Sensory thresholds in older adults: reproducibility and reference values

To evaluate the test-retest reproducibility of vibratory perception (VPT) and thermal discrimination (TDT) thresholds on the foot in older adults, we examined 20 50-76-year-old subjects with, and 19 without non-insulin-dependent diabetes mellitus. Adjusted reference values for both thresholds were obtained by assessing the relations with age, body height, and sex among 216 subjects with normal glucose tolerance, of the same age, sampled randomly from a geographically defined general population. The VPT appeared to be more reproducible than the TDT (reliability coefficient 0.89 vs. 0.54). The reproducibility of the VPT was inversely related to age and better for men than for women. Diabetes and glycemic level did not affect the reproducibility of either threshold. Both thresholds were related to age and height. Women had a higher VPT than men. The relations between sex and sensory thresholds at the lower limb, reported in previous studies, were probably confounded by height.