Objective We studied whether sensory function abnormalities are present at diagnosis and whether they develop in the early stages of non-insulin-dependent diabetes (NIDDM).

Research Design and Methods Quantitative assessments of vibration sensitivity at the hallux and index fingers, and thermal sensitivity at the hallux were performed at screening (2-h oral glucose tolerance tests) for diabetes in 364 individuals. Twenty-five subjects diagnosed with NIDDM and 25 matched nondiabetic subjects were restudied after an interval of 12–41 mo.

Results When those with NIDDM (n = 41) or impaired glucose tolerance (IGT) (n = 38) were compared with nondiabetic subjects, there were no significant differences in sensory function indices. However, the vibration threshold and HbA_1c were related among those found to be hyperglycemic (IGT and NIDDM combined P < 0.05; NIDDM alone P < 0.05). Among diabetic subjects, the vibration threshold and interaction term of height and Hba_1c were positively related in a multiple regression analysis (P < 0.01). There were increments in all sensory thresholds in diabetic patients at follow-up (P < 0.05 for all). Increments were smaller in control subjects.

Conclusions These data suggest that although sensory function tends to be normal at diagnosis in NIDDM patients, there appears to be a diminution in sensory function as the disease progresses. An interaction between metabolic factors and height may influence sensory function early in the course of NIDDM.