Autor:innen:
Dr. med. Gidon J. Bönhof | Deutsches Diabetes-Zentrum (DDZ), Leibniz-Zentrum für Diabetes-Forschung an der Heinrich-Heine-Universität Düsseldorf | Germany
Dr. Alexander Strom | Deutsches Diabetes-Zentrum, Leibniz-Zentrum für Diabetes-Forschung an der Heinrich-Heine-Universität Düsseldorf | Germany
Prof. Dr. Nikolaos Papanas | Diabetes Center, Diabetic Foot Clinic, Democritus University of Thrace | Greece
Prof. Dr. Rayaz A. Malik | Weill Cornell Medicine-Qatar | Qatar
Prof. Dr. Julia Szendrödi | Deutsches Diabetes-Zentrum, Leibniz-Zentrum für Diabetes-Forschung an der Heinrich-Heine-Universität Düsseldorf | Germany
Prof. Dr. Karsten Müssig | Deutsches Diabetes-Zentrum, Leibniz-Zentrum für Diabetes-Forschung an der Heinrich-Heine-Universität Düsseldorf | Germany
Prof. Dr. Michael Roden | Deutsches Diabetes-Zentrum, Leibniz-Zentrum für Diabetes-Forschung an der Heinrich-Heine-Universität Düsseldorf | Germany
Prof. Dr. Dan Ziegler | Deutsches Diabetes-Zentrum, Leibniz-Zentrum für Diabetes-Forschung an der Heinrich-Heine-Universität Düsseldorf | Germany
Aims: The relative performance of sudomotor function tests in detecting diabetic sensorimotor polyneuropathy (DSPN) has not yet been compared. The benefit from quantitative Neuropad analysis needs to be evaluated.
Methods: Sudomotor function was assessed at the sole of the foot of individuals with T1D (diabetes duration (DD) [n]: ≤1 year [n=55], 5 years [n=55], and T2D (≤1 year [n=84], 5 years [n=100], 10 years [n=27]) and NGT [n=78] and with painless (-p) and painful DSPN (+p) (n=149/148, DD [mean±SD]: 16.7±13.1/16.6±11.6 years) using Sudoscan (electrochemical skin conductance (ESC)) and Neuropad, quantified with Sudometrics software. Intraepidermal nerve fiber density (IENFD) was determined in 189 individuals. Sudomotor dysfunction was defined at values (Neuropad-Sudometrics/Sudoscan) below the age-dependent 5th percentile of controls.
Results: The percentages of individuals with sudomotor dysfunction according to Neuropad-Sudometrics and Sudoscan were similar within the groups: controls: 3.8 vs 3.8%, T1D≤1yr: 3.6 vs 1.8%, T1D-5yr: 5.5 vs 5.5%, T2D≤1yr: 10.7 vs 4.8%, T2D-5yr: 12.0 vs 10.0%, T2D-10yr: 18.5 vs 18.5%, DSPN-p: 28.9 vs 27.5%, and DSPN+p: 29.7 vs 33.1%. ESC was lower in DSPN+p vs -p (63±20 vs 58±21 µS; P=0.016). Neuropad-Sudometrics correlated with ESC in DSPN (r=0.422; P≤0.001). Both tests were associated with IENFD (Neuropad-Sudometrics/ESC: β=0.331/0.293; P≤0.01). Sensitivity and specificity for Neuropad-Sudometrics vs ESC were 37% vs 41% and 87% vs 90%.
Conclusions: Sudoscan detected slightly greater sudomotor dysfunction than Neuropad-Sudometrics in painful vs painless DSPN at overall similar diagnostic performance. Both tests were highly specific for the diagnosis of small-fiber neuropathy. Sudomotor function was largely preserved in recent-onset diabetes.