Further studies on the electrodiagnosis of diabetic peripheral polyneuropathy using discriminant function analysis

Discriminant function analysis can be useful when applied to multiple nerve conduction parameters for diabetic and nondiabetic subjects to reveal the essential dimension along which key neuropathic differences occur between these groups. In this study, 19 electrophysiologic parameters were used in a stepwise discriminant function analysis to reveal a highly significant dimension of intergroup differences between 67 diabetic and 75 normal adult Japanese-American males. The classification functions thereby derived are more sensitive and specific than those reported previously for this population. Furthermore, when 72 additional subjects with impaired glucose tolerance were examined, they showed considerable overlap with the normal and separation from the diabetic groups, respectively. Their intermediate position between normal and diabetics in the key discriminant dimension indicates that essential neuropathic change is, at most, incipient in this latter group.