title: Does vitamin D have any role in the improvement of diabetic peripheral neuropathy in type 1 diabetic patients?
abstract: OBJECTIVE
  The aim of this study was to evaluate the relationship between diabetic peripheral neuropathy (DPN) and vitamin D, nerve growth factor (NGF) and oxidative stress markers in patients with type 1 diabetes.
  
  
  METHODS
  Ninety-six patients with type 1 diabetes were included in the study. All patients were evaluated for DPN with Michigan Neuropathy Screening Instrument. Fasting blood glucose, HbA1c, lipid parameters, 25 (OH) D3, NGF, total oxidant status, total antioxidant status and oxidative stress index were measured.
  
  
  RESULTS
  Twenty-six patients (27 %) had DPN (group 1) and 70 patients did not have neuropathy (group 2). When the groups were evaluated with respect to general demographic characteristics, no differences were detected. Mean age, duration of diabetes and retinopathy were found significantly higher in patients who had neuropathy. Glomerular filtration rate levels were significantly lower in the neuropathy group. Between the groups, 25 (OH) vitamin D levels were significantly lower in the neuropathy group, while there were no differences in NGF levels or in oxidative stress markers. Michigan neuropathy examination score was positively correlated with age, and diabetes duration was negatively correlated with 25 (OH) vitamin D levels. In addition, 25 (OH) vitamin D was positively correlated with NGF. In the logistic regression analysis to determine the independent variables that will affect the development of neuropathy, duration of diabetes was detected as the only factor (p = 0.039, OR = 1.071).
  
  
  CONCLUSIONS
  It seems that the most important risk factor for the development of neuropathy in type 1 diabetic patients is disease duration.
authors.affiliation: Department of Internal Medicine, Endocrinology and Metabolism, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey. uozoguz@yahoo.com.tr.
authors.forename: U
authors.initials: U
authors.lastname: Ozuguz
authors.affiliation: Department of Neurology, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey.
authors.forename: S
authors.initials: S
authors.lastname: Oruc
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey.
authors.forename: M S
authors.initials: MS
authors.lastname: Ulu
authors.affiliation: Department of Neurology, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey.
authors.forename: H
authors.initials: H
authors.lastname: Demirbas
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Acay
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey.
authors.forename: B
authors.initials: B
authors.lastname: Coker
authors.affiliation: Department of Neurology, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey.
authors.forename: B
authors.initials: B
authors.lastname: Beyazıt
authors.affiliation: Department of Neurology, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey.
authors.forename: M
authors.initials: M
authors.lastname: Yaman
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey.
authors.forename: T
authors.initials: T
authors.lastname: Koken
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000150:complications*; D003929:Diabetic Neuropathies / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D012307:Risk Factors; D014807:Vitamin D / Q000097:blood / Q000494:pharmacology*
chemical_list: D015415:Biomarkers; D014807:Vitamin D
keywords: Nerve growth factor; Neuropathy; Oxidative stress; Type 1 diabetes; Vitamin D