Results published in Diabetes Care demonstrate that the Podimetrics SmartMat detected as many as 97% of developing nontraumatic plantar foot ulcers on average five weeks before they presented clinically.
Importantly, 86% of patients used the mat at least three times per week and 88% of respondents reported it being easy-to-use, suggesting that patients readily accept this practical, new monitoring technology.
“The Podimetrics Remote Temperature Monitoring System could have huge benefits for patients with diabetes who are at high risk by significantly reducing morbidity and mortality associated with diabetic foot ulcers, which could also lead to improvements in resource utilization,” said Dr. Robert Frykberg, chief of the Podiatry Section in the Deptartment of Surgery at the Carl T Hayden Veterans Affairs Medical Center, professor at the University of Arizona College of Medicine (both Phoenix, USA) and lead investigator.
The study was a 34-week, multicentre evaluation of the Podimetrics Remote Temperature Monitoring System in 129 participants with diabetes and prior diabetic foot ulcers (DFU). The primary outcome of interest was development of nontraumatic plantar DFU, and the primary efficacy analysis was the accuracy of the Podimetrics SmartMat for predicting the occurrence of DFU over several temperature asymmetry thresholds.
Of the 129 participants who contributed evaluable data to the study, a total of 37 (28.7%) presented with 53 DFU (0.62 DFU/participant/year). At a temperature asymmetry threshold of 2.22°C, which is the standard threshold used in previous plantar thermometry studies, the system correctly identified 97% of observed DFU, with an average lead time of 37 days. Increasing the temperature threshold to 3.20°C decreased sensitivity to 70% but reduced the false-positive rate from 57% to 32% with approximately the same lead time of 35 days. Approximately 86% of the cohort used the system at least 3 days a week on average over the study.
“The false positive rate observed in this study was not surprising or concerning,” continues Frykberg. “This is particularly true given that the value of preventing a foot ulcer and its complications far outweighs the nuisance factor of a false alert. In a real-world setting, when a doctor gets a notification that a patient has a hotspot, the patient will be advised to reduce physical activity for a period to let the developing wound heal or may be asked to come in for a visit in serious cases. Even at the most sensitive setting presented in the study, these results translate to only 3.1 total notifications to the physician and patient per year, including all true and false positives.”