Selected Function Performance in Healthy Young and Old, as well as People with Peripheral Neuropathy

Abstract

Peripheral Neuropathy (PN) is characterized by altered cutaneous sensitivity. While individuals with PN present with an increased risk of falls, little is known about its effects on common measures of physical function. The PURPOSE of this study was to compare performance in selected physical function in people with PN, healthy agematched controls (HO) and young adults (HY). METHODS: Thirteen people with diagnosed PN (11 women, 2 men, mean age = 66.1 ± 25.1 years; height = 167.7 ± 16.4 cm, body mass = 69.9 ± 16.6 kg), 13 HO (8 women, 5 men, mean age = 60.3 ± 6.7 years; height =173.2 ± 20.8 cm, body mass = 78.0 ± 33.6 kg), and 13 HY (10 women, 3 men, mean age = 21.4 ± 1.6 years; height =168.5 ± 14.4 cm, body mass = 65.7 ± 44.6 kg) signed a consent form approved by the IRB. Eyes-closed standing balance was evaluated by the average velocity (VEL, cm/s) and the area enclosing 95% (A95, cm2) of the body center of pressure. Knee strength (Nm) was assessed by maximum isokinetic (60 deg/s) knee extensor (KE) and flexor peak torque (KF). Functional capacity and mobility were measured by the six minute walk (6MW, m) test and the timed up-and-go (TUG, sec) test, respectively. Sensation of 5 foot sole locations was evaluated with a 5.07 gauge monofilament. ANOVA was used for comparison. RESULTS: The PN exhibited severe loss of sensitivity in the five tested sites as compared to the HO and HY (PN = 3.4 ± 3.4, HO = 4.9 ± .9, HY = 5 ± 0 sites, p < .001). The PN walked significantly less distance in the 6MW compared to the HO and HY (PN = 485 ± 114, HO = 586 ± 107, HY = 604 ± 72, p < .001). PN took significantly longer in completing TUG tests (PN = 8.1 ± .6, HO = 6.0 ± .2, HY = 5.2 ± .2). A95 and VEL measurements demonstrated that the PN (10.8 ± 3.1, 3.2 ± .4) was different (P < .02, P < .003) from the HY (3.1 ± .9, 1.4 ± .1). No difference was observed between the HO (4.4 ± .8, 2.3 ± .4) and the other groups. KE was significantly lower in the PN compared to the HY, yet no difference was observed between the HO and the other groups (PN = 97 ± 21, HO = 127 ± 21, HY = 153 ± 22, p < .04). No significant group differences were observed in KF. CONCLUSIONS: Minimal difference was observed between the performance of HY and HO, suggesting that normal aging has little effect on the tested physical function. PN is a debilitating movement disorder that has substantial effects on weight-bearing measures of physical function.