Standing balance and trunk position sense in impaired glucose tolerance (IGT)-related peripheral neuropathy

Type 2 diabetes mellitus (T2DM) and pre-diabetes or impaired glucose tolerance (IGT) affect a large segment of the population. Peripheral neuropathy (PN) is a common complication of T2DM, leading to sensory and motor deficits. While T2DM-related PN often results in balance- and mobility-related dysfunction which manifests as gait instability and falls, little is known about balance capabilities in patients who have evidence of PN related to IGT (IGT–PN). We evaluated patients with IGT–PN on commonly-used clinical balance and mobility tests as well as a new test of trunk position sense and balance impairment, trunk repositioning errors (TREs). Eight participants aged 50–72 years with IGT–PN, and eight age- and gender-matched controls underwent balance, mobility and trunk repositioning accuracy tests at a university neurology clinic and mobility research laboratory. Compared to controls, IGT–PN participants had as much as twice the magnitude of TREs and stood approximately half as long on the single leg balance test. People with IGT–PN exhibit deficits in standing balance and trunk position sense. Furthermore, there was a significant association between performance on commonly-used clinical balance and mobility tests, and electrophysiological and clinical measures of neuropathy in IGT–PN participants. Because IGT-related neuropathy represents the earliest stage of diabetic neuropathy, deficits in IGT–PN participants highlight the importance of early screening in the dysglycemic process for neuropathy and associated balance deficits.