title: Assessment of diabetic polyneuropathy and autonomic neuropathy using current perception threshold in korean patients with diabetes mellitus.
abstract: BACKGROUND
  The current perception threshold (CPT) could be quantified by stimulating Aβ and C fibers at 2,000 and 5 Hz, respectively. C fibers play a role in the autonomic nervous system and are involved in temperature and pain sensation. We evaluated the usefulness of CPT for diagnosing distal polyneuropathy (DPN) and cardiovascular autonomic neuropathy (CAN) in diabetic patients.
  
  
  METHODS
  The CPT was measured in the index finger (C7 level) and in the third toe (L5 level) in diabetic patients aged 30 to 69 years. We assessed DPN according to the neuropathy total symptom score-6 (NTSS-6) and 10-g monofilament pressure sensation. Subjects with a NTSS-6 >6 or with abnormal 10-g monofilament sensation were defined to have DPN. CAN was evaluated by spectral analysis of heart rate variability and by Ewing's traditional tests.
  
  
  RESULTS
  The subjects with DPN had significantly higher CPT at all of the frequencies than the subjects without DPN (P<0.05). Abnormal 10-g monofilament sensation and NTSS-6 >6 could be most precisely predicted by CPT at 2,000 and 5 Hz, respectively. However, only 6.5% and 19.6% of subjects with DPN had an abnormal CPT at 2,000 Hz at the C7 and L5 levels. Although CPT at 5 Hz showed a negative correlation with the power of low and high frequency in the spectral analysis (P<0.05), only 16.7% of subjects with CAN exhibited an abnormal CPT at the same frequency.
  
  
  CONCLUSIONS
  Although the CPT is significantly associated with neuropathic symptoms or signs corresponding to the nerve fiber stimulated, it provides little additional information compared with conventional evaluations.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea. ; Department of Internal Medicine, Boramae Medical Center, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Bo Kyung
authors.initials: BK
authors.lastname: Koo
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea. ; Department of Internal Medicine, Hallym University College of Medicine, Chuncheon, Korea.
authors.forename: Jung Hun
authors.initials: JH
authors.lastname: Ohn
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Soo-Heon
authors.initials: SH
authors.lastname: Kwak
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea. ; Department of Internal Medicine, Boramae Medical Center, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Min Kyong
authors.initials: MK
authors.lastname: Moon
keywords: Cardiac autonomic neuropathy; Current perception threshold; Diabetic neuropathy