title: Evaluation of the Neuropad sudomotor function test as a screening tool for polyneuropathy in the elderly population with diabetes and pre-diabetes: the KORA F4 survey.
abstract: BACKGROUND
  Neuropad is a novel indicator test for sudomotor dysfunction, which has not been validated as a screening tool in a population-based study. This study aimed to evaluate the utility of Neuropad as a screening tool for distal symmetric polyneuropathy among elderly subjects with diabetes and pre-diabetes in the general population.
  
  
  METHODS
  Eligible subjects aged 61-82 years (n = 940) from the KORA F4 survey were examined, 201 of whom had diabetes and 231 had pre-diabetes (WHO 1999 criteria). Polyneuropathy was defined by the Michigan Neuropathy Screening Instrument (MNSI) score >3.
  
  
  RESULTS
  Polyneuropathy was diagnosed in 60 (29.9%) subjects with diabetes and in 45 (19.5%) subjects with pre-diabetes, respectively (p = 0.013). The sensitivity and negative predictive value of Neuropad (reading time: 10 min) for the diagnosis of polyneuropathy were moderately high, reaching 76.7% and 78.1% in subjects with diabetes and 57.8% and 76.5% in those with pre-diabetes, respectively. Conversely, the specificity and positive predictive value for the diagnosis of polyneuropathy were rather low: 35.5% and 33.6% in diabetic individuals and 33.3% and 17.3% in subjects with pre-diabetes, respectively. Use of the >2 cut-off and MNSI combined with monofilament examination did not improve the diagnostic performance of Neuropad.
  
  
  CONCLUSIONS
  In the elderly general population with diabetes and pre-diabetes, Neuropad has reasonable sensitivity but rather low specificity for the diagnosis of polyneuropathy. It is a useful simple and inexpensive tool to screen for and to exclude polyneuropathy as desired, while its low specificity implies that a longer reading time merits consideration.
authors.affiliation: Institute for Clinical Diabetology, German Diabetes Center at the Heinrich Heine University, Leibniz Center for Diabetes Research, Düsseldorf, Germany. dan.ziegler@ddz.uni-duesseldorf.de
authors.forename: D
authors.initials: D
authors.lastname: Ziegler
authors.forename: N
authors.initials: N
authors.lastname: Papanas
authors.forename: W
authors.initials: W
authors.lastname: Rathmann
authors.forename: M
authors.initials: M
authors.lastname: Heier
authors.forename: M
authors.initials: M
authors.lastname: Scheer
authors.forename: C
authors.initials: C
authors.lastname: Meisinger
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003929:Diabetic Neuropathies / Q000175:diagnosis*; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D011236:Prediabetic State / Q000150:complications* / Q000175:diagnosis; D011237:Predictive Value of Tests; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity
chemical_list: D011933:Reagent Kits, Diagnostic