Duration of Type 2 Diabetes is a Predictor of Elevated Plantar Foot Pressure

Elevated plantar pressure is considered a significant risk factor for ulceration in diabetes mellitus. The aim of this study was to determine whether duration of diabetes could affect plantar pressure in patients with no known significant comorbidity or foot pathology.

Participants with type 2 diabetes, but without known confounding factors that could alter peak pressure, were matched for age, weight, and gender and categorized into 3 groups of diabetes duration: group 1 (1-5 yr), group 2 (6-10 yr), and group 3 (11-15 yr). Plantar pressures were recorded utilizing a two-step protocol at a self-selected speed.

One-way analysis of variance (ANOVA) revealed significant differences in mean peak plantar pressures between the three groups under the 2^nd - 4^th metatarsophalangeal joint (MPJ) region of interest (ROI) (p = 0.012 and p = 0.022, respectively) and left heel (p = 0.049). Also, a significant difference in mean pressure-time integral under the left 2^nd - 4^th MPJ ROI (p = 0.021) and right heel (p = 0.048) was observed. Regression analysis confirmed that mean peak plantar pressures in the first group (but not in the second group) were significantly lower than in the third group (p = 0.005).

As the duration of diabetes increased, peak plantar pressure increased significantly under the 2^nd - 4^th MPJ ROIs. These findings suggest that clinicians should make more use of pressure mapping technology as part of their clinical management plan in patients with diabetes >10 yr, even if they have no complications or deformities, to preserve functional limbs in this high-risk population.