title: Continuous subcutaneous insulin infusion preserves axonal function in type 1 diabetes mellitus.
abstract: BACKGROUND
  Diabetic peripheral neuropathy is a common and debilitating complication of diabetes mellitus. Although strict glycaemic control may reduce the risk of developing diabetic peripheral neuropathy, the neurological benefits of different insulin regimens remain relatively unknown.
  
  
  METHODS
  In the present study, 55 consecutive patients with type 1 diabetes mellitus underwent clinical neurological assessment. Subsequently, 41 non-neuropathic patients, 24 of whom were receiving multiple daily insulin injections (MDII) and 17 receiving continuous subcutaneous insulin infusion (CSII), underwent nerve excitability testing, a technique that assesses axonal ion channel function and membrane potential in human nerves. Treatment groups were matched for glycaemic control, body mass index, disease duration and gender. Neurophysiological parameters were compared between treatment groups and those taken from age and sex-matched normal controls.
  
  
  RESULTS
  Prominent differences in axonal function were noted between MDII-treated and CSII-treated patients. Specifically, MDII patients manifested prominent abnormalities when compared with normal controls in threshold electrotonus (TE) parameters including depolarizing TE(10-20ms), undershoot and hyperpolarizing TE (90-100 ms) (P < 0.05). Additionally, recovery cycle parameters superexcitability and subexcitability were also abnormal (P < 0.05). In contrast, axonal function in CSII-treated patients was within normal limits when compared with age-matched controls. The differences between the groups were noted in cross-sectional analysis and remained at longitudinal follow-up.
  
  
  CONCLUSIONS
  Axonal function in type 1 diabetes is maintained within normal limits in patients treated with continuous subcutaneous insulin infusion and not with multiple daily insulin injections. This raises the possibility that CSII therapy may have neuroprotective potential in patients with type 1 diabetes.
authors: Translational Neuroscience Facility, School of Medical Sciences, University of New South Wales, Sydney, Australia.
authors: Natalie
authors: N
authors: Kwai
authors: Ria
authors: R
authors: Arnold
authors: Ann M
authors: AM
authors: Poynten
authors: Cindy S-Y
authors: CS
authors: Lin
authors: Matthew C
authors: MC
authors: Kiernan
authors: Arun V
authors: AV
authors: Krishnan
mesh_terms: D000328:Adult; D001369:Axons / Q000187:drug effects* / Q000378:metabolism; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D003929:Diabetic Neuropathies / Q000517:prevention & control*; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D055104:Infusions, Subcutaneous; D007328:Insulin / Q000008:administration & dosage* / Q000627:therapeutic use; D007332:Insulin Infusion Systems; D061386:Insulin, Regular, Human / Q000008:administration & dosage; D008137:Longitudinal Studies; D008297:Male; D009460:Neurologic Examination; D018696:Neuroprotective Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D009517:New South Wales; D017933:Peripheral Nervous System / Q000187:drug effects / Q000503:physiopathology
chemical_list: D007004:Hypoglycemic Agents; D007328:Insulin; D061386:Insulin, Regular, Human; D018696:Neuroprotective Agents
keywords: CSII; MDI; insulin; neuropathy; neuroprotective; type 1 diabetes mellitus