Table 2 Comparison of intraepidermal nerve fiber (IENF) densities and nerve conduction studies

MeasureIGTDiabetesp Value
Values are median, mean ± SD.
* Epidermal nerve fiber density at distal leg in patients with diabetes and those with IGT are significantly lower than normal values (p < 0.01).
† Epidermal nerve fiber density at proximal thigh in patients with diabetes (p = 0.22) and those with IGT (p = 0.12) is not significantly lower than the normal values.
IGT = impaired glucose tolerance.
Skin biopsy, IENF/mm
    Distal leg (normative range 13.8 ± 6.714)0.8, 3.9 ± 6.1*0.2, 0.3 ± 0.2*0.01
    Distal thigh9.2, 10.5 ± 7.910.1, 9.6 ± 6.30.97
    Proximal thigh (normative range 21.1 ± 10.414)14.8, 16.1 ± 5.014.9, 14.9 ± 7.30.63
Electrophysiology
    Sural nerve amplitude, μV (normal >9 μV for age < 60 y, >5 μV for age > 60 y)9.1, 10.3 ± 9.53.3, 7.3 ± 13.60.056
    Sural nerve conduction velocity, m/s (normal >39 m/s)45.8, 46.2 ± 5.938.8, 39.8 ± 4.20.03
    Deep peroneal amplitude, μV (normal >2 mV)2.6, 3.0 ± 3.21.7, 2.2 ± 1.80.28