A CROSS-SECTIONAL STUDY COMPARING 2 QUANTITATIVE SENSORY TESTING DEVICES IN INDIVIDUALS WITH DIABETES

OBJECTIVE - This study was designed to compare circumference discrimin ation thresholds, as assessed by the Tacticon (Tacticon, Inc., Westtow n, PA), a new quantitative sensory testing (QST) device, with vibrator y thresholds, an assessment modality of large sensory nerve fibers, in individuals with diabetes. RESEARCH DESIGN AND METHODS - In this stud y, 150 individuals with diabetes were evaluated. Vibratory thresholds and circumference discrimination thresholds, evaluated with the Tactic on, were determined using a two-alternative forced-choice procedure. R ESULTS - Vibratory thresholds increased with decreasing ability to dis criminate differences in circumference (P < 0.001) for those below and above 50 years of age. Agreement between the two QST devices was asse ssed via the K-statistic in both age-groups (i.e., less than or equal to 50 years old [kappa = 0.67], > 50 years old [kappa = 0.55]). In mul tiple logistic regression, where circumference discrimination threshol ds were the dependent variable, age, duration of diabetes, and height were found to be independently associated for those > 50 years old. CO NCLUSIONS - The Tacticon offers a simple method of assessing the compl ex function of area discrimination. Our results suggest that the Tacti con can detect neuropathy in the primary care setting. Its cost, porta bility, and ease of use provide some advantages over existing QST equi pment.