title: Sural sensory action potential identifies diabetic peripheral neuropathy responders to therapy.
abstract: Identifying patients with diabetic peripheral neuropathy (DPN) amenable to therapy is a challenge. To determine whether the amplitude of the sural sensory nerve action potential (sural SNAP) reflects the severity of DPN, an analysis was performed on 205 patients with DPN, identified by an abnormal vibration detection threshold (VDT), who were enrolled in a multinational clinical trial investigating ruboxistaurin (RBX) mesylate. Nerve conduction velocity and response amplitude and latency were measured and compared. VDT was significantly lower in those with preserved sural SNAPs (n = 128) than in those in whom they were absent (n = 77; 21.5 vs. 22.7 JND units, P = 0.002). Thus, preserved sural SNAP denoted less severe DPN. Logistic regression analyses evaluating baseline characteristics, HbA(1c), and baseline symptom scores identified only DPN duration as a factor that might contribute to the presence of sural SNAP (P = 0.004; OR = 0.896). For patients with abnormal VDT, preserved sural SNAP identifies a patient population with less severe DPN who may respond to therapeutic intervention in clinical trials.
authors.affiliation: Strelitz Diabetes Institutes, Eastern Virginia Medical School, Norfolk, 23510, USA. vinikal@evms.edu
authors.forename: Aaron I
authors.initials: AI
authors.lastname: Vinik
authors.forename: Vera
authors.initials: V
authors.lastname: Bril
authors.forename: William J
authors.initials: WJ
authors.lastname: Litchy
authors.forename: Karen L
authors.initials: KL
authors.lastname: Price
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Bastyr
mesh_terms: D000200:Action Potentials; D000328:Adult; D003929:Diabetic Neuropathies / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology*; D004311:Double-Blind Method; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007211:Indoles / Q000627:therapeutic use; D016015:Logistic Models; D008297:Male; D008301:Maleimides / Q000627:therapeutic use; D008875:Middle Aged; D009431:Neural Conduction; D011237:Predictive Value of Tests; D012684:Sensory Thresholds; D012720:Severity of Illness Index; D013497:Sural Nerve / Q000503:physiopathology*; D014732:Vibration
chemical_list: D004791:Enzyme Inhibitors; D007211:Indoles; D008301:Maleimides; C099154:ruboxistaurin