/129) 3.3% (3/92) 8.1% (3/37) Vascular status Left ankle-brachial index 1.14 ± 0.18 1.14 ± 0.16 1.17 ± 0.21 Right ankle-brachial index 1.18 ± 0.28 1.20 ± 0.31 1.15 ± 0.19 Peripheral vascular disease 9.9% (12/121) 11.5% (10/87) 5.9% (2/34) History of vascular surgery 15.6% (20/128) 15.4% (14/91) 16.2% (6/37) Neurological status Detects left 10-g monofilament 17.9% (21/117) 19.8% (16/81) 13.9% (5/36) Detects right 10-g monofilament 17.2% (20/116) 18.8% (15/80) 13.9% (5/36) Wears therapeutic shoes 86.3% (107/124) 86.5% (77/89) 85.7% (30/35) VHA participant 45.0% (58/129) 46.7% (43/92) 40.5% (15/37) Study adherence (uses/week) 5.5 ± 1.2 5.4 ± 1.3 5.6 ± 1.1 Temperature asymmetry (°C)** 3.10 ± 1.57 2.81 ± 1.42 3.94 ± 1.68 Data are means ± SD or percentage (n/N).
DCCT, Diabetes Control and Complications Trial; IFCC, International Federation of Clinical Chemistry; VHA, Veterans Health Administration.
↵**P < 0.01.
- Table 2
Summary of DFU prediction for four foot temperature asymmetry thresholds
Asymmetry threshold 2.22°C 2.75°C 3.20°C 3.75°C Sensitivity (%) 97 90 70 50 Specificity (%) 43 57 68 81 Alert frequency (per participant/year) 3.1 2.2 1.7 1.1 Alert lead time (days) 37 ± 18 36 ± 17 35 ± 16 35 ± 17 Positive predictive value (%) 16.6 19.7 20.4 23.6 Negative predictive value (%) 99.2 98.0 95.1 92.3 Data are means ± SD unless otherwise indicated.
In this Issue
